upsd.conf - Configuration for Network UPS Tools upsd

upsd uses this file to control access to the server and set some other miscellaneous configuration values. This file contains details on access controls, so keep it secure. Ideally, only the upsd process should be able to read it.

ACL name netblock

Define an Access Control List (ACL) called name that contains the network netblock. The netblock can be either the old style, such as this for a traditional "class C":

ACL mynet 192.168.50.0/255.255.255.0

Or, you can use newstyle "CIDR format":

ACL mynet 192.168.50.0/24

To just list one host, it would look like one of these:

ACL mybox 192.168.50.1/255.255.255.255

ACL mybox 192.168.50.1/32

ACLs are used whenever you need to refer to a network or host, such as in ACCEPT/REJECT definitions (below) and with "allowfrom" in upsd.users(5).

"ACCEPT

ACCEPT let clients on the hosts or networks defined by aclname connect to upsd. You may specify multiple ACL names on the ACCEPT line, and you may have multiple ACCEPT lines.

ACCEPT localhost mybox

ACCEPT otherbox

"REJECT

Like ACCEPT, but it denies access instead. upsd will close the connection without reading any data from the network.

Note: you should still use firewall rules if your system provides them. That provides another level of coverage.

REJECT badbox

REJECT all

Here is an example configuration to show some of what is possible.

"bigserver" has a UPS attached to a serial port. It runs the driver, upsd, and upsmon in master mode. This definition is also referenced with an "allowfrom" in upsd.users(8).

"workstation" draws from the same UPS as "bigserver", but has to monitor it over the network. It runs upsmon in slave mode. It is also referenced with an "allowfrom" in upsd.users(8).

"webserver" doesn't get power from this UPS at all, but it runs the CGI programs so it can make nice status displays.

An abuser's host is explicitly denied.

Everything else is rejected.

	ACL bigserver 10.20.30.1/32
	ACL workstation 10.20.30.2/32
	ACL webserver 10.20.30.3/32
	ACL abuser 192.168.255.128/32
	ACL all 0.0.0.0/0

ACCEPT bigserver workstation webserver REJECT abuser REJECT all

ACCEPT and REJECT directives are checked in the order they occur in this file. The first ACL which matches a client causes the action to be taken. If you need to ACCEPT one host and REJECT the rest of a network, first list the host, then list the network on a line below it.

ACCEPT goodhost

REJECT badnet

Any IP address which does not match one of your directives will default to REJECT. This is intended to keep your system safe if you forget to put "REJECT all" at the bottom.

If you really want the whole world to have access to upsd, you can do "ACCEPT all", but that is not recommended.

MAXAGE seconds

upsd usually allows a driver to stop responding for up to 15 seconds before declaring the data "stale". If your driver takes a very long time to process updates but is otherwise operational, you can use MAXAGE to make upsd wait longer.

Most users should leave this at the default value.

STATEPATH path

Tell upsd to look for the driver state sockets in path rather than the default that was compiled into the program.

upsd(8), nutupsdrv(8), upsd.users(5)

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