Network UPS Tools - Quick Start for Debian ------------------------------------------ Anyway, here are the quick start instructions for using nut: These Quick Start instructions are useful for a UPS connected to a single machine. For a UPS connected to multiple machines, additional steps must be taken, as outlined at the end of this file, including the notice regarding SECURITY CONSIDERATIONS. (I) Upgrading ============= In case of upgrading, follow instructions given in: /usr/share/doc/nut/UPGRADING Note that service(s) (driver(s), upsd, upsmon) are not restarted upon upgrade, to avoid service disruption. You have to manually do it. (II) Installation ================= Configuration files are located in /etc/nut/ In order to tune NUT configuration according to your needs, follow the below information, along with the one provided inside these files. (1) /etc/nut/nut.conf (see 'man 5 nut.conf' for more information) Edit /etc/nut/nut.conf and modify the "MODE" variable according to your configuration. You can also fine tune the daemons options through UPSD_OPTIONS and UPSMON_OPTIONS. The steps 2 to 5 are only required if you use a "standalone" or "netserver" MODE. If you are running in "netclient" MODE, jump directly to section 6. (2) /etc/nut/ups.conf (see 'man 5 ups.conf' for more information) Edit /etc/nut/ups.conf and add something like: [myups] driver = usbhid-ups port = auto Use the appropriate driver for your UPS and select the correct port. To select the driver, take a look at the UPS compatibility list: /usr/share/nut/driver.list If you have more than one UPS, add as many entries as needed. If you wish to test manually whether your configuration of ups.conf is correct, you may invoke upsdrvctl by hand (as root): /sbin/upsdrvctl start [myups] /sbin/upsdrvctl stop [myups] Ensure that the permissions of ups.conf do not permit the world to read it. It should already be thus, but the following command accomplishes this: chown root:nut /etc/nut/ups.conf chmod 640 /etc/nut/ups.conf (3) device port permissions The nut user need to be able to access the device port both for reading and writing. For serial devices, there are two possibilities: a) You can add the nut user to the dialout group. The following command accomplishes this: addgroup nut dialout This is not done by default for security reason on Debian, but is applied on Ubuntu. b) Another solution, for system supporting udev, is to create a file, For example /etc/udev/rules.d/92-nut-serialups.rules. It will be used after /lib/udev/rules.d/91-permissions.rules, and contains something like: KERNEL=="ttyS1", GROUP="nut" where 'ttyS1' has to be replaced by the exact name of your serial port. For USB devices, permissions are automatically set by the /lib/udev/rules.d/52-nut-usbups.rules udev rules file. (4) /etc/nut/upsd.conf (see 'man 5 upsd.conf' for more information) the default /etc/nut/upsd.conf is fine for a "standalone" configuration. If you are in "netserver" MODE, you will have to modify the LISTEN option to something suitable. Ensure that the permissions of upsd.conf do not permit the world to read it. It should already be thus, but the following command accomplishes this: chown root:nut /etc/nut/upsd.conf chmod 640 /etc/nut/upsd.conf (5) /etc/nut/upsd.users (see 'man 5 upsd.users' for more information) Edit /etc/nut/upsd.users and add something like the following, without the comments, in order to define a user: [monmaster] password = blah upsmon master Please use *different* usernames and passwords than you use on your system; see the note regarding SECURITY CONSIDERATIONS at the end of this file. Ensure that the permissions of upsd.users do not permit the world to read it. It should already be thus, but the following command accomplishes this: chown root:nut /etc/nut/upsd.users chmod 640 /etc/nut/upsd.users (6) /etc/nut/upsmon.conf (see 'man 5 upsmon.conf' for more information) Edit /etc/nut/upsmon.conf and add something like the following: MONITOR myups@localhost 1 monmaster blah master POWERDOWNFLAG /etc/killpower SHUTDOWNCMD "/sbin/shutdown -h +0" Ensure that the permissions of upsmon.conf do not permit the world to read it. It should already be thus, but the following commands accomplishes this: chown root:nut /etc/nut/upsmon.conf chmod 640 /etc/nut/upsmon.conf (7) /etc/default/nut This file is not used anymore. nut.conf provides all the needed features to replace this file. (8) start the daemon Invoke '/etc/init.d/nut start' to start the daemon(s). Check /var/log/syslog to ensure that upsd, appropriate drivers, and upsmon started up correctly. Additional Notes for Sharing a UPS ---------------------------------- If you have multiple machines connected to the same UPS, you will need to (a) modify the access control lists in upsd.conf on the server; (b) add additional users to upsd.users on the server; and (c) configure upsmon.conf on the clients. Please note that upsmon on a client machine and upsd on a server machine need to communicate via your network. This means that you need to ensure that all the networking equipment (hub, switch, router, etc.) between the client and the server is powered by the UPS. Otherwise, when the power goes down, the network connection between the client machine will be broken and the client will not be told to shut down. SECURITY CONSIDERATIONS ----------------------- Finally, please be aware of the following SECURITY CONSIDERATIONS: the TCP communications between the client daemon, upsmon, and the server daemon, upsd, send the username and passwords defined in upsd.users and used in upsmon.conf over the wire UNENCRYPTED. This means that somebody could sniff the username and password. A version that encrypts the connection using SSL should be available someday. Please see the documentation in /usr/share/doc/nut/docs for more information.