bmc-watchdog(8) System Commands bmc-watchdog(8)
NAME
bmc-watchdog - BMC watchdog timer daemon and control utility
SYNOPSIS
bmc-watchdog command [OPTION...] [COMMAND_OPTIONS...]
DESCRIPTION
bmc-watchdog controls a Baseboard Management Controller (BMC) watchdog timer. The bmc-watchdog tool typically executes as a cronjob or dae-
mon to manage the watchdog timer. A user must be root in order to run bmc-watchdog.
Listed below are bmc-watchdog details, option details, examples, and known issues. For a general introduction to FreeIPMI please see
freeipmi(7).
BMC WATCHDOG DETAILS
A BMC watchdog timer is part of the Intelligent Platform Management Interface (IPMI) specification and is only available to BMCs that are
compliant with IPMI. When a BMC watchdog timer is started, it begins counting down to zero from some positive number of seconds. When the
timer hits zero, the timer will execute a pre-configured pre-timeout interrupt and/or timeout action.
In order to stop the pre-timeout interrupt or timeout action from being executed, the watchdog timer must be periodically reset back to its
initial beginning value.
The BMC watchdog timer automatically stops itself when the machine is rebooted. Therefore, when a machine is brought up, the BMC watchdog
timer must be setup again before it can be used.
Typically, a BMC watchdog timer is used to automatically reset a machine that has crashed. When the operating system first starts up, the
BMC timer is set to its initial countdown value. At periodic intervals, when the operating system is functioning properly, the watchdog
timer can be reset by the OS or a userspace program. Thus, the timer never counts down to zero. When the system crashes, the timer cannot
be reset by the OS or userspace program. Eventually, the timer will countdown to zero and reset the machine.
See EXAMPLES below for examples of how bmc-watchdog is commonly used.
COMMANDS
The following commands are available to bmc-watchdog.
-s, --set
Set BMC Watchdog Configuration. BMC watchdog timer configuration values can be set using the set command options listed below under
SET OPTIONS. If a particular configuration parameter is not specified on the command line, the current configuration of that parame-
ter will not be changed.
-g, --get
Get BMC Watchdog Configuration and State. The current configuration and state is printed to standard output.
-r, --reset
Reset BMC Watchdog Timer.
-t, --start
Start BMC Watchdog Timer. Does nothing if the timer is currently running. Identical to --reset command when the timer is stopped
with the exception of the start command options listed below under START OPTIONS.
-y, --stop
Stop BMC Watchdog Timer. Stops the current timer.
-c, --clear
Clear BMC Watchdog Configuration. Clears all configuration values for the watchdog timer, except for timer use, which is kept at its
current value.
-d, --daemon
Run bmc-watchdog as a daemon. Configurable BMC watchdog timer options are listed below under DAEMON OPTIONS. The configuration val-
ues are set once, then the daemon will reset the timer at specified periodic intervals. The daemon can be stopped using the --stop
command, --clear command, or by setting the stop_timer flag on the --set command.
GENERAL OPTIONS
The following options are general options for configuring IPMI communication and executing general tool commands. These options are
generic and can be used by any command.
-D IPMIDRIVER, --driver-type=IPMIDRIVER
Specify the driver type to use instead of doing an auto selection. The currently available inband drivers are KCS, SSIF, OPENIPMI,
and SUNBMC.
--disable-auto-probe
Do not probe in-band IPMI devices for default settings.
--driver-address=DRIVER-ADDRESS
Specify the in-band driver address to be used instead of the probed value. DRIVER-ADDRESS should be prefixed with "0x" for a hex
value and '0' for an octal value.
--driver-device=DEVICE
Specify the in-band driver device path to be used instead of the probed path.
--register-spacing=REGISTER-SPACING
Specify the in-band driver register spacing instead of the probed value. Argument is in bytes (i.e. 32bit register spacing = 4)
-f FILE, --logfile=FILE
Specify an alternate logfile from the default of /var/log/freeipmi/bmc-watchdog.log.
-n, --no-logging
Turns off all logging done by bmc-watchdog.
--config-file=FILE
Specify an alternate configuration file.
-W WORKAROUNDS, --workaround-flags=WORKAROUNDS
Specify workarounds to vendor compliance issues. Multiple workarounds can be specified separated by commas. A special command line
flag of "none", will indicate no workarounds (may be useful for overriding configured defaults). See WORKAROUNDS below for a list of
available workarounds.
--debug
Turn on debugging.
-?, --help
Output a help list and exit.
--usage
Output a usage message and exit.
-V, --version
Output the program version and exit.
SET OPTIONS
The following options can be used by the set command to set or clear various BMC watchdog configuration parameters.
-u INT, --timer-use=INT
Set timer use. The timer use value can be set to one of the following: 1 = BIOS FRB2, 2 = BIOS POST, 3 = OS_LOAD, 4 = SMS OS, 5 =
OEM.
-m INT, --stop-timer=INT
Set Stop Timer Flag. A flag value of 0 stops the current BMC watchdog timer. A value of 1 doesn't turn off the current watchdog
timer.
-l INT, --log=INT
Set Log Flag. A flag value of 0 turns logging on. A value of 1 turns logging off.
-a INT, --timeout-action=INT
Set timeout action. The timeout action can be set to one of the following: 0 = No action, 1 = Hard Reset, 2 = Power Down, 3 = Power
Cycle.
-p INT, --pre-timeout-interrupt=INT
Set pre-timeout interrupt. The pre timeout interrupt can be set to one of the following: 0 = None, 1 = SMI, 2 = NMI, 3 = Messaging
Interrupt.
-z SECONDS, --pre-timeout-interval=SECONDS
Set pre-timeout interval in seconds.
-F, --clear-bios-frb2
Clear BIOS FRB2 Timer Use Flag.
-P, --clear-bios-post
Clear BIOS POST Timer Use Flag.
-L, --clear-os-load
Clear OS Load Timer Use Flag.
-S, --clear-sms-os
Clear SMS/OS Timer Use Flag.
-O, --clear-oem
Clear OEM Timer Use Flag.
-i SECONDS, --initial-countdown=SECONDS
Set initial countdown in seconds.
-w, --start-after-set
Start timer after set command if timer is stopped. This is typically used when bmc-watchdog is used as a cronjob. This can be used
to automatically start the timer after it has been set the first time.
-x, --reset-after-set
Reset timer after set command if timer is running.
-j, --start-if-stopped
Don't execute set command if timer is stopped, just start timer.
-k, --reset-if-running
Don't execute set command if timer is running, just reset timer. This is typically used when bmc-watchdog is used as a cronjob. This
can be used to reset the timer after it has been initially started.
START OPTIONS
The following options can be used by the start command.
-G INT, --gratuitous-arp=INT
Suspend or don't suspend gratuitous ARPs while the BMC timer is running. A flag value of 1 suspends gratuitous ARPs. A value of 0
will not suspend gratuitous ARPs. If this option is not specified, gratuitous ARPs will not be suspended.
-A INT, --arp-response=INT
Suspend or don't suspend BMC-generated ARP responses while the BMC timer is running. A flag value of 1 suspends ARP responses. A
value of 0 will not suspend ARP responses. If this option is not specified, ARP responses will not be suspended.
DAEMON OPTIONS
The following options can be used by the daemon command to set the initial BMC watchdog configuration parameters.
-u INT, --timer-use=INT
Set timer use. The timer use value can be set to one of the following: 1 = BIOS FRB2, 2 = BIOS POST, 3 = OS_LOAD, 4 = SMS OS, 5 =
OEM.
-l INT, --log=INT
Set Log Flag. A flag value of 0 turns logging on. A value of 1 turns logging off.
-a INT, --timeout-action=INT
Set timeout action. The timeout action can be set to one of the following: 0 = No action, 1 = Hard Reset, 2 = Power Down, 3 = Power
Cycle.
-p INT, --pre-timeout-interrupt=INT
Set pre-timeout interrupt. The pre timeout interrupt can be set to one of the following: 0 = None, 1 = SMI, 2 = NMI, 3 = Messaging
Interrupt.
-z SECONDS, --pre-timeout-interval=SECONDS
Set pre-timeout interval in seconds.
-F, --clear-bios-frb2
Clear BIOS FRB2 Timer Use Flag.
-P, --clear-bios-post
Clear BIOS POST Timer Use Flag.
-L, --clear-os-load
Clear OS Load Timer Use Flag.
-S, --clear-sms-os
Clear SMS/OS Timer Use Flag.
-O, --clear-oem
Clear OEM Timer Use Flag.
-i SECONDS, --initial-countdown=SECONDS
Set initial countdown in seconds.
-G INT, --gratuitous-arp=INT
Suspend or don't suspend gratuitous ARPs while the BMC timer is running. A flag value of 1 suspends gratuitous ARPs. A value of 0
will not suspend gratuitous ARPs. If this option is not specified, gratuitous ARPs will not be suspended.
-A INT, --arp-response=INT
Suspend or don't suspend BMC-generated ARP responses while the BMC timer is running. A flag value of 1 suspends ARP responses. A
value of 0 will not suspend ARP responses. If this option is not specified, ARP responses will not be suspended.
-e, --reset-period
Time interval to wait before resetting timer. The default is 60 seconds.
ERRORS
Errors are logged to the bmc-watchdog log.
WORKAROUNDS
With so many different vendors implementing their own IPMI solutions, different vendors may implement their IPMI protocols incorrectly. The
following describes a number of workarounds currently available to handle discovered compliance issues. When possible, workarounds have
been implemented so they will be transparent to the user. However, some will require the user to specify a workaround be used via the -W
option.
The hardware listed below may only indicate the hardware that a problem was discovered on. Newer versions of hardware may fix the problems
indicated below. Similar machines from vendors may or may not exhibit the same problems. Different vendors may license their firmware from
the same IPMI firmware developer, so it may be worthwhile to try workarounds listed below even if your motherboard is not listed.
If you believe your hardware has an additional compliance issue that needs a workaround to be implemented, please contact the FreeIPMI
maintainers on <freeipmi-users@gnu.org> or <freeipmi-devel@gnu.org>.
assumeio - This workaround flag will assume inband interfaces communicate with system I/O rather than being memory-mapped. This will work
around systems that report invalid base addresses. Those hitting this issue may see "device not supported" or "could not find inband
device" errors. Issue observed on HP ProLiant DL145 G1.
spinpoll - This workaround flag will inform some inband drivers (most notably the KCS driver) to spin while polling rather than putting the
process to sleep. This may significantly improve the wall clock running time of tools because an operating system scheduler's granularity
may be much larger than the time it takes to perform a single IPMI message transaction. However, by spinning, your system may be performing
less useful work by not contexting out the tool for a more useful task.
ignorestateflag - This workaround option will ignore the BMC timer state flag (indicating if the timer is running or stopped) when running
in daemon mode. On some BMCs, the flag is broken and will never report that a BMC timer is running, even if it is. The workaround will take
notice of changes in the countdown seconds to determine if a timer is running or stopped. With this type of implementation, the reset-
period must be large enough to ensure minor fluctuations in the countdown will not affect the workaround. Due to the implementation of this
workaround, if another process stops the watchdog timer, it may be detectable. This option is confirmed to work around compliances issues
on Sun x4100, x4200, and x4500.
EXAMPLES
Setup a bmc-watchdog daemon that resets the machine after 15 minutes (900 seconds) if the OS has crashed (see default bmc-watchdog rc
script /etc/init.d/bmc-watchdog for a more complete example):
bmc-watchdog -d -u 4 -p 0 -a 1 -i 900
KNOWN ISSUES
Bmc-watchdog may fail to reset the watchdog timer if it is not scheduled properly. It is always recommended that bmc-watchdog be executed
with a high scheduling priority.
On some machines, the hardware based SMI Handler may disable a processor after a watchdog timer timeout if the timer use is set to some-
thing other than SMS/OS.
REPORTING BUGS
Report bugs to <freeipmi-users@gnu.org> or <freeipmi-devel@gnu.org>.
COPYRIGHT
Copyright (C) 2007-2012 Lawrence Livermore National Security, LLC.
Copyright (C) 2004-2007 The Regents of the University of California.
This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or (at your option) any later version.
SEE ALSO
freeipmi(7)
http://www.gnu.org/software/freeipmi/
bmc-watchdog 1.1.5 2012-06-15 bmc-watchdog(8)