NetWare 386 System Messages: Disk, Memory and Accounting

Glenn Westin 
Consultant 
Systems Engineering Division

Abstract:  
This AppNote provides explanations and solutions for operating system 
messages appearing on the NetWare 386 server console. Organization is 
alphabetical with additional notation concerning each message's source 
process and level of severity.

Introduction

This document is the first in a series of AppNotes designed to provide an 
explanation of, and solution to, the many operating system messages that may 
appear at the NetWare 386  server console.

The NetWare 386 operating system contains approximately 1,000 messages. These
messages inform the administrator of the status of the operating system. Some
of the messages are initiated by errors, while others provide information.

The messages referenced in this AppNote have been organized according to 
functionality and severity. 

Functionality

NetWare functionality falls into twelve main categories, each with a varying 
amount of related messages. The categories are as follows:

Accounting and statistics

Ascychronous Event Scheduler (AES) and Timer

Bindery

Communications

Console I/O

Debug/diagnostics

Disk

Internal processes

File system

Memory

NetWare Loadable Module (NLM) or external processes

Queue Management Series (QMS)

Due to the abundance of messages, this AppNote will highlight messages 
originating from three of the functional categories. 

Disk

Memory

Accounting and statistics


Severity

In addition to functionality, the messages can also be categorized by 
severity. Severity refers to the amount of potential damage that could be 
caused by the condition the message is reporting. The different classes of 
severity are as follows:  
        

Fatal/Abend         - Resource fatally affected; server shut down

Warning             - Configuration errors, and so on. No damage.

Informational       - Indicates attained thresholds; includes counters and
                    gauges.

Recoverable         - Hot Fix disk, and so on. Workaround made. 

Critical            - Disk mirror failure, and so on. Fix-up attempted. 

Operation-Aborted   - Operation cannot complete; cause unknown.               
                     
   
The first three classes are very common and may appear frequently, while the 
last three rarely occur. The focus of this AppNote will center on the first 
three.

Fatal/Abend

Fatal/Abend (ABnormal-END) The majority of NetWare 386 operating system 
messages are of the Fatal/Abend type. Fatal/Abend messages are usually caused
by consistency check errors but can also be caused by insufficient resources 
such as memory, DMA or interrupts.              

Fatal/Abend messages are displayed in the form:                              

ABEND: < message > 

Consistency check errors are internal tests placed in the Netware operating 
system. The primary function of these tests is to ensure the stability and 
integrity of internal operating system data. There are numerous consistency 
checks interlaced throughout Netware which validate critical processes such 
as disk, memory and communications.

The primary cause of consistency check errors is aberrations in the operating
system. An operating system as large and complex as NetWare 386 statistically
can contain software errors. Consistency checks identify these errors, as 
well as the potential for serious operating system corruption, and intervene 
by halting the system. Consistency check errors inform the administrator of 
the serious problem that has occurred and allow a diagnostic dump of the 
server operating system's memory to be performed.

This diagnostic dump, along with information detailing the events which led 
to the abend, allow the re-creation and location of the problem, and enable 
the creation of a patch in a timely manner. 

Other causes of consistency check errors include corrupt operating system 
files, drivers, NetWare Loadable Modules (NLMs) or hardware failures. They 
could be the result of defective memory chips, static discharges, faulty 
power supplies, power surges or spikes.

Warning messages

Warning messages are also common. These messages inform the administrator of 
potential problems caused by improper system configuration; a very desirable 
service. Messages of this type do not indicate damage and the correction is 
usually simple and straightforward.

Informational messages

Informational messages were implemented due to the complexity and variety of 
tasks that may be performed by NetWare. These messages provide a window on 
the status of NetWare. They both inform and alert the administrator of 
completed operations, processes, and attained thresholds. The informational 
message does not indicate system damage but instead, has the responsibility 
of notifying the administrator of the state of the system.

Recovery from consistency check errors

NetWare 386 is very resilient, but consistency check errors can and will 
arise. If any consistency check error occurs repeatedly, check the CPU board,

memory, power supplies, and power conditioning equipment. Replace any faulty 
hardware. If continued failure persists, reinstall the operating system, 
drivers or NLMs from the master diskettes.


Error Messages

*** 16 Bit Multiply Failure ***
NETWARE 386 CANNOT RUN CORRECTLY ON THIS MACHINE!!!
(contact your PC supplier for a new revision 386 microprocessor)

Process:    Memory

Severity:   Fatal/Abend

Explanation:  During initialization the system performs several simple 
hardware checks on the file server. These checks include whether the machine 
is a PS2, and what type of CPU is in the computer (8088, 8086 or 80386). This
error occurred because the system failed to pass a 16 bit multiplication 
problem. The response returned by the CPU didn't match the expected result.

Action: This indicates a bug in the 80386 CPU. NetWare will not run on this 
machine because it doesn't handle 16 bit operations correctly. Try another 
computer as the file server.

*** 32 Bit Multiply Failure ***
NETWARE 386 CANNOT RUN CORRECTLY ON THIS MACHINE!!!
(contact your PC supplier for a new revision 386 microprocessor)

Process:    Memory

Severity:   Fatal/Abend

Explanation: When the system is first initializing it does some simple 
hardware checks on the file server. These checks include whether the machine 
is a PS2, what type of CPU is in the computer (8088, 8086 or 80386). This 
error occurred because the system failed to pass a 32 bit multiplication 
problem. The answer given by the CPU didn't match the expected result.

Action: This indicates a bug in the 80386 CPU. NetWare will not run on this 
machine because it doesn't handle 32 bit operations correctly. Try another 
computer as the file server.


*** This machine does not have an 80386 microprocessor ***
NETWARE 386 CANNOT BE RUN ON THIS MACHINE!!!

Process:    Memory

Severity:   Fatal/Abend

Explanation: Before initialization can take place the OS checks to see if the
machine it's about to be run on does in fact have an 80386 microprocessor.

Action: A 386 CPU is required in order to execute NetWare 386. NetWare 386 
makes use of 32 bit registers and memory. 


A wait node was lost by the TTS support code.

Process:    Disk

Severity:   Fatal/Abend

Explanation: An internal process in the Netware Operating System detected a 
lost timing object or wait node. Wait nodes are created and destroyed by the 
operating system as needed. The role of the wait node is much like a library 
card. Wait nodes are created to keep track of the start and end of internal 
processes. After closing an inactive TTS transaction and reallocating the 
memory the system checks for lost timing objects (wait nodes). If any are 
missing this error will occur, because wait nodes are destroyed in an orderly
fashion at the completion of the process it was tracking. This error is the 
result of a failed internal consistency check.

Action: See the information on consistency checks at the beginning of this 
document.


Aborted remirror of partition # <number> partitionnumber

Process:    Disk

Severity:   Fatal/Abend

Explanation: While remirroring a disk partition, the system found the 
remirroring process to be out of sync, due to hardware failure.

Action: Make sure disk configuration is correct. Check and replace any faulty
disk controller(s), cable(s) or drive(s).


Alloc called at interrupt time

Process:    Memory

Severity:   Fatal/Abend

Explanation: While trying to allocate memory, the system checked the status 
of the nested interrupt counter (count of how many interrupts are currently 
being processed) and found the counter's value to be greater than zero. The 
system abended because the memory allocation procedure required the number of
nested interrupts to be zero.

Action: See the information on consistency checks at the beginning of this 
document.


Alloc called with invalid resource tag

Process:    Memory

Severity:   Fatal/Abend

Explanation: While initializing and allocating memory, the system checked the
memory allocation signature (the descriptor or code of the memory it was 
trying to allocate at the time) against the resource tag signature (the 
memory type the system expects to allocate) and found they didn't match.

Action: See the information on consistency checks at the beginning of this 
document.


AllocateBlock found an invalid cache buffer

Process:    Disk
Severity:   Fatal/Abend

Explanation: An internal process in the Netware OS attempted to allocate a 
block of memory for use that was already in use by another process. This 
error is the result of a failed internal consistency check.

Action: See the information on consistency checks at the beginning of this 
document.


AllocateNonMovableReturnableMemory discovered an invalid memory block segment

Process:    Disk

Severity:   Fatal/Abend

Explanation: An internal process in the Netware operating system, requested a
block of non-moveable returnable memory. The memory-linked lists (tables 
containing data with pointers referring to the next entry in the list, much 
like the DOS FAT table) were searched for an available block and an invalid 
memory link was found. This indicates corrupt memory-linked lists. This error
is the result of a failed internal consistency check.

Action: See the information on consistency checks at the beginning of this 
document.


AllocatePermanentMemory called at interrupt time

Process:    Memory

Severity:   Fatal/Abend

Explanation: The system tried to allocate memory while the nested interrupt 
counter (used to track interrupts currently being used for processes) had a 
value greater than zero. This routine requires the nested counter to be zero.

Action: See the information on consistency checks at the beginning of this 
document.


AllocatePermanentMemory discovered an invalid memory block segment

Process:    Disk

Severity:   Fatal/Abend

Explanation: When the system attempted to allocate memory, the memory segment
found was larger than the expected memory segment size. The memory segment 
pointers were corrupt. This error is the result of a failed internal 
consistency check.

Action: See the information on consistency checks at the beginning of this 
document. 

AllocateReturnableMemory called with invalid resource tag

Process:    Disk

Severity:   Fatal/Abend

Explanation: The pointers defining the type of memory to be allocated were 
found to be corrupt. The resource tag signature (a descriptor issued by the 
OS to track system resources) didn't match the memory signature to be 
allocated.

Action: See the information on consistency checks at the beginning of this 
document.


AllocateWaitNode found an invalid wait node on the avail list

Process:    Disk

Severity:   Fatal/Abend

Explanation: The pointer tracking the next available waiting object (used to 
establish a timing interval between memory and transactions) in the 
multitasking kernel was found to be corrupt.

Action: See the information on consistency checks at the beginning of this 
document.


AllocNonMovableCacheMemory called with an invalid resource tag

Process:    Disk

Severity:   Fatal/Abend

Explanation: The system attempted to allocate the wrong type of memory. The 
resource tag signature didn't match the expected memory signature.

Action: See the information on consistency checks at the beginning of this 
document.


AllocNonMovableCacheMemory did a bad calculation

Process:    Disk

Severity:   Fatal/Abend

Explanation: The system was establishing 4KB blocks of non-movable cache 
memory blocks in response to a system request. An abend occurred because the 
amount of memory requested, after 4KB boundary and memory waste calculations,
was less than the expected amount. The tables governing memory allocation 
have been corrupt.
Action: See the information on consistency checks at the beginning of this 
document.


AllocPermMemory got an invalid resource tag

Process:    Memory

Severity:   Fatal/Abend

Explanation: While attempting to allocate memory, the system checked if the 
resource tag (a descriptor used to track resources) assigned was of the 
correct type. It wasn't.

Action: See the information on consistency checks at the beginning of this 
document.


AllocSemiPermMemory got an invalid resource tag

Process:    Memory

Severity:   Fatal/Abend

Explanation: Before allocating semi-permanent memory, the system checked the 
resource tag signature (used to identify a resource) against the 
semi-permanent memory signature. They didn't match. The resource tag (used to
track resources) assigned to this memory was of the wrong type or was 
corrupt.

Action: See the information on consistency checks at the beginning of this 
document.


Already being used on SetBeingUsed in disk cache

Process:    Disk

Severity:   Fatal/Abend

Explanation: The counter used to keep track of disk cache semaphores in the 
disk routine was corrupt. A count of one was expected, but when the system 
tested the counter's value, it was greater than one. This indicates use by 
another process. This error should not have occurred because the routine that
sets the counter is called or initiated by the checking routine.

Action: See the information on consistency checks at the beginning of this 
document.


Attempt to reuse logicalpartition number detected in 
AssignLogicalPartitionNumber 

Process:    Disk
Severity:   Fatal/Abend

Explanation: While attempting to assign a logical partition number, the 
system checked the logical partition mapping table contents and found a value
other than zero. The table had not been initialized properly.

Action: See the information on consistency checks at the beginning of this 
document. 


Attempt to reuse partition number detected in AssignDeviceNumber

Process:    Disk

Severity:   Fatal/Abend

Explanation: While attempting to assign a disk device number, the system 
checked the device mapping table contents and found a value other than zero. 
The table had not been initialized properly.

Action: See the information on consistency checks at the beginning of this 
document.


Attempt to reuse partition number detected in AssignPartitionNumber

Process:    Disk

Severity:   Fatal/Abend

Explanation: While attempting to assign a logical partition number, the 
system checked the partition mapping table contents and found a value other 
than zero. The table had not been initialized properly.

Action: See the information on consistency checks at the beginning of this 
document.


Attempt to reuse partition number detected in AssignSystemNumber

Process:    Disk

Severity:   Fatal/Abend

Explanation: While attempting to assign a disk system number, the system 
checked the system mapping table contents and found a value other than zero. 
The table had not been initialized properly.

Action: See the information on consistency checks at the beginning of this 
document.     


Attempt to reuse partition number detected in AssignHandleNumber

Process:    Disk

Severity:   Fatal/Abend

Explanation: While attempting to issue a disk handle number, the system found
the handle mapping table to be corrupt.

Action: See the information on consistency checks at the beginning of this 
document.


Bit map overrun in CheckBitMap

Process:    Disk

Severity:   Fatal/Abend

Explanation: While checking the status of a bit map, the parameters passed to
the routine were too large. If, for example, a bit map of the primary disk 
represented 1,000 sectors, an overrun would occur if the parameters sent to 
the routine were for 1,003 sectors. The error can also occur when the bit map
table is corrupt.

Action: See the information on consistency checks at the beginning of this 
document.


Bit map overrun in CheckDiskBitMap

Process:    Disk

Severity:   Fatal/Abend

Explanation: While checking a range of bits in a disk bit map, the parameters
passed to the routine were too large. If, for example, a bit map of the 
primary disk represented 1,000 sectors, an overrun would occur if the 
parameters sent to the routine were for 1,003 sectors. The error can also 
occur when the bit map table is corrupt.

Action: See the information on consistency checks at the beginning of this 
document.


Bit map overrun in ClearBitMap

Process:    Disk

Severity:   Fatal/Abend

Explanation: While clearing or resetting a specific bit in a bit map,  the 
parameters passed to the routine were too large. If, for example, a bit map 
of the primary disk represented 1,000 sectors, an overrun would occur if the 
parameters sent to the routine were for 1,003 sectors. The error can also 
occur when the bit map table is corrupt.
Action: See the information on consistency checks at the beginning of this 
document.


Bit map overrun in ClearDiskBitMap

Process:    Disk

Severity:   Fatal/Abend

Explanation: While clearing or resetting a range of bits in a disk bit map 
the parameters passed to the routine were too large. If, for example, at bit 
map of the primary disk represented 1,000 sectors, an overrun would occur if 
the parameters sent to the routine were for 1,003 sectors. The error can also
occur when the bit map table is corrupt.

Action: See the information on consistency checks at the beginning of this 
document.


Bit map overrun in SetBitMap

Process:    Disk

Severity:   Fatal/Abend

Explanation: While setting a specific bit in a bit map, the parameters  
passed to the routine were too large. If, for example, a bit map of the 
primary disk represented 1,000 sectors, an overrun would occur if the 
parameters sent to the routine were for 1,003 sectors. The error can also 
occur when the bit map table is corrupt.

Action: See the information on consistency checks at the beginning of this 
document.


Bit map overrun in SetDiskBitMap

Process:    Disk

Severity:   Fatal/Abend

Explanation: While setting (to turn on) a range of bits in a disk bit map the
parameters passed to the routine were too large. If, for example, a bit map 
of the primary disk represented 1,000 sectors, an overrun would occur if the 
parameters sent to the routine were for 1,003 sectors. The error can also 
occur when the bit map table is corrupt.

Action: See the information on consistency checks at the beginning of this 
document.


Bit map overrun in UnSetDiskBitMap

Process:    Disk

Severity:   Fatal/Abend

Explanation: While unsetting (to turn off) a range of bits in a disk bit map,
the parameters passed to the routine were too large. If, for example, a bit 
map of the primary disk represented 1,000 sectors, an overrun would occur if 
the parameters sent to the routine were for 1,003 sectors. The error can also
occur when the bit map table is corrupt.

Action: See the information on consistency checks at the beginning of this 
document.


Cache buffer being removed from drive index not found in disk cache

Process:    Disk

Severity:   Fatal/Abend                   

Explanation: The pointer to the next cache block entry was corrupt. The 
system expected to find another entry, but it did not. Therefore the system 
abended. This error is the result of a failed internal consistency check.

Action: See the information on consistency checks at the beginning of this 
document. 


Cache buffer not found in drive table or avail list by 
AllocateNonMovableReturnableMemory

Process:    Disk

Severity:   Fatal/Abend

Explanation: The system attempted to allocate non-movable returnable memory, 
but could not find expected memory on any list. This error is the result of a
failed internal consistency check.

Action: See the information on consistency checks at the beginning of this 
document. 


Cache buffer not found in drive table or avail list by 
AllocateReturnableMemory

Process:    Disk

Severity:   Fatal/Abend

Explanation: The system attempted to allocate returnable memory, but could 
not find the expected memory on any list. This error is the result of a 
failed internal consistency check.

Action: See the information on consistency checks at the beginning of this 
document. 


Cache Buffer was lost

Process:    Disk

Severity:   Fatal/Abend

Explanation: The system checked the available cache buffer list. Available 
buffers should have been found, but the list contained zero buffer entries.

Action: Reinitialize the system. If the problem persists, add more memory to 
server.


CacheNonMovableMemoryCleanUp detected a lost memory segment

Process:    Disk

Severity:   Fatal/Abend

Explanation: The system deallocated non-movable memory and cleaned up 
(restored to previous state) the used memory locations and resource tags. 
While checking the memory resource tag count, the system found there were 
still memory resources checked out and unaccounted for. This error is the 
result of a failed internal consistency check.

Action: See the information on consistency checks at the beginning of this 
document. 


CheckMemory first block fragment not pointing to the Header

Process:    Memory

Severity:   Fatal/Abend

Explanation: While attempting to allocate memory, the system's memory block 
validity check failed. The beginning of the memory block was not aligned with
the memory block header. The system abended because the linked list tracking 
memory block allocation was corrupt.

Action: See the information on consistency checks at the beginning of this 
document.


CheckMemory found an available fragment not on the avail list

Process:    Memory

Severity:   Fatal/Abend

Explanation: While checking known memory blocks for consistency, the system 
found a block fragment that was not listed on the available memory block 
list. This indicates corrupt memory pointers.

Action: See the information on consistency checks at the beginning of this 
document.


CheckMemory found a block that ended incorrectly

Process:    Memory

Severity:   Fatal/Abend

Explanation: While the system was allocating memory, the system checked the 
end of the block against the logical end stored in the linked list and found 
they didn't match.

Action: See the information on consistency checks at the beginning of this 
document.


CheckMemory found a fragment with an invalid node length

Process:    Memory

Severity:   Fatal/Abend

Explanation: While allocating memory, the system found that the next 
available memory block was not the proper size. The system gathers pieces of 
memory together to form blocks. It checked the next block against the first 
block known to be correct and found they didn't match. The size of the tested
block could have been bigger or smaller than what was expected. Other 
routines should have set the correct size of the block. This error indicates 
data structure corruption.

Action: See the information on consistency checks at the beginning of this 
document.


CheckMemory found contiguous fragments not pointing to each other

Process:    Memory

Severity:   Fatal/Abend

Explanation: The next available memory block was tested against the logical 
end of the linked list and was found to have the incorrect value. The linked 
list of memory blocks was corrupt.

Action: See the information on consistency checks at the beginning of this 
document.


CheckMemory found that LastNodePointer was invalid

Process:    Memory

Severity:   Fatal/Abend

Explanation: While gathering memory fragments for block allocation, the 
system checked the end of the available memory list with the logical memory 
end and found they didn't match. This indicates a corrupt linked list.

Action: See the information on consistency checks at the beginning of this 
document.


CheckMemory found that the avail list ends improperly

Process:    Memory

Severity:   Fatal/Abend

Explanation: After scanning through the memory block list, the system found 
that the last available memory blocks header didn't have the correct value. 
This indicates corrupt memory pointers.

Action: See the information on consistency checks at the beginning of this 
document.


CheckMemory found two nodes on the Avail list that do not point to each other

Process:    Memory

Severity:   Fatal/Abend

Explanation: During a memory allocation procedure, the system found two 
blocks of memory that were not properly linked. The last available or last 
used memory block's end pointer did not point to the beginning of the next 
available memory block.

Action: See the information on consistency checks at the beginning of this 
document.


Could not find block with redirection bit set in UpdateRequest

Process:    Disk

Severity:   Fatal/Abend

Explanation: While trying to update a disk block for redirection in the hash 
table, the system could not find a block that had been marked for 
redirection.

Action: See the information on consistency checks at the beginning of this 
document.


Could not find block with redirection bit set in RedirectThisBlock

Process:    Disk

Severity:   Fatal/Abend

Explanation: While redirecting data to the Hot Fix redirection area, the 
system could not find a block in the area that had been marked for 
redirection.

Action: See the information on consistency checks at the beginning of this 
document.


Could not find block with redirection bit set

Process:    Disk

Severity:   Fatal/Abend

Explanation: While trying to locate a data block for redirected data in the 
hash table, the system could not find a block that had been marked for 
redirection.

Action: See the information on consistency checks at the beginning of this 
document.


Could not redirect block <number> on partition # <number>

Process:    Disk

Severity:   Informational

Explanation: The system was unable to redirect data during a Hot Fix 
operation due to  insufficient space.

Action: Increase the Hot Fix redirection area through the INSTALL program. 
The Hot Fix area should contain at least two percent of the entire disk 
space.


Device handle was not found on resource list

Process:    Disk

Severity:   Fatal/Abend

Explanation: While attempting to release a disk device handle from use, the 
system scanned the resource tag linked list and could not find the device 
listed. This indicates that the linked list that is tracking handle resources
was corrupt.

Action: See the information on consistency checks at the beginning of this 
document.


Device I/Os pending on handle release

Process:    Disk

Severity:   Fatal/Abend

Explanation: While in the final check to release a disk device handle, the 
system detected I/Os pending and aborted the release. The linked list that is
tracking device handles was corrupt.

Action: See the information on consistency checks at the beginning of this 
document.


Device was not in list when SynchronizedDeleteDiskDevice was called

Process:    Disk

Severity:   Fatal/Abend

Explanation: Information pertaining to the disk was not in the disk device 
list when the call to delete its information was made.

Action: See the information on consistency checks at the beginning of this 
document.


DiskRead invalid use count

Process:    Disk

Severity:   Fatal/Abend

Explanation: While decrementing the use count after a disk read, the system 
detected  that the use count fell below zero. This error is the result of a 
failed internal consistency check.

Action: See the information on consistency checks at the beginning of this 
document. 


DiskRelease invalid use count

Process:    Disk

Severity:   Fatal/Abend

Explanation: While decrementing the use count upon releasing a disk after a  
transaction, the system found that the counter fell below zero. A count below
zero indicates corruption in the pointers used to track disk use activity. 
This error is the result of a failed internal consistency check.

Action: See the information on consistency checks at the beginning of this 
document.


DiskWrite invalid use count

Process:    Disk

Severity:   Fatal/Abend

Explanation: While decrementing the use count, after writing a dirty cache 
block to disk, the counter's value fell below zero. A count below zero 
indicates corrupt pointers tracking the disk cache use counter. This error is
the result of a failed internal consistency check.

Action: See the information on consistency checks at the beginning of this 
document.


Error allocating memory for disk initialization

Process:    Disk

Severity:   Fatal/Abend

Explanation: Upon initialization of the disk, the allocation of permanent 
memory for the disk was checked and found to be null.

Action: Add more memory to the file server.


Error closing executable file

Process:    Memory

Severity:   Fatal/Abend            

Explanation: After successfully reading SERVER.EXE into memory, the system 
attempted to close the file and could not. It then exited back to DOS without
closing the file properly. This could be caused by a damaged file, a bad disk
or faulty hardware. 

Action: Check the integrity of the file with a file utility. Make sure the 
disk system which is used to load the executable is functioning properly; 
replace any faulty hardware.


Error getting memory for disk caching

Process:    Disk
Severity:   Fatal/Abend

Explanation: An error occurred while attempting to initialize the cache. 
After trying to retrieve some permanent memory for the request, the system 
returned zero blocks allocated. Any of the following could cause the error: 
faulty memory, hardware failure, insufficient memory. 

Action: Check the hardware. Add more memory to the server.


Error opening executable file

Process:    Memory

Severity:   Fatal/Abend

Explanation: After the system verified that it is running on the proper 
equipment, it tried to load the rest of SERVER.EXE and failed. It then exited
to DOS.

Action: The DOS open file function failed with this error, indicating the 
file couldn't be found, was damaged or there were an insufficient amount of 
file handles available. Make sure the executable file is in the correct drive
and is functional .


Error reading executable file

Process:    Memory

Severity:   Fatal/Abend

Explanation: After the system has verified that it is running on the proper 
equipment, it opened SERVER.EXE, then tried to read the file and failed.

Action: The read file function failed with this error, indicating the file 
was damaged or couldn't be accessed properly for some reason. Make sure the 
executable file is in the correct drive and is functional. 


ErrorLog invalid use count

Process:    Disk

Severity:   Fatal/Abend

Explanation: While scanning all volumes and cache buffers for errors, the 
system detected an error. The system logged the error and attempted to 
decrement the use count (like a sign in sheet, which tells the system 
something is being used, such as a buffer). The counter's value fell below 
zero, indicating corrupt pointers tracking the error log use counter. This 
error is the result of a failed internal consistency check.

Action: See the information on consistency checks at the beginning of this 
document.


ExpandMemory discovered an invalid memory block segment

Process:    Disk

Severity:   Fatal/Abend

Explanation: When the system attempted to expand allocated memory, the newly 
selected memory overlapped the current segment. This indicates corrupt memory
pointers.

Action: See the information on consistency checks at the beginning of this 
document. 


ExpandMemory was given an invalid memory block

Process:    Disk

Severity:   Fatal/Abend

Explanation: When the system was expanding allocated memory, the memory block
that was selected for addition to the current segment was found to have an 
invalid resource tag This indicates corrupt memory segment pointers or 
corrupt resource pointers.

Action: See the information on consistency checks at the beginning of this 
document.


Free called at interrupt time

Process:    Memory

Severity:   Fatal/Abend

Explanation: The Free memory procedure (used to clear and clean up memory 
after use) was called while the nested interrupt counter was greater than 
zero. This memory procedure requires the nested count to be zero.

Action: See the information on consistency checks at the beginning of this 
document.


Free called with a memory block that has an invalid resource tag

Process:    Memory

Severity:   Fatal/Abend

Explanation: While attempting to put a freed block of memory back on the free
list, the system found that the resource allocation tag (used to track 
resources) of the memory block didn't match the resource signature. This 
indicates corrupt resource tracking pointers.

Action: See the information on consistency checks at the beginning of this 
document.


GetRequest was called with an invalid device handle

Process:    Disk

Severity:   Fatal/Abend

Explanation: During a disk request, the system found that the physical disk 
stamp ID didn't match the device handle ID. The data structures tracking 
device handles (logical numbers issued by the system which relates to disk 
devices) were corrupt.

Action: See the information on consistency checks at the beginning of this 
document.


Insufficient memory to run NetWare 386
(requires at least 1 megabyte of extended memory)

Process:    Memory

Severity:   Fatal/Abend

Explanation: One of the first steps before SERVER.EXE can be loaded is to 
check the total amount of server RAM available. The system first checks the 
amount of extended ram. If it's greater than or equal to 1MB, initialization 
will continue; otherwise the system will exit to DOS.

Action: The minimum amount of RAM needed to start a NetWare 386 system is 
1.64MB of  RAM, (one MB Extended / 640KB Conventional). NetWare 386 uses RAM 
dynamically (it takes what it needs, as it needs it; then returns the RAM 
when not in use). Therefore, under heavy workload conditions or when the 
system has large disks, it is advisable to increase server RAM accordingly. A
good RAM base to start from would be 4MB.


InternalDiskGet invalid use count

Process:    Disk

Severity:   Fatal/Abend

Explanation: While decrementing the use count, after requesting a disk 
transaction, the use counter's value fell below zero. This indicates corrupt 
pointers tracking the disk request use counter.

Action: See the information on consistency checks at the beginning of this 
document.

InternalDiskRelease invalid use count

Process:    Disk

Severity:   Fatal/Abend

Explanation: Following the release of a disk after a transaction, the use 
count was  decremented to a value below zero. This indicates corruption in 
the pointers used to track disk activity. This error is the result of a 
failed internal consistency check.

Action: See the information on consistency checks at the beginning of this 
document. 


InternalDiskUpdate invalid use count

Process:    Disk

Severity:   Fatal/Abend

Explanation: After updating the disk from cache, the system attempted to 
decrement the use count. The system found that the counter fell below zero, 
indicating corrupt memory pointers. 

Action: See the information on consistency checks at the beginning of this 
document. 


Invalid device handle in DiskDeviceCleanUpRoutine

Process:    Disk

Severity:   Fatal/Abend

Explanation: While attempting to release a disk device, the system found that
the device handle previously issued did not match the expected device number.
This indicates corrupt resource tracking.

Action: See the information on consistency checks at the beginning of this 
document.


Invalid device number passed to LogicalParitionRequest

Process:    Disk

Severity:   Fatal/Abend            

Explanation: The partition stamp number did not match the logical disk stamp 
number. The pointers tracking disk devices and partitions were corrupt.      

Action: See the information on consistency checks at the beginning of this 
document.


Invalid device used by request in PhysicalRequest

Process:    Disk

Severity:   Fatal/Abend

Explanation: The pointers tracking physical disk devices were deemed corrupt 
by the OS after a check against the physical device stamp list failed.

Action: See the information on consistency checks at the beginning of this 
document.


Invalid logical partition handle in DiskLogicalPartitionCleanUpRoutine

Process:    Disk

Severity:   Fatal/Abend

Explanation: When the system attempted to dismount a volume, the disk logical
partition handle number did not match the logical partition type number. The 
data structure tracking handle devices was corrupt.

Action: See the information on consistency checks at the beginning of this 
document.


Invalid memory block given to AllocateAddMemory

Process:    Memory

Severity:   Fatal/Abend

Explanation: While gathering memory for an allocation request, the system 
tested the size of the new block against the parameters set for block 
allocation and found it to be greater than expected.

Action: See the information on consistency checks at the beginning of this 
document.


Invalid mirror in linked list

Process:    Disk

Severity:   Fatal/Abend

Explanation: While scanning mirror information tables and checking the 
validity of logical mirrors, the system found a logical mirror entry that 
should not exist on the linked list. The linked list of logical mirror 
information was corrupt.
Action: See the information on consistency checks at the beginning of this 
document.


Invalid partition handle in DiskPartitionCleanUpRoutine

Process:    Disk

Severity:   Fatal/Abend

Explanation: The handle number passed to the routine to clean up disk 
partitions was of the wrong type. The internal mechanism for issuing 
partition handle numbers was  corrupt.

Action: See the information on consistency checks at the beginning of this 
document.


Invalid partition number return at ReturnDeviceNumber

Process:    Disk

Severity:   Fatal/Abend

Explanation: While creating, deleting or mirroring a disk partition, the 
system found that the device mapping table was corrupt. The number in the 
table didn't match the expected physical disk number.

Action: See the information on consistency checks at the beginning of this 
document.


Invalid partition number return at ReturnHandleNumber

Process:    Disk

Severity:   Fatal/Abend

Explanation: While attempting to reclaim a previously issued partition handle
number, the system found it to be of the wrong type when it was passed to the
return handle number routine.

Action: See the information on consistency checks at the beginning of this 
document.


Invalid partition number return at ReturnLogicalPartitionNumber

Process:    Disk

Severity:   Fatal/Abend

Explanation: While creating, deleting or mirroring a disk partition, the 
system found that the logical partition mapping table was corrupt. The number
in the table didn't match the expected logical disk partition number.

Action: See the information on consistency checks at the beginning of this 
document.


Invalid partition number return at ReturnPartitionNumber

Process:    Disk

Severity:   Fatal/Abend

Explanation: While creating, deleting or mirroring a disk partition, the 
system found that the partition mapping table was corrupt. The number in the 
table didn't match the expected disk partition number.

Action: See the information on consistency checks at the beginning of this 
document.


Invalid partition number return at ReturnSystemNumber

Process:    Disk

Severity:   Fatal/Abend

Explanation: While creating, deleting or mirroring a disk partition, the 
operating system found that the system mapping table was corrupt. The number 
in the table didn't match the expected system pointer number.

Action: See the information on consistency checks at the beginning of this 
document.


Invalid request returned NPut-IOCTL

Process:    Disk

Severity:   Fatal/Abend

Explanation: The I/O control list pointers became corrupt and returned a zero
while the system was performing a scan. (IOCTL- is the entry point for I/O 
control requests).

Action: See the information on consistency checks at the beginning of this 
document.


Invalid resource tag passed to AddDiskSystem

Process:    Disk

Severity:   Fatal/Abend

Explanation: When the system checked the resource tag signature the resource 
tag signature did not match the disk driver signature. This indicates corrupt
resource tracking.

Action: See the information on consistency checks at the beginning of this 
document.


Invalid resource tag passed to DeviceLock

Process:    Disk

Severity:   Fatal/Abend

Explanation: While attempting to lock a disk device, the system found that 
the resource tag for the device did not match the disk device signature. 
Either the signature on the drive or the internal resource tag tables are 
corrupt.

Action: See the information on consistency checks at the beginning of this 
document.


Invalid resource tag passed to LogicalPartitionLock

Process:    Disk

Severity:   Fatal/Abend

Explanation: The resource tag signature did not match the disk logical 
partition lock signature. The pointers governing disk resource tags are 
corrupt.

Action: See the information on consistency checks at the beginning of this 
document.


Invalid resource tag passed to PartitionLock

Process:    Disk

Severity:   Fatal/Abend

Explanation: When the system attempted to lock a logical partition (used by 
NetWare), the resource tag, which the system passed to the lock partition 
function did not match the disk partition signature. A logical partition 
might be locked by an NLM such as INSTALL or VREPAIR or by a volume dismount.
This indicates corrupt resource tracking pointers.

Action: See the information on consistency checks at the beginning of this 
document.


Invalid resource tag passed to SystemLock
Process:    Disk

Severity:   Fatal/Abend

Explanation: When the system attempted a system lock, the resource tag passed
an invalid parameter to the system lock routine. The tag type didn't match 
what the system expected. The pointer's tracking resource allocation have 
been corrupted.

Action: See the information on consistency checks at the beginning of this 
document.


Invalid system handle in DiskSystemCleanUpRoutine

Process:    Disk

Severity:   Fatal/Abend

Explanation: While attempting to release a disk system, the OS found the 
device type handle previously issued did not match the expected system type 
number.

Action: See the information on consistency checks at the beginning of this 
document. 


Invalid system ID passed to GetIOCTL

Process:    Disk

Severity:   Fatal/Abend

Explanation: When the system attempted an I/O control request, the system 
found the  disk system list pointers to be corrupt. The disk system stamp did
not match the system stamp.

Action: See the information on consistency checks at the beginning of this 
document.


Invalid system ID passed to NPutIOCTL

Process:    Disk

Severity:   Fatal/Abend

Explanation: When the system attempted to issue an I/O control request, a 
check of the system device table stamp ID against the system stamp failed. 
(Stamp, IOCTL)

Action: See the information on consistency checks at the beginning of this 
document.


Invalid System ID passed to DeviceIOCTLRequest

Process:    Disk

Severity:   Fatal/Abend

Explanation: While attempting an I/O control request, the system found the 
device  mapping table pointers to be corrupt. 

Action: See the information on consistency checks at the beginning of this 
document.


Invalid System ID passed to SystemIOCTLRequest

Process:    Disk

Severity:   Fatal/Abend

Explanation: While scanning the system mapping table's device list, the 
system found the pointers to be corrupt. 

Action: See the information on consistency checks at the beginning of this 
document.


Invalid parity in linked list

Process:    Disk

Severity:   Fatal/Abend

Explanation: This error message is one of a group of messages associated with
a function that has not yet been implemented: disk parity checking. This form

of error checking is usually done at the hardware level, but Novell is 
working on a software enhancement that will be functional at a later date. 
After implementation, this message will indicate linked list corruption.

Action: See the information on consistency checks at the beginning of this 
document. 


Loading . . .

Process:    Memory

Severity:   Informational

Explanation: This is an informational message which is displayed at the file 
server console after executing SERVER.EXE, and while SERVER.EXE is loaded 
into memory.

Action: None. 


Logical Partition handle was not found on resource list

Process:    Disk

Severity:   Fatal/Abend

Explanation: While releasing a logical partition, the system found the linked
list governing partition handle information to be corrupt.

Action: See the information on consistency checks at the beginning of this 
document.


Logical Partition I/Os pending on handle release

Process:    Disk

Severity:   Fatal/Abend

Explanation: While attempting to release a logical partition, the system 
found there were still I/Os pending and aborted the release. By the time this
function is called, I/Os should not be pending. They all should have been 
flushed from cache and written to disk.

Action: See the information on consistency checks at the beginning of this 
document.


No dirty bits found in cache buffer on dirty list in disk cache

Process:    Disk

Severity:   Fatal/Abend

Explanation: While attempting to write a dirty cache buffer, the system 
checked the buffer's dirty status. It did not find the expected bits turned 
on, which indicates the buffer is dirty. This buffer's dirty bits should have
been set in the on position.

Action: See the information on consistency checks at the beginning of this 
document.


Object not found for inform in disk cache

Process:    Disk

Severity:   Fatal/Abend

Explanation: When the system checked one of its cache data structures, the 
structure's value was zero. The value should have been higher. The data 
structures tracking either cache objects or dirty cache buffers waiting to be
written to disk were corrupt. 

Action: See the information on consistency checks at the beginning of this 
document. 


Out of memory allocating diskrequest

Process:    Disk

Severity:   Fatal/Abend

Explanation: While attempting a disk request, the system's check for 
allocated permanent memory  found the memory to be insufficient.

Action: NLMs or other processes have used all available memory. Rebooting the
server should temporarily restore the system to full functionality. If this 
or any other memory-related error recurs, the server may require additional 
memory.


Out of memory for request structure in HotfixBlockingIO

Process:    Disk

Severity:   Fatal/Abend

Explanation: The system attempted to build a data structure to use in a Hot 
Fix operation. The system abended due to lack of memory resources.

Action: The possibility exists that NLMs or internal processes used needed 
memory resources. Rebooting the file server should fix the problem. If the 
problem persists, add more memory to the file server and then reboot.


Parition I/Os pending on handle release

Process:    Disk

Severity:   Fatal/Abend

Explanation: The system attempted to release a locked partition, but found 
there were pending I/Os. The partition lock table was corrupt.

Action: See the information on consistency checks at the beginning of this 
document.


Parity requests not implemented yet

Explanations:   This error message is one of a group of messages associated 
with a function that has not yet been implemented: disk parity checking. This
form of error checking is usually done at the hardware level, but Novell is 
working on a software enhancement that will be functional at a later date. 
After implementation, this message will indicate linked list corruption.

Action: See the information on consistency checks at the beginning of this 
document.


Partition handle was not found on resource list

Process:    Disk

Severity:   Fatal/Abend

Explanation: While releasing a partition handle, the system found the linked 
list governing partition handle information to be corrupt.

Action: See the information on consistency checks at the beginning of this 
document.


PhysicalRequest returned an error in HotfixBlockingI/O

Process:    Disk

Severity:   Fatal/Abend

Explanation: Physical Request returned an error because an area alleged to be
safe for redirection was faulty. The system tried to access data, which had 
been redirected by Hot Fix but was unable to. This is an indication of a 
potentially bad disk. 

Action: Use the MONITOR utility to check the  status of redirected blocks. If
the problem persists: 

1. Backup data  

2. Surface test or format the disk

3. Increase Hot Fix redirection area (make sure at lease two percent of the
total disk size is allocated for redirection.)

4. Create the volume(s)

5. Restore the data


ReturnAllocResourceTag caught a resource tag out of sync with memory

Process:    Memory

Severity:   Fatal/Abend

Explanation: After the system deallocated and cleaned up all memory 
resources, a check of memory resources, found a discrepancy. The system 
abended because the pointer's tracking memory resources were corrupt.

Action: See the information on consistency checks at the beginning of this 
document.


ReturnAllocResourceTag was given an invalid resource tag

Process:    Memory

Severity:   Fatal/Abend

Explanation: When the system was deallocating memory, the current resource 
tag didn't have the expected resource allocation signature. The system 
abended because the resource allocation lists were corrupt.

Action: See the information on consistency checks at the beginning of this 
document.


ReturnMemory discovered an invalid memory block segment

Process:    Disk

Severity:   Fatal/Abend

Explanation: After returning some memory to cache, the system detected 
overlapping memory segments, indicating corrupt memory pointers.

Action: See the information on consistency checks at the beginning of this 
document.


ReturnMemory was given an invalid memory block

Process:    Disk

Severity:   Fatal/Abend

Explanation: The system attempted to return some memory to cache. After a 
check, it discovered the memory it was attempting to move was the wrong 
memory. The resource tag of the memory to be returned didn't match the 
resource signature, indicating corrupt memory or resource pointers.

Action: See the information on consistency checks at the beginning of this 
document. 


ReturnNonMovableMemory called with an invalid return segment

Process:    Disk

Severity:   Fatal/Abend

Explanation: Before deallocating a returnable, non-moveable block of memory 
to cache, the system found that the memory it was attempting to move was not 
the memory type expected. This indicates corrupt memory resource pointers.

Action: See the information on consistency checks at the beginning of this 
document.


ReturnPermanentMemory called at interrupt time

Process:    Memory

Severity:   Fatal/Abend

Explanation: The system tried to return memory while the nested interrupt 
counter's value was greater than zero. This routine requires the nested 
counter's value to be zero.

Action: See the information on consistency checks at the beginning of this 
document. 


ReturnPermanentMemory couldn't find the block on the resource list

Process:    Memory

Severity:   Fatal/Abend

Explanation: While attempting to return some memory, the system couldn't find
the resource tag of the current block of memory in the resource list. The 
linked list tracking memory resources was corrupt.

Action: See the information on consistency checks at the beginning of this 
document.


ReturnPermanentMemory received an invalid memory block

Process:    Memory

Severity:   Fatal/Abend

Explanation: Before attempting to return some permanent memory, the system 
checked the resource tag and found it to be invalid. The resource tag issued 
to the returning memory did not match the semi-permanent memory signature, 
indicating a corrupt resource tag.

Action: See the information on consistency checks at the beginning of this 
document.


ReturnWaitNode was given an un-allocated wait node

Process:    Disk
Severity:   Fatal/Abend

Explanation: The wait-node data structures should have had a value of zero, 
but had a value greater than zero. This indicates corruption in the wait-node
data structures. 

Action: See the information on consistency checks at the beginning of this 
document.


Semi-permanent memory allocator is out of memory <number> semi-permanent 
memory allocation requests failed

Process:    Memory

Severity:   Operation-Aborted

Explanation: While attempting to satisfy a request for an amount of memory, 
the system found it did not have enough memory to complete the request. 

Action: Power down the system, add more memory to the file server and reboot 
the system.


SemiPermanentMemory clean up procedure found an incorrect resource block list

Process:    Memory

Severity:   Fatal/Abend

Explanation: After an NLM unloaded, the system found an inconsistency in the 
resource list while attempting a memory clean up procedure. During the unload
process, the OS will deallocate, or return, the memory used by the NLM to the
cache pool. During this procedure the OS verifies that all memory blocks have
been accounted for. After the system thought it had cleaned up all memory 
blocks, it checked the resource tag count for its value and found it to be 
greater than zero. This indicates the resource linked list or the counter was
corrupt.

Action: See the information on consistency checks at the beginning of this 
document.


Short term memory allocator is out of memory <number> attempts to get more 
memory failed

Process:    Memory

Severity:   Operation-Aborted

Explanation: While allocating memory the system found it had no more memory 
available for allocation. The memory pool was empty or there weren't any free
memory blocks available. This is not fatal, the system simply did not 
complete the operation.
Action: More memory is needed. Add memory to the server or unload some 
unneeded NLMs.


System handle was not found on resource list

Process:    Disk

Severity:   Fatal/Abend

Explanation: When a system lock is performed, a resource tag and a system 
handle are issued for the procedure. When the lock was going to be released, 
the system scanned the resource table and found that the system handle wasn't
on the list, indicating a corrupt table.

Action: See the information on consistency checks at the beginning of this 
document.


System I/Os pending on handle release

Process:    Disk

Severity:   Fatal/Abend

Explanation: The system was attempting to release a system lock. The resource
was set for release, but I/Os were still pending on the resource. This 
indicates that the table governing system locks was corrupt.

Action: See the information on consistency checks at the beginning of this 
document.


System not in list when FSAddDiskDevice was called

Process:    Disk

Severity:   Fatal/Abend

Explanation: While adding a disk to the system, the OS could not find the 
expected disk in the disk system table. The disk system table was corrupt.

Action: See the information on consistency checks at the beginning of this 
document.


System was not found on resource list

Process:    Disk

Severity:   Fatal/Abend

Explanation: While attempting to remove a disk from the system, the OS found 
that the disk to be removed was not listed as a resource.
Action: See the information on consistency checks at the beginning of this 
document.


System was not in list when FSAddDiskCard was called

Process:    Disk

Severity:   Fatal/Abend

Explanation: While adding a disk card to the system, the system list was 
scanned for driver information pertaining to the card. The system expected to
receive this information, yet it was not found on the system list. This 
indicates corrupt system list pointers.

Action: See the information on consistency checks at the beginning of this 
document.


System was not in list when FSDeleteDiskCard was called

Process:    Disk

Severity:   Fatal/Abend

Explanation: While deleting a disk card from the system, the system list was 
scanned for driver information pertaining to the card. The system expected to
receive this information, yet it was not found on the system list. This 
indicates corrupt system list pointers.

Action: See the information on consistency checks at the beginning of this 
document.


TTS invalid use count

Process:    Disk

Severity:   Fatal/Abend

Explanation: After the system released a wait node, used in a TTS 
transaction, the use  count, was decremented. The system found that the 
counter fell below zero, which indicates corrupt pointers to the use counter.

Action: See the information on consistency checks at the beginning of this 
document.


TTSGuaranteeWait was passed an invalid wait node

Process:    Disk

Severity:   Fatal/Abend

Explanation: The system tried to establish a new wait node for a TTS 
transaction. But when the system checked the wait node list to confirm that 
it was empty, it found a value greater than zero. This indicates that the 
pointer tracking the data structure containing waiting objects, was corrupt.

Action: See the information on consistency checks at the beginning of this 
document.


Unable to open file NET$ACCT.DAT to add audit record

Process:    Accounting and Statistics

Severity:   Operation-Aborted

Explanation: The system tried to append an audit record to the system 
accounting audit file and the lock on NET$ACCT.DAT failed. The file is either
stuck in a locked position or it was corrupt. 

Action: First establish the status of the file. Use MONITOR to determine if 
the file is locked or not. If the file is locked, make sure you have a recent
backup of the system. Run  BINDFIX and re-boot the server. If the file is 
corrupt:                                  

1. Restore file from a backup, or

2. Delete NET$ACCT.DAT (all previous accounting information stored in the old
NET$ACCT.DAT will be lost.) When the file is deleted a new one will be
created when the system requests an append.


UnCloneMirrorGroup was called

Process:    Disk

Severity:   Fatal/Abend

Explanation: A clone is a data structure created to track I/Os of a device 
that has been removed or is non-functional. This usually relates to mirrored 
disk devices. This abend occurred because of a lack of memory resources for 
the data structures.

Action: Other processes in the server have used up all the available 
resources. Rebooting the server should clear up the problem. But if this or 
messages with similar memory caused abends frequently occur, add more memory 
to the server.


UnCloneParityGroup was called

Process:    Disk

Severity:   Fatal/Abend

Explanation: This error message is one of a group of messages associated with
a function that has not yet been implemented: disk parity checking. This form
of error checking is usually done at the hardware level, but Novell is 
working on a software enhancement that will be functional at a later date. 
After implementation, this message will indicate a malfunction in the disk 
mirroring portion of the OS.

Action: This message usually indicates the server needs more memory. 
Rebooting the server, limiting the number of NLMs loaded, or adding more 
memory to the server are some possible solutions.


WARNING: There are no more redirection blocks

Process:    Disk

Severity:   Warning

Explanation: After retrieving the amount of data redirection blocks 
available, the system found the quantity to be zero. Running out of 
redirection blocks is a symptom of a failing disk system. Either the disk or 
controller is in distress. 

Action: Back up the disk system in question. Check the entire disk system and
determine which component is at fault. Run any necessary utilities in order 
to diagnose the potential disk problem. If the hardware is functioning 
correctly load INSTALL and increase the Hot Fix redirection area. The area 
should contain at least two percent of the total disk capacity. 


WARNING: There are only <number> redirection blocks left

Process:    Disk

Severity:   Warning

Explanation: After retrieving the amount of data redirection blocks 
available, the system found the quantity to be insufficient. The amount 
available is compared against the minimum redirection blocks allowed. This 
message is a threshold warning.

Action: Back up the disk system in question. Check the entire disk system and
determine which component is at fault. Run any necessary utilities in order 
to diagnose the potential disk problem. If the hardware is functioning 
correctly load INSTALL and increase the Hot Fix redirection area. The area 
should contain at least two percent of the total disk capacity. 


Glossary

Bit maps

A bit map is like an overall view of what the disk area looks like. They are 
similar to disk bit map in that bits are set on and off to track changes in 
data, but differ because bit maps are for specific sectors while disk bit 
maps are for sector ranges. Bit maps are used for the Hot Fix process as well
as remirroring. They track changes in redirected data and provide 
synchronization for mirroring. 

Dirty cache buffer

Data stored in a temporary ram buffer before it's sent to disk.

Dirty status

Whether or not a chunk of data has been written to disk recently or not. 
Indicates whether this block of data includes changes that are not reflected 
by the disk copy of the block.

Disk bit maps

A disk bit map is like an overall view of what the disk area looks like. It 
is used for the Hot Fix process as well as remirroring. Each bit represents a
4KB block. Bits are set on or off to track changes in redirected data and 
provide synchronization for mirroring. Disk bit maps cover ranges of the disk
while bit maps are for specific sectors.

Disk logical partition handle number

A number issued by a routine which is used by the system for identification 
of logical partitions.

IOCTL

An entry point for I/O control requests.

Linked list

A table or list of items with pointers that indicate the beginning, end and 
next entry in the list.

Logical partition type number

A previously defined number which uniquely identifies a type of resource. In 
this case a logical partition.

Memory allocation signature

A unique ID for each memory block.

Memory block header

Information pertaining to a block of memory, for example. its size, location 
in the linked list, and so on.

Memory linked lists

A table of pointers interconnecting blocks of memory, much like the DOS FAT 
table.

Nested interrupt counter

A count of how many interrupts are currently being processed.

Resource signature

A predefined, unique ID identifying a resource, used in resource allocation 
and cleanup routines to ensure resource validity.

Resource tag

A descriptor issued by the system to resources, in order to track their use.

Semi-permanent memory signature

An ID used in identifying resources, in this case semi-permanent memory.

Signature

A unique ID which specifically identifies a resource.

Stamp

A code used to identify a device or resource to the system.

Waiting object

Used to establish a timing interval between memory and transactions. It is 
used to make processes wait their turn.

System lock

A routine used to lock resources, such as disk or partitions, so that users 
or NLMs can register to use the resource.

Use count

Like a sign-in sheet, it tells the system something such as a buffer is being
used, so other processes won't interfere with the transaction.

