<html><head><meta http-equiv="Content-Type" content="text/html charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class="">We have most of our GPFS NSD storage set up as pairs of RAID boxes served by failover pairs of servers.<div class="">Most of it is FibreChannel, but the newest four boxes and servers are using dual port SAS controllers.</div><div class="">Just this week, we had one server lose one out of the paths to one of the raid boxes. Took a while</div><div class="">to realize what happened, but apparently the port2 ID changed from 51866da05cf7b001 to</div><div class="">51866da05cf7b002 on the fly, without rebooting. Port1 is still 51866da05cf7b000, which is the card ID (host_add).</div><div class=""><br class=""></div><div class="">We’re running gpfs 4.2.2.1 on RHEL7.2 on these hosts.</div><div class=""><br class=""></div><div class="">Has anyone else seen this kind of behavior? </div><div class="">First noticed these messages, 3 hours 13 minutes after boot:</div><div class=""><div style="margin: 0px; font-size: 17px; line-height: normal; font-family: Menlo;" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">Jan 10 13:15:53 storage043 kernel: megasas: Err returned from build_and_issue_cmd</span></div><div style="margin: 0px; font-size: 17px; line-height: normal; font-family: Menlo;" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">Jan 10 13:15:53 storage043 kernel: megasas: Err returned from build_and_issue_cmd</span></div><div style="margin: 0px; font-size: 17px; line-height: normal; font-family: Menlo;" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">Jan 10 13:15:53 storage043 kernel: megasas: Err returned from build_and_issue_cmd</span></div><div style="margin: 0px; font-size: 17px; line-height: normal; font-family: Menlo;" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">Jan 10 13:15:53 storage043 kernel: megasas: Err returned from build_and_issue_cmd</span></div><div style="margin: 0px; font-size: 17px; line-height: normal; font-family: Menlo;" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">Jan 10 13:15:53 storage043 kernel: megasas: Err returned from build_and_issue_cmd</span></div><div style="margin: 0px; font-size: 17px; line-height: normal; font-family: Menlo;" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">Jan 10 13:15:53 storage043 kernel: megasas: Err returned from build_and_issue_cmd</span></div><div style="margin: 0px; font-size: 17px; line-height: normal; font-family: Menlo;" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">Jan 10 13:15:53 storage043 kernel: megasas: Err returned from build_and_issue_cmd</span></div></div><div class=""><span style="font-variant-ligatures: no-common-ligatures" class=""><br class=""></span></div><div class="">The multipath daemon was sending lots of log messages like:</div><div class=""><div style="margin: 0px; font-size: 17px; line-height: normal; font-family: Menlo;" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">Jan 10 13:49:22 storage043 multipathd: mpathw: load table [0 4642340864 multipath 3 pg_init_retries 50 queue_if_no_path 1 rdac 1 1 round-robin 0 1 1 8:64 1]</span></div><div style="margin: 0px; font-size: 17px; line-height: normal; font-family: Menlo;" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">Jan 10 13:49:22 storage043 multipathd: mpathaa: load table [0 4642340864 multipath 3 pg_init_retries 50 queue_if_no_path 1 rdac 1 1 round-robin 0 1 1 8:96 1]</span></div><div style="margin: 0px; font-size: 17px; line-height: normal; font-family: Menlo;" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">Jan 10 13:49:22 storage043 multipathd: mpathx: load table [0 4642340864 multipath 3 pg_init_retries 50 queue_if_no_path 1 rdac 1 1 round-robin 0 1 1 8:128 1]</span></div></div><div class=""><span style="font-variant-ligatures: no-common-ligatures" class=""><br class=""></span></div><div class=""><span style="font-variant-ligatures: no-common-ligatures" class="">Currently worked around problem by including 00 01 and 02 for all 8 SAS cards when mapping LUN/volume to host groups.</span></div><div class=""><span style="font-variant-ligatures: no-common-ligatures" class=""><br class=""></span></div><div class=""><span style="font-variant-ligatures: no-common-ligatures" class="">Thanks,</span></div><div class=""><span style="font-variant-ligatures: no-common-ligatures" class=""> — ddj</span></div><div class=""><span style="font-variant-ligatures: no-common-ligatures" class="">Dave Johnson</span></div><div class=""><span style="font-variant-ligatures: no-common-ligatures" class="">Brown University CCV</span></div></body></html>