IBM 2109 Service Guide - Page 108

Table 27. POST tests (continued) Test Description CAM test Checks the CAM Port loopback test Checks all of the hardware in the switch: Frames are transmitted, looped back, and received A POST behaves differently depending on the startup method. A power cycle (power off and power on) is considered a cold startup. All other startups from a powered-on state are considered warm startups. When you use a cold startup to initiate a POST the long version of ramTest is executed. When you use a warm startup to initiate a POST a shorter version of ramTest is executed. Startup time with a POST varies depending on the startup method. If a switch is restarted with the POST disabled DIAG-POST_SKIPPED error log message is generated. Diagnostic tests If you access the switch using Telnet rather than using the front panel commands you will get more detailed responses regarding the condition of the switch. Telnet also allows you to use some commands that do not have an equivalent front panel command. Test menu The following diagnostic tests are available either from the front panel of the switch or by way of a Telnet session. v Switch offline v Switch online v Memory test v Port register test v Central memory test v CMI conn test v CAM test v Port loopback test v Cross port test v Spin silk test v SRAM data retention test v CMem data retention test v Display test v Display test (long) v Push button test See the "Diagnostic error messages" on page 122 for the actual error message descriptions and appropriate service actions. Running diagnostics from the front panel Figure 34 on page 93 shows the front panel buttons. 92 IBM SAN Fibre Channel Switch: 2109 Model S16 Installation and Service Guide