table of contents
UPSMON.CONF(5) | NUT Manual | UPSMON.CONF(5) |
NAME¶
upsmon.conf - Configuration for Network UPS Tools upsmonDESCRIPTION¶
This file’s primary job is to define the systems that upsmon(8) will monitor and to tell it how to shut down the system when necessary. It will contain passwords, so keep it secure. Ideally, only the upsmon process should be able to read it. Additionally, other optional configuration values can be set in this file.CONFIGURATION DIRECTIVES¶
DEADTIME secondsupsmon allows a UPS to go missing for this many seconds
before declaring it "dead". The default is 15 seconds.
upsmon requires a UPS to provide status information every few seconds (see
POLLFREQ and POLLFREQALERT) to keep things updated. If the status fetch fails,
the UPS is marked stale. If it stays stale for more than DEADTIME seconds, the
UPS is marked dead.
A dead UPS that was last known to be on battery is assumed to have changed to a
low battery condition. This may force a shutdown if it is providing a critical
amount of power to your system. This seems disruptive, but the alternative is
barreling ahead into oblivion and crashing when you run out of power.
Note: DEADTIME should be a multiple of POLLFREQ and POLLFREQALERT. Otherwise,
you’ll have "dead" UPSes simply because upsmon isn’t
polling them quickly enough. Rule of thumb: take the larger of the two
POLLFREQ values, and multiply by 3.
FINALDELAY seconds
When running in master mode, upsmon waits this long after
sending the NOTIFY_SHUTDOWN to warn the users. After the timer elapses, it
then runs your SHUTDOWNCMD. By default this is set to 5 seconds.
If you need to let your users do something in between those events, increase
this number. Remember, at this point your UPS battery is almost depleted, so
don’t make this too big.
Alternatively, you can set this very low so you don’t wait around when
it’s time to shut down. Some UPSes don’t give much warning for
low battery and will require a value of 0 here for a safe shutdown.
Note
If FINALDELAY on the slave is greater than HOSTSYNC on the master, the master
will give up waiting for the slave to disconnect.
HOSTSYNC seconds
upsmon will wait up to this many seconds in master mode
for the slaves to disconnect during a shutdown situation. By default, this is
15 seconds.
When a UPS goes critical (on battery + low battery, or "FSD": forced
shutdown), the slaves are supposed to disconnect and shut down right away. The
HOSTSYNC timer keeps the master upsmon from sitting there forever if one of
the slaves gets stuck.
This value is also used to keep slave systems from getting stuck if the master
fails to respond in time. After a UPS becomes critical, the slave will wait up
to HOSTSYNC seconds for the master to set the FSD flag. If that timer expires,
the slave will assume that the master is broken and will shut down anyway.
This keeps the slaves from shutting down during a short-lived status change to
"OB LB" that the slaves see but the master misses.
MINSUPPLIES num
Set the number of power supplies that must be receiving
power to keep this system running. Normal computers have just one power
supply, so the default value of 1 is acceptable.
Large/expensive server type systems usually have more, and can run with a few
missing. The HP NetServer LH4 can run with 2 out of 4, for example, so
you’d set it to 2. The idea is to keep the box running as long as
possible, right?
Obviously you have to put the redundant supplies on different UPS circuits for
this to make sense! See big-servers.txt in the docs subdirectory for more
information and ideas on how to use this feature.
Also see the section on "power values" in upsmon(8).
MONITOR system powervalue username password
type
Each UPS that you need to be monitor should have a
MONITOR line. Not all of these need supply power to the system that is running
upsmon. You may monitor other systems if you want to be able to send
notifications about status changes on them.
You must have at least one MONITOR directive in upsmon.conf.
system is a UPS identifier. It is in this form:
<upsname>[@<hostname>[:<port>]]
The default hostname is "localhost". Some examples:
•"su700@mybox" means a UPS called
"su700" on a system called "mybox". This is the normal
form.
•"fenton@bigbox:5678" is a UPS called
"fenton" on a system called "bigbox" which runs
upsd(8) on port "5678".
powervalue is an integer representing the number of power supplies that
the UPS feeds on this system. Most normal computers have one power supply, and
the UPS feeds it, so this value will be 1. You need a very large or special
system to have anything higher here.
You can set the powervalue to 0 if you want to monitor a UPS that
doesn’t actually supply power to this system. This is useful when you
want to have upsmon do notifications about status changes on a UPS without
shutting down when it goes critical.
The username and password on this line must match an entry in that
system’s upsd.users(5). If your username is
"monmaster" and your password is "blah", the MONITOR line
might look like this:
MONITOR myups@bigserver 1 monmaster blah master
Meanwhile, the upsd.users on bigserver would look like this:
[monmaster] password = blah upsmon master # (or slave)
upsmon will trigger a NOTIFY_NOCOMM after this many
seconds if it can’t reach any of the UPS entries in this configuration
file. It keeps warning you until the situation is fixed. By default this is
300 seconds.
NOTIFYCMD command
upsmon calls this to send messages when things happen.
This command is called with the full text of the message as one argument. The
environment string NOTIFYTYPE will contain the type string of whatever caused
this event to happen.
If you need to use upssched(8), then you must make it your NOTIFYCMD by
listing it here.
Note that this is only called for NOTIFY events that have EXEC set with
NOTIFYFLAG. See NOTIFYFLAG below for more details.
Making this some sort of shell script might not be a bad idea. For more
information and ideas, see docs/scheduling.txt
Remember, this command also needs to be one element in the configuration file,
so if your command has spaces, then wrap it in quotes.
NOTIFYCMD "/path/to/script --foo --bar"
This script is run in the background—that is, upsmon forks before it
calls out to start it. This means that your NOTIFYCMD may have multiple
instances running simultaneously if a lot of stuff happens all at once. Keep
this in mind when designing complicated notifiers.
NOTIFYMSG type message
upsmon comes with a set of stock messages for various
events. You can change them if you like.
Note that %s is replaced with the identifier of the UPS in question.
The message must be one element in the configuration file, so if it contains
spaces, you must wrap it in quotes.
Possible values for type:
ONLINE
NOTIFYFLAG type flag[+flag][+flag]...
NOTIFYMSG ONLINE "UPS %s is getting line power"
NOTIFYMSG ONBATT "Someone pulled the plug on %s"
NOTIFYMSG NOCOMM "Someone stole UPS %s"
UPS is back online
ONBATT
UPS is on battery
LOWBATT
UPS is on battery and has a low battery (is
critical)
FSD
UPS is being shutdown by the master (FSD = "Forced
Shutdown")
COMMOK
Communications established with the UPS
COMMBAD
Communications lost to the UPS
SHUTDOWN
The system is being shutdown
REPLBATT
The UPS battery is bad and needs to be replaced
NOCOMM
A UPS is unavailable (can’t be contacted for
monitoring)
By default, upsmon sends walls global messages to all
logged in users) via /bin/wall and writes to the syslog when things happen.
You can change this.
Examples:
Possible values for the flags:
SYSLOG
POLLFREQ seconds
NOTIFYFLAG ONLINE SYSLOG NOTIFYFLAG ONBATT SYSLOG+WALL+EXEC
Write the message to the syslog
WALL
Write the message to all users with /bin/wall
EXEC
Execute NOTIFYCMD (see above) with the message
IGNORE
Don’t do anything
If you use IGNORE, don’t use any other flags on the same line.
Normally upsmon polls the upsd(8) server every 5
seconds. If this is flooding your network with activity, you can make it
higher. You can also make it lower to get faster updates in some cases.
There are some catches. First, if you set the POLLFREQ too high, you may miss
short-lived power events entirely. You also risk triggering the DEADTIME (see
above) if you use a very large number.
Second, there is a point of diminishing returns if you set it too low. While
upsd normally has all of the data available to it instantly, most drivers only
refresh the UPS status once every 2 seconds. Polling any more than that
usually doesn’t get you the information any faster.
POLLFREQALERT seconds
This is the interval that upsmon waits between polls if
any of its UPSes are on battery. You can use this along with POLLFREQ above to
slow down polls during normal behavior, but get quicker updates when something
bad happens.
This should always be equal to or lower than the POLLFREQ value. By default it
is also set 5 seconds.
The warnings from the POLLFREQ entry about too-high and too-low values also
apply here.
POWERDOWNFLAG filename
upsmon creates this file when running in master mode when
the UPS needs to be powered off. You should check for this file in your
shutdown scripts and call upsdrvctl shutdown if it exists.
This is done to forcibly reset the slaves, so they don’t get stuck at the
"halted" stage even if the power returns during the shutdown
process. This usually does not work well on contact-closure UPSes that use the
genericups driver.
See the shutdown.txt file in the docs subdirectory for more information.
RBWARNTIME seconds
When a UPS says that it needs to have its battery
replaced, upsmon will generate a NOTIFY_REPLBATT event. By default, this
happens every 43200 seconds (12 hours).
If you need another value, set it here.
RUN_AS_USER username
upsmon normally runs the bulk of the monitoring duties
under another user ID after dropping root privileges. On most systems this
means it runs as "nobody", since that’s the default from
compile-time.
The catch is that "nobody" can’t read your upsmon.conf, since
by default it is installed so that only root can open it. This means you
won’t be able to reload the configuration file, since it will be
unavailable.
The solution is to create a new user just for upsmon, then make it run as that
user. I suggest "nutmon", but you can use anything that isn’t
already taken on your system. Just create a regular user with no special
privileges and an impossible password.
Then, tell upsmon to run as that user, and make upsmon.conf readable by it. Your
reloads will work, and your config file will stay secure.
This file should not be writable by the upsmon user, as it would be possible to
exploit a hole, change the SHUTDOWNCMD to something malicious, then wait for
upsmon to be restarted.
SHUTDOWNCMD command
upsmon runs this command when the system needs to be
brought down. If it is a slave, it will do that immediately whenever the
current overall power value drops below the MINSUPPLIES value above.
When upsmon is a master, it will allow any slaves to log out before starting the
local shutdown procedure.
Note that the command needs to be one element in the config file. If your
shutdown command includes spaces, then put it in quotes to keep it together,
i.e.:
CERTPATH certificate file or database
SHUTDOWNCMD "/sbin/shutdown -h +0"
When compiled with SSL support, you can enter the
certificate path here.
With NSS:
CERTIDENT certificate name database password
Certificates are stored in a dedicated database (splitted
in 3 files). Specify the path of the database directory.
With OpenSSL:
Directory containing CA certificates in PEM format, used
to verify the server certificate presented by the upsd server. The files each
contain one CA certificate. The files are looked up by the CA subject name
hash value, which must hence be available.
When compiled with SSL support with NSS, you can specify
the certificate name to retrieve from database to authenticate itself and the
password required to access certificate related private key.
CERTHOST hostname certificate name certverify
forcessl
When compiled with SSL support with NSS, you can specify
security directive for each server you can contact.
Each entry maps server name with the expected certificate name and flags
indicating if the server certificate is verified and if the connection must be
secure.
CERTVERIFY 0 | 1
When compiled with SSL support, make upsmon verify all
connections with certificates.
Without this, there is no guarantee that the upsd is the right host. Enabling
this greatly reduces the risk of man-in-the-middle attacks. This effectively
forces the use of SSL, so don’t use this unless all of your upsd hosts
are ready for SSL and have their certificates in order.
When compiled with NSS support of SSL, can be overriden for host specified with
a CERTHOST directive.
FORCESSL 0 | 1
When compiled with SSL, specify that a secured connection
must be used to communicate with upsd.
If you don’t use CERTVERIFY 1, then this will at least make sure
that nobody can sniff your sessions without a large effort. Setting this will
make upsmon drop connections if the remote upsd doesn’t support SSL, so
don’t use it unless all of them have it running.
When compiled with NSS support of SSL, can be overriden for host specified with
a CERTHOST directive.
SEE ALSO¶
upsmon(8), upsd(8), nutupsdrv(8).Internet resources:¶
The NUT (Network UPS Tools) home page: http://www.networkupstools.org/02/25/2014 | Network UPS Tools 2.7.1. |