This resource agent works supports various of APCs upper-end UPSes - including the Back-UPS Pro, Smart-UPS and Matrix-UPS. This resource agent has been tested with the 900XLI, the SmartUPS 700 and the SmartUPS 1000. This includes both older and newer versions of some of the firmware.
This agent was heavily based on the Network UPS Tools (NUT) project. The protocol which these UPSes is described on a NUT page. These UPSes require a special serial cable, which normally comes with the UPS, and is described on another NUT page.
Note that you have to cross-connect the UPSes for this to work out. Node A has to be cabled to node B's UPS, and node B has to be cabled to control node A's UPS.
ttydev - the tty device name which you have the UPS for the machine in hostlist plugged into
hostlist - the name of the host being controlled by the UPS connected to ttydev
These UPSes are often available with new batteries at reasonable prices through e-Bay. SmartUPS, BackUPS Pro Matrix UPS
American Power Conversion web site.