nut-debian/docs/man/upsmon.conf.txt
2022-07-10 09:23:45 +02:00

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UPSMON.CONF(5)
==============
NAME
----
upsmon.conf - Configuration for Network UPS Tools upsmon
DESCRIPTION
-----------
This file's primary job is to define the systems that linkman: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* 'seconds'::
upsmon 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 primary 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 secondary is greater than HOSTSYNC on the
primary, the primary will give up waiting for that secondary upsmon
to disconnect.
*HOSTSYNC* 'seconds'::
upsmon will wait up to this many seconds in primary mode for the secondaries
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 secondary systems are supposed to disconnect and shut
down right away. The HOSTSYNC timer keeps the primary upsmon from sitting
there forever if one of the secondaries gets stuck.
+
This value is also used to keep secondary systems from getting stuck if
the primary fails to respond in time. After a UPS becomes critical, the
secondary will wait up to HOSTSYNC seconds for the primary to set the
FSD flag. If that timer expires, the secondary upsmon will assume that the
primary (or communications path to it) is broken and will shut down anyway.
+
This keeps the secondaries from shutting down during a short-lived status
change to "OB LB" and back that the secondaries see but the primary 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 linkman: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 linkman: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
the `upsd` server system's linkman:upsd.users[5] file.
If your username is "observer" and your password is "abcd", the MONITOR
line might look like this (likely on a remote secondary system):
+MONITOR myups@bigserver 1 observer abcd secondary+
Meanwhile, the `upsd.users` on `bigserver` would look like this:
[observer]
password = abcd
upsmon secondary
[upswired]
password = blah
upsmon primary
And the copy of upsmon on that bigserver would run with the primary
configuration:
+MONITOR myups@bigserver 1 upswired blah primary+
The 'type' refers to the relationship with linkman:upsd[8]. It can
be either "primary" or "secondary". See linkman:upsmon[8] for more
information on the meaning of these modes. The mode you pick here
also goes in the `upsd.users` file, as seen in the example above.
*NOCOMMWARNTIME* 'seconds'::
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 linkman: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.
NOTIFYMSG ONLINE "UPS %s is getting line power"
NOTIFYMSG ONBATT "Someone pulled the plug on %s"
+
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.
NOTIFYMSG NOCOMM "Someone stole UPS %s"
+
Possible values for 'type':
ONLINE;; 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 primary (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)
*NOTIFYFLAG* 'type' 'flag'[+'flag']...::
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:
+
NOTIFYFLAG ONLINE SYSLOG
NOTIFYFLAG ONBATT SYSLOG+WALL+EXEC
+
Possible values for the flags:
+
SYSLOG;; 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.
*POLLFREQ* 'seconds'::
Normally upsmon polls the linkman: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 primary 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 secondary systems, 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 config-notes.txt file in the docs subdirectory for more information.
Refer to the section:
[[UPS_shutdown]] "Configuring automatic shutdowns for low battery events",
or refer to the online version.
*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 secondary, it will do that immediately whenever the current
overall power value drops below the MINSUPPLIES value above.
+
When upsmon is a primary, it will allow any secondaries 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.:
SHUTDOWNCMD "/sbin/shutdown -h +0"
*CERTPATH* 'certificate file or database'::
When compiled with SSL support, you can enter the certificate path here.
+
With NSS:;;
Certificates are stored in a dedicated database (data split 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.
*CERTIDENT* 'certificate name' 'database password'::
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 overridden 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 overridden for host
specified with a CERTHOST directive.
*DEBUG_MIN* 'INTEGER'::
Optionally specify a minimum debug level for `upsmon` daemon, e.g. for
troubleshooting a deployment, without impacting foreground or background
running mode directly. Command-line option `-D` can only increase this
verbosity level.
+
NOTE: if the running daemon receives a `reload` command, presence of the
`DEBUG_MIN NUMBER` value in the configuration file can be used to tune
debugging verbosity in the running service daemon (it is recommended to
comment it away or set the minimum to explicit zero when done, to avoid
huge journals and I/O system abuse). Keep in mind that for this run-time
tuning, the `DEBUG_MIN` value *present* in *reloaded* configuration files
is applied instantly and overrides any previously set value, from file
or CLI options, regardless of older logging level being higher or lower
than the newly found number; a missing (or commented away) value however
does not change the previously active logging verbosity.
SEE ALSO
--------
linkman:upsmon[8], linkman:upsd[8], linkman:nutupsdrv[8].
Internet resources:
~~~~~~~~~~~~~~~~~~~
The NUT (Network UPS Tools) home page: http://www.networkupstools.org/