<!doctype html public "-//W3C//DTD HTML 4.0//EN"> <html> <head> <title>Apcupsd's Support for SNMP UPSes</title> <meta name="Author" content="Riccardo Facchetti"> <link rel=stylesheet href="apcupsd-styles.css" type="text/css"> </head> <body> <h1>Apcupsd's Support for SNMP UPSes</h1> <h2>General</h2> Apcupsd version 3.10.0 or later provides direct support for SNMP UPSes. To run <b>apcupsd</b> with an SNMP UPS, you need the following things: <ul> <li>An SNMP UPS, for example a Web/SNMP card installed into the SmartSlot. </li> <li>Apcupsd version 3.10.0 or higher</li> <li><a href="http://www.netsnmp.org/">NETSNMP</a> library (previously known as ucd-snmp) installed</li></ul> <p> <h2>Connecting an SNMP UPS</h2> The Simple Network Management Protocol provides an interface to connect to remote devices through the network. <b>apcupsd</b> is now capable of using the SNMP interface of an SNMP-enabled UPS to communicate with an UPS. Currently <b>apcupsd</b> supports only APC's PowerNet MIB. To enable the SNMP support it is enough to configure the correct device in your apcupsd.conf configuration file. The directive needed for this configuration is: <pre> DEVICE 192.168.100.2:161:APC:private </pre> where the directive is made by four parts: <ul> <li>IP address of the remote UPS</li> <li>Remote SNMP port</li> <li>Kind of remote SNMP agent, currently can only be "APC" for APC's powernet MIB</li> <li>The read-write community string, usually it is "private" for read-write access.</li></ul> <p> <h2>Building and Installing apcupsd</h2> Follow the instructions in the <a href="install.html">Installation Chapter</a> of this manual, being sure to include the following options (in addition to any others you need) on the <b>./configure</b> line: <pre> ./configure \ --with-serial-dev=<your-SNMP-device> \ --with-upstype=snmp \ --with-upscable=smart \ --enable-pthreads \ --enable-snmp </pre> <h2>SNMP Specific Information</h2> The SNMP connection gives less information compared to a serial smart cable. This is not a problem as the most useful information is given, together with a number of secondary parameters that are informative enough to run safely your UPS. <h2>Known Problems</h2> <h3>Power Off (killpower) of SNMP UPS needs special handling</h3> <p></p>Currently (as of 3.10.0) the code to power off the UPS needs special configuration. The killpower command for SNMP UPSes can not be issued during shutdown as tipically at some time during shutdown operations the network stack is stopped. To overcome this problem it is needed to modify the /etc/rc.d/apcupsd system control script to tell <b>apcupsd</b> to issue the power down command (killpower) to the UPS immediately before apcupsd initiates the system shutdown. For this reason it is paramount to set your UPS grace time to a value greater than 120 seconds to allow for clean shutdown operations before the UPS removes the power from its plugs. To enable correct shutdown operation during powerdown do the following: <ul> <li>Connect to your Web/SNMP card using your favorite web browser, go to the UPS configuration menu and change the "Shutdown Delay" parameter to 180 seconds or more, depending on how much time your system shutdown requires to umount all the filesystems.</li> <li>Change /etc/rc.d/apcupsd script adding the '--kill-on-powerfail' to the apcupsd invocation.</li> <li>Restart your <b>apcupsd</b></li></ul> <p> With this setup your UPS operations should be safe. <hr> <a href="usb.html" target="_self"><img src="back.gif" border=0 alt="Back"></a> <a href="kernel_config.html" target="_self"><img src="next.gif" border=0 alt="Next"></a> <a href="index.html"><img src="home.gif" border=0 alt="Home"></a> </body> </html>
