HP Integrity rx1600 HP Management Base Installation and User's Guide for Linux - Page 12

All IPMI commands use a command/response message protocol with a requestor and a responder. In most cases on HP hardware using HP software, programs running under Linux are the requestor, and the system's BMC is the responder. The BMC hardware is exposed through a system interface, as described in the IPMI specification. This channel requires a device driver and device file to exchange commands and responses. The HP Management Base installation loads the Open IPMI driver modules and sets up the character device files /dev/ipmi/0 and /dev/ipmi0. These files are familiar to the Linux Open IPMI community (such as ipmitool). By default, hpbmc uses these files to access the local BMC. The SELprint directive is implemented in a manner similar to the following conversation: hpbmc Send "Get BMC Capabilities" Send "Get SEL Capabilities" While more SEL entries Send "Get SEL entry nnnn" Decode and print entry nnnn BMC Respond "there is an SDR, an SEL, ..." Respond "there are xxxx entries" Respond with entry nnnn Another task done during HP Management Base installation is caching of the Sensor Data Record Repository (SDRR). IPMI is intended to be self-describing and the SDRR holds the material list for the system (along with sensors). Software can construct a coherent view of the entire system starting from this material list. The SDRR is thus crucial to the completion of most hpbmc directives. Not only is the SDRR a large list, but the IPMI interface is a relatively slow channel. It can take over twenty seconds to read the SDRR on some Integrity servers. Fortunately, the SDRR is a static collection on HP Integrity servers and can easily be cached to a disk file. This caching is done during HP Management Base installation, and hpbmc reads this cache by default. The -d path option changes the path to the BMC. The HPBMC_DEVICE environment variable can be set for the same purpose. Specifying an alternate Open IPMI device file is of interest only to IPMI utility developers and is usually not done in practice. HP Management Base utilities also support the Remote Management Control Protocol (RMCP), or IPMI over LAN. This protocol works against any BMC (or IPMI controller) that uses RMCP. An RMCP exchange always requires a host target (DNS name or IP address), and it optionally uses a password and user name. The path argument then takes the following form: [[user:]password]@hostname Either use the -d option or set HPBMC_DEVICE. Here are some things to remember: • Early entry-level HP Integrity servers might not have an MP card. • Early entry-level MP card firmware does not support RMCP. The MP firmware must be upgraded to at least E.03.15 for RMCP support. The MP card is then known as the Integrity iLO Card because it is similar in functionality to the HP ProLiant iLO cards. • On entry-level Integrity iLO, RMCP access is turned OFF by default. It is enabled through the command-line interface of the MP card using the SA command. • The IPMI password on all HP Integrity servers is unset (or null) by default. • On midrange and high-end systems the RMCP password can be set through the MP card command-line interface. Entry-level systems support only RMCP password changes over RMCP; see the RMCP passwd directive of hpbmc. 12 Using HP Management Base Utilities