Document revision date: 30 March 2001
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OpenVMS System Management Utilities Reference
Manual
The value of DEFQUEPRI should be less than or equal to MAXQUEPRI.
Note
DEFQUEPRI refers to relative queue scheduling priority, not the
execution priority of the job.
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DEVICE_NAMING
(Alpha only) DEVICE_NAMING is a bit mask indicating whether port
allocation classes are used in forming SCSI device names.
Following is the bit definition:
Bit |
Definition |
0
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If 1, enable new naming.
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1
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Must be 0. This bit is reserved for use by Compaq.
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For more information about port allocation classes, see OpenVMS Cluster Systems.
DISABLE_UPCALLS (D)
DISABLE_UPCALLS is primarily a debugging aid. It allows the system
manager to disable threads upcalls of specific types for the entire
system. The value is a bit mask, with the bits corresponding to the
upcall types. The upcall types are defined in the definition macro
$TMCDEF.
This special parameter is used by Compaq and is subject to change. Do
not change this parameter unless Compaq recommends that you do so.
DISK_QUORUM (D)
The DISK_QUORUM parameter is the name of an optional quorum disk in
ASCII. ASCII spaces indicate that no quorum disk is being used.
DLCKEXTRASTK
(VAX only) DLCKEXTRASTK specifies the amount of extra interrupt stack
(in bytes) to leave when doing a deadlock search.
This parameter is not used on Alpha systems.
This special parameter is used by Compaq and is subject to change. Do
not change this parameter unless Compaq recommends that you do so.
DNVOSI1
DNVOSI1 is reserved to DECnet-Plus for OpenVMS. This special parameter
is used by Compaq and is subject to change. Do not change this
parameter unless Compaq recommends that you do so.
DORMANTWAIT (D)
DORMANTWAIT specifies, in seconds, the amount of time that can elapse
without a significant event before the system treats a low-priority
computable process as a DORMANT process for scheduling purposes. (A
low-priority process is a non real-time process whose current priority
is equal to or less than the value specified by the system parameter
DEFPRI [default=4].) After SUSP (suspended) processes, DORMANT
processes are the most likely candidates for memory reclamation by the
swapper.
Increasing the value of DORMANTWAIT can increase the interval that a
low priority process blocks a high priority process if that low
priority process is holding a lock or resource that the higher priority
process is waiting for.
DR_UNIT_BASE (G)
(Alpha only) DR_UNIT_BASE specifies the base value from which unit
numbers for DR devices (DIGITAL StorageWorks RAID Array 200 Family
logical RAID drives) are counted.
DR_UNIT_BASE provides a way for unique RAID device numbers to be
generated. DR devices are numbered starting with the value of
DR_UNIT_BASE and then counting from there. For example, setting
DR_UNIT_BASE to 10 produces device names such as $1$DRA10, $1$DRA11,
and so on.
Setting DR_UNIT_BASE to appropriate, nonoverlapping values on all
cluster members that share the same (nonzero) allocation class ensures
that no two RAID devices are given the same name.
DUMPBUG
DUMPBUG enables (1) or disables (0) the writing of error log buffers
and memory contents to SYS$SYSTEM:SYSDUMP.DMP when a fatal bugcheck
occurs. This parameter should be off (0) only when the executive is
being debugged.
DUMPSTYLE (A,D)
DUMPSTYLE specifies the method of writing system dumps.
DUMPSTYLE is a 32-bit mask, with the following bits defined. Each bit
can be set independently. The value of the system parameter is the sum
of the values of the bits that have been set. Remaining or undefined
values are reserved for Compaq use only.
Bit |
Mask |
Description |
0
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00000001
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0 =
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Full dump (SYSGEN default). The entire contents of physical memory are
written to the dump file.
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1 =
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Selective dump. The contents of memory are written to the dump file
selectively to maximize the usefulness of the dump file while
conserving disk space.
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1
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00000002
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0 =
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Minimal console output.
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1 =
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Full console output (includes stack dump, register contents, and so on).
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2
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00000004
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0 =
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Dump to system disk.
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1 =
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Dump off system disk (DOSD) to an alternate disk. (Refer to the
OpenVMS System Manager's Manual for details.)
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3 (Alpha only)
1
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00000008
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0 =
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Do not compress.
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1 =
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Compress. (See note below.)
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4 - 14
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Reserved for Compaq use only.
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15 (VAX only)
2
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00008000
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0 =
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Disable use of bits 16 - 27.
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1 =
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Enable use of bits 16 - 27.
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16 - 27 (VAX only)
2
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0FFF0000
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Range of DOSD unit numbers.
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28 - 31
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Reserved for Compaq use only.
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1VAX systems do not support dump compression.
2Specific to VAX 7000s.
If you plan to enable the Volume Shadowing minimerge feature on an
Alpha system disk, be sure to specify DOSD to an alternate disk.
Note
On Alpha systems, you can save space on the system disk and, in the
event of a crash, save time recording the system memory, by using the
OpenVMS Alpha dump compression feature. Unless you override the default
AUTOGEN calculations (by setting DUMPSTYLE in MODPARAMS.DAT), AUTOGEN
uses the following algorithm:
- On a system with less than 128 MB of memory, the system sets the
DUMPSTYLE to 1 (a raw selective dump) and sizes the dump file
appropriately.
- On a system with 128 MB of memory or greater, the system sets the
DUMPSTYLE to 9 (a compressed selective dump), and creates the dump file
at two-thirds the value of the corresponding raw dump.
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Examples:
The mask of 00000006 directs the system to send a full dump, with full
console output, off the system disk (to the alternate disk).
For a VAX 7000, a mask of 00098006 directs the system to send a full
dump with full console output to the DOSD whose unit number is 9.
On Alpha systems, the mask of 00000009 directs the system to compress a
selective dump with minimal console output.
ERLBUFFERPAGES (A on Alpha)
ERLBUFFERPAGES specifies the amount of memory to allocate for each
buffer requested by the ERRORLOGBUFFERS parameter.
On VAX systems, ERLBUFFERPAGES has a default value of 2 pages and a
maximum value of 32 pages.
On Alpha systems, ERLBUFFERPAGES has a default value of 4 pagelets and
a maximum value of 32 pagelets.
ERRORLOGBUFFERS
ERRORLOGBUFFERS specifies the number of buffers reserved for system
error log entries. Each buffer is ERLBUFFERPAGES in length. If
ERRORLOGBUFFERS is too low, messages might not be written to the error
log file. If it is too high, unneeded physical pages can be consumed by
the error log buffers.
If you increase ERRORLOGBUFFERS, you must also increase the size of the
system dump file.
EXPECTED_VOTES (A)
EXPECTED_VOTES specifies the maximum number of votes that may be
present in a cluster at any given time. Set it to a value that is equal
to the sum of the vote parameters of all cluster members, plus any
votes that are contributed by the quorum disk. This value is used to
automatically derive the number of votes that must be present for the
cluster to function (quorum).
EXTRACPU (D)
EXTRACPU sets the time, in units of 10 milliseconds, allotted to each
of a process's exit handlers (for each access mode) after the process
times out (that is, reaches its CPU time limit).
EXUSRSTK
EXUSRSTK specifies the amount of space provided by the image activator
to recover from a stack overflow error.
This special parameter is used by Compaq and is subject to change. Do
not change this parameter unless Compaq recommends that you do so.
FAST_PATH
(Alpha only) FAST_PATH is a static system parameter that enables (1) or
disables (0) the Fast Path performance features for all Fast
Path-capable ports.
Starting in OpenVMS Version 7.2, FAST_PATH is enabled by default. In
Versions 7.0 and 7.1, FAST_PATH was disabled by default.
For additional information, see FAST_PATH_PORTS and IO_PREFER_CPUS.
FAST_PATH_PORTS
(Alpha only) FAST_PATH_PORTS is a static parameter that deactivates
Fast Path for specific drivers.
FAST_PATH_PORTS is a 32-bit mask. If the value of a bit in the mask is
1, Fast Path is disabled for the driver corresponding to that bit. A
value of -1 specifies that Fast Path is disabled for all drivers that
the FAST_PATH_PORTS parameter controls.
Bit position zero controls Fast Path for PKQDRIVER (for parallel SCSI),
and bit position one controls Fast Path for FGEDRIVER (for Fibre
Channel). Currently, the default setting for FAST_PATH_PORTS is 0,
which means that Fast Path is enabled for both PKQDRIVER and FGEDRIVER.
In addition, note the following:
- CI drivers are not controlled by FAST_PATH_PORTS. Fast Path for CI
is enabled and disabled exclusively by the FAST_PATH system parameter.
- FAST_PATH_PORTS is relevant only if the FAST_PATH system parameter
is enabled (equal to 1). Setting FAST_PATH to zero has the same effect
as setting FAST_PATH_PORTS to -1.
For additional information, see FAST_PATH and IO_PREFER_CPUS.
FREEGOAL (A,D,M)
FREEGOAL establishes the number of pages that you want to reestablish
on the free-page list following a system memory shortage. Memory
shortages occur when the system drops below the minimum number of pages
required on the free-page list (FREELIM). The value of FREEGOAL must
always be greater than or equal to the value of FREELIM.
FREELIM (A,M)
FREELIM sets the minimum number of pages that must be on the free-page
list.
The system writes pages from the modified-page list, swaps out working
sets, or reduces the size of the working sets to maintain the minimum
count.
While the larger free-page list generally means less page I/O, it also
means less space for the balance set, which tends to result in more
swap I/O. You can monitor the size of the free-page list, the amount of
page, and the amount of swap with the MONITOR IO command of the Monitor
utility.
GALAXY
(Alpha Galaxy platforms only) The GALAXY parameter controls whether the
specified instance participates in a Galaxy sharing set. Specify one of
the following:
Value |
Description |
0
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Never load. Do not participate in a Galaxy sharing set.
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1
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Always load. Participate in a Galaxy sharing set.
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The default value is 0. GALAXY is not an AUTOGEN parameter.
GBLPAGES (A,D,F,G,M)
GBLPAGES sets the number of global page table entries allocated at
bootstrap time. Each global section requires 1 global page table entry
per section page, plus 2 entries, with the total rounded up to an even
number.
Users with CMKRNL privilege can change this parameter on a running
system. Increasing the value of this parameter allows the global page
table to expand, on demand, up to the maximum size.
The default value is sufficient for the images normally installed as
shared in the system startup command procedures. Once the system is
running and all global sections are created, you can examine the actual
requirements with the /GLOBAL qualifier of the Install utility
(INSTALL) and reduce the value of GBLPAGES accordingly. However, do not
set the value of this parameter too low, because the page table entries
use little permanently resident memory. If you plan to install many
user images as shared, or if user programs are likely to create many
global sections, you must increase the value of this parameter.
GBLPAGFIL (A,D)
GBLPAGFIL defines the maximum number of systemwide pages allowed for
global page-file sections (scratch global sections that can be used
without being mapped to a file). These global page-file sections can be
temporary, permanent, system, or group, and are allocated from the page
file specified in the system process header at bootstrap time. When you
allow pages for global page-file sections, you must increase the size
of the page file accordingly. Users with CMKRNL privilege can change
this parameter value on a running system.
Global page-file sections are created with the Create and Map Section
system services ($CREATE_GPFILE, $CRMPSC, and $CRMPSC_GPFILE_64)
without an explicit disk file. These sections are used for the RMS
global buffers required for shared files. Users of shared files should
note that global page-file sections cause both the global page table
and the default system page file (PAGEFILE.SYS) to be used. If the
value of GBLPAGFIL is too small, $CRMPSC issues an error message when
you attempt to create global page-file sections.
You must have scratch global sections if you use RMS global buffers.
Each file using global buffers requires, in the system page file, the
file's bucket size multiplied by the number of global buffers for that
file. If the file's bucket size varies, as with RMS indexed files, use
the maximum bucket size. For shared sequential files, use the
multiblock count of the first stream to perform the $CONNECT service in
place of the file's bucket size.
The default value for this parameter is adequate for most systems.
However, if your site uses RMS global buffering to a significant
extent, you may need to raise the value of GBLPAGFIL. Use the /GLOBAL
qualifier of the Install utility to examine the number of pages
consumed by RMS global buffers. The global sections used by RMS for
global buffers have the prefix RMS$ followed by 8 hexadecimal digits.
Global buffers are enabled with the DCL command SET
FILE/GLOBAL_BUFFERS, which is described in the OpenVMS DCL Dictionary.
GBLSECTIONS (A,F,G,M)
GBLSECTIONS sets the number of global section descriptors allocated in
the system header at bootstrap time. Each global section requires one
descriptor. Each descriptor takes 32 bytes of permanently resident
memory.
The default value is sufficient for the images normally installed as
shared in the system startup command procedures. Once the system is
running and all global sections are created, you can examine the actual
requirements with the /GLOBAL qualifier of the Install utility and
reduce the value of GBLSECTIONS accordingly. However, the value of this
parameter should not be set too low. If you plan to install many user
images as shared, or if user programs are likely to create many global
sections, you must increase the value of this parameter.
If the value of GBLSECTIONS is too small, you receive a message from
the Install utility at system startup time or whenever you install
images manually. Note that too large a value for GBLSECTIONS wastes
physical memory.
GH_EXEC_CODE (A,F)
(Alpha only) GH_EXEC_CODE specifies the size in pages of the execlet
code granularity hint region.
GH_EXEC_DATA (A,F)
(Alpha only) GH_EXEC_DATA specifies the size in pages of the execlet
data granularity hint region.
GH_RES_CODE (A,F)
(Alpha only) GH_RES_CODE specifies the size in pages of the resident
image code granularity hint region.
GH_RES_DATA (A,F)
(Alpha only) GH_RES_DATA specifies the size in pages of the resident
image data granularity hint region.
GH_RSRVPGCNT (F)
GH_RSRVPGCNT specifies the number of pages in the resident image
granularity hint region that the Install utility can use after the
system has finished booting.
If bit 2 of the LOAD_SYS_IMAGES parameter is set, the image LDR$WRAPUP
releases all unused pages in the granularity hint region at the the end
of system startup. The unused pages of the resident image granularity
hint region are either reserved for future use, or given back to the
free memory list.
GH_RSRVPGCNT specifies the number of pages that LDR$WRAPUP attempts to
leave in the resident image granularity hint region. If the
GH_RSRVPGCNT number of pages is larger than the unused pages in the
granularity hint region, the region is not expanded to accommodate the
number of pages requested.
GLX_INST_TMO
(Alpha Galaxy platforms only) GLX_INST_TMO is the time (in
milliseconds) that an instance in a Galaxy sharing set can fail to
increment its timeout value before the other sharing instances presume
that the instance failed and remove it from the sharing set.
The default is 20,000 milliseconds (20 seconds).
GLX_SHM_REG
For Galaxy systems, GLX_SHM_REG is the number of shared memory region
structures configured into the Galaxy Management Database (GMDB). If
set to 0, the default number of shared memory regions are configured.
GROWLIM (A,D,M)
GROWLIM sets the number of pages that the system must have on the
free-page list so that a process can add a page to its working set when
it is above quota. GROWLIM has no effect if the process is below its
working set quota. GROWLIM acts as a fast shutoff to the working set
extent mechanism based on the system's free memory.
IEEE_ADDRESS
IEEE_ADDRESS is reserved for Compaq use only.
IEEE_ADDRESSH
IEEE_ADDRESSH is reserved for Compaq use only.
IJOBLIM (D)
IJOBLIM sets the maximum number of interactive jobs that can be on the
system concurrently. You can control the maximum number of concurrent
interactive users on the system with the DCL command SET
LOGINS/INTERACTIVE.
IMGIOCNT
IMGIOCNT specifies the default number of pages of image I/O address
space to be allocated for the image activator if not specified at
program link time.
This special parameter is used by Compaq and is subject to change. Do
not change this parameter unless Compaq recommends that you do so.
IMGREG_PAGES
(Alpha only) IMGREG_PAGES is the number of pages to reserve in P1 space
for images to be installed with shareable address data. If IMGREG_PAGES
is set to 0, no images are installed with shared address data. The
default is 10,000 pages.
For more information, see the INSTALL section in the OpenVMS System Management Utilities Reference Manual.
INTSTKPAGES (A,D,G,M)
(VAX only) INTSTKPAGES sets the size of the interrupt stack in pages.
Each page on the interrupt stack requires a page of permanently
resident memory.
Use the default value of 6 unless interrupt-stack-not-valid exceptions
occur. These may be caused by either an unusually large number of
devices or a driver that requires a large amount of stack space.
IO_PREFER_CPUS
(Alpha only) IO_PREFER_CPUS is a dynamic system parameter that controls
the set of CPUs that are available for use as Fast Path preferred CPUs.
IO_PREFER_CPUS is a CPU bit mask specifying the CPUs that are allowed
to serve as preferred CPUs and that can thus be assigned a Fast Path
port. CPUs whose bit is set in the IO_PREFER_CPUS bit mask are enabled
for Fast Path port assignment. IO_PREFER_CPUS defaults to -1, which
specifies that all CPUs are allowed to be assigned Fast Path ports.
You might want to disable the primary CPU from serving as a preferred
CPU by clearing its bit in IO_PREFER_CPUS. This reserves the primary
CPU for non-Fast-Path IO operations to use.
Changing the value of IO_PREFER_CPUS causes the FASTPATH_SERVER process
to execute the automatic assignment algorithm that spreads Fast Path
ports evenly among the new set of usable CPUs.
For additional information, see FAST_PATH and FAST_PATH_PORTS.
IOTA
IOTA specifies the amount of time (in 10-millisecond units) to charge
to the current residence quantum for each voluntary wait. The correct
value approximates the cost of a disk I/O neglecting wait time.
This special parameter is used by Compaq and is subject to change. Do
not change this parameter unless Compaq recommends that you do so.
JBOBLIM
This parameter is no longer in use.
JOBCTLD
System managers do not usually alter JOBCTLD; this word of debug flags
is used in rolling upgrades of OpenVMS. If bit 0 is set, the queue
manager does not start. The default is 0.
This special parameter is used by Compaq and is subject to change. Do
not change this parameter unless Compaq recommends that you do so.
KFILSTCNT
KFILSTCNT is no longer used on VAX systems and is not used on Alpha
systems.
KSTACKPAGES
(Alpha only) KSTACKPAGES controls the number of pages allocated for
process kernel stacks.
LAMAPREGS (G)
(VAX only) LAMAPREGS sets the number of UNIBUS map registers allocated
to an LPA11 driver when the driver is loaded, and limits the registers
for the driver to that number. A value of 0 permits dynamic allocation
of an unlimited number of registers.
LAN_FLAGS (D)
(Alpha only) LAN_FLAGS is a bit mask used to enable features in the
local area networks port drivers and support code. The default value
for LAN_FLAGS is 0.
The bit definitions are as follows:
Bit |
Description |
Bit 0
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The default of zero indicates that ATM devices run in SONET mode. If
set to 1, this bit indicates ATM devices run in SDH mode.
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Bit 1
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If set, this bit enables a subset of the ATM trace and debug messages
in the LAN port drivers and support code.
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Bit 2
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If set, this bit enables all ATM trace and debug messages in the LAN
port drivers and support code.
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Bit 3
1
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If set, this bit runs UNI 3.0 over all ATM adapters.
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Bit 4
1
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If set, this bit runs UNI 3.1 over all ATM adapters.
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Bit 5
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If set, disables autoconfiguration over all Gigabit Ethernet Adapters.
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Bit 6
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If set, enables the use of jumbo frames over all Gigabit Ethernet
Adapters.
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1Auto-sensing of the ATM UNI version is enabled if both bit
3 and bit 4 are off (0).
LCKMGR_MODE
(Alpha only) The LCKMGR_MODE parameter controls usage of the dedicated
CPU lock manager. The dedicated CPU lock manager performs all locking
operations on a single dedicated CPU. This can improve system
performance on large SMP systems with high MP_Synch associated with the
lock manager.
Utilizing this feature requires additional setup besides just setting
this parameter. For more information about usage and setup of the
dedicated CPU lock manager, see the OpenVMS Version 7.3 New
Features manual.
Specify one of the following values:
Value |
Description |
0
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Automatic. Let the Lock Manager decide the appropriate mode. This is
currently done by CPU count. 5 or more result in the use of the
dedicated CPU Lock Manager.
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1
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On. Run Lock Manager on dedicated CPU.
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2
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Off (default). Run the traditional Lock Manager.
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LGI_BRK_DISUSER (D)
LGI_BRK_DISUSER turns on the DISUSER flag in the UAF record when an
attempted break-in is detected, thus permanently locking out that
account. The parameter is off (0) by default. You should set the
parameter (1) only under extreme security watch conditions, because it
results in severely restricted user service.
LGI_BRK_LIM (D)
LGI_BRK_LIM specifies the number of failures that can occur at login
time before the system takes action against a possible break-in. The
count of failures applies independently to login attempts by each user
name, terminal, and node. Whenever login attempts from any of these
sources reach the break-in limit specified by LGI_BRK_LIM, the system
assumes it is under attack and initiates evasive action as specified by
the LGI_HID_TIM parameter.
The minimum value is 1. The default value is usually adequate.
LGI_BRK_TERM (D)
LGI_BRK_TERM causes the terminal name to be part of the association
string for the terminal mode of break-in detection. When LGI_BRK_TERM
is set to off (0), the processing considers the local or remote source
of the attempt, allowing break-in detection to correlate failed access
attempts across multiple terminal devices. When set to on (1),
LGI_BRK_TERM assumes that only local hard-wired or dedicated terminals
are in use and causes breakin detection processing to include the
specific local terminal name when examining and correlating break-in
attempts.
Ordinarily, LGI_BRK_TERM should be set to off (0) when physical
terminal names are created dynamically, such as when network protocols
like LAT and Telnet are in use.
LGI_BRK_TMO (D)
LGI_BRK_TMO specifies the length of the failure monitoring period. This
time increment is added to the suspect's expiration time each time a
login failure occurs. Once the expiration period passes, prior failures
are discarded, and the suspect is given a clean slate.
LGI_CALLOUTS (D)
LGI_CALLOUTS specifies the number of installation security policy
callout modules to be invoked at each login. LGI_CALLOUTS must be set
to 0 unless callout modules are present.
LGI_HID_TIM (D)
LGI_HID_TIM specifies the number of seconds that evasive action
persists following the detection of a possible break-in attempt. The
system refuses to allow any logins during this period, even if a valid
user name and password are specified.
LGI_PWD_TMO (D)
LGI_PWD_TMO specifies, in seconds, the period of time a user has to
enter the correct system password (if used). LGI_PWD_TMO also
establishes the timeout period for users to enter their personal
account passwords at login time. Also, when using the SET PASSWORD
command, LGI_PWD_TMO specifies the period of time the system waits for
a user to type in a new password, an old password, and the password
verification.
LGI_RETRY_LIM (D)
LGI_RETRY_LIM specifies the number of retry attempts allowed users
attempting to log in. If this parameter is greater than 0, and a
legitimate user fails to log in correctly because of typing errors, the
user does not automatically lose the carrier. Instead (provided that
LGI_RETRY_TMO has not elapsed), by pressing the Return key, the user is
prompted to enter the user name and password again. Once the specified
number of attempts has been made without success, the user loses the
carrier. As long as neither LGI_BRK_LIM nor LGI_BRK_TMO has elapsed,
the user can dial in again and reattempt login.
LGI_RETRY_TMO (D)
LGI_RETRY_TMO specifies the number of seconds allowed between login
retry attempts after each login failure. (Users can initiate login
retries by pressing the Return key.) This parameter is intended to be
used with the LGI_RETRY_LIM parameter; it allows dialup users a
reasonable amount of time and number of opportunities to attempt logins
before they lose the carrier.
LNMPHASHTBL (A on VAX,G)
LNMPHASHTBL sets the size of the process logical name hash table.
Logical names are hashed using a function of the name length and
contents. The LNMPHASHTBL parameter determines the number of entries
for process-private logical names. The recommended setting is the
average number of process-private logical names. Note that the hashed
values are rounded up to the nearest power of 2.
LNMSHASHTBL (A,F,G)
LNMSHASHTBL sets the size of the system logical name hash table.
Logical names are hashed using a function of the name length and
contents. The LNMSHASHTBL parameter determines the number of entries
for shareable logical names. These names include all names from the
system, group, and job logical name tables. The recommended setting
allows one to four logical names per hash table entry. The default
setting is usually adequate, unless your installation has a large
number of groups, or many jobs are active simultaneously. In that case,
an increase in the value of the next higher power of 2 might improve
logical name translation performance. Note that the hashed values are
rounded up to the nearest power of 2.
LOAD_PWD_POLICY
LOAD_PWD_POLICY controls whether the SET PASSWORD command attempts to
use site-specific password policy routines, which are contained in the
shareable image SYS$LIBRARY:VMS$PASSWORD_POLICY.EXE. The default is 0,
which indicates not to use policy routines.
LOAD_SYS_IMAGES (A on Alpha)
This special parameter is used by Compaq and is subject to change. Do
not change this parameter unless Compaq recommends that you do so.