<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">Hello everyone,<div><br></div><div>We have hit this problem a couple of times now on our RHEL 6.2 initiators using our FC target. We have many dm devices which should have 4 paths to each. Sometimes we see that some of the dm devices do not have the 4 paths. The underlying /dev/sd devices do exist but they are not used by the dm device. Here is what I see:</div><div><br></div><div><span class="Apple-style-span" style="line-height: 13px; "><pre style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; line-height: 1.3em; max-height: 30em; overflow-x: auto; overflow-y: auto; word-wrap: normal; "><font class="Apple-style-span" face="Helvetica">mpathbbt (3624a9370f9b69331bb3d16650001000b) dm-11 PURE,FlashArray size=500G features='0' hwhandler='0' wp=rw `-+- policy='round-robin 0' prio=1 status=active |- 1:0:1:12 sds 65:32 active ready running `- 1:0:0:12 sdae 65:224 active ready running</font></pre></span><div><br></div></div><div>However there are devices for the remaining two paths they are just not being used by multipathd:</div><div><br></div><div><span class="Apple-style-span" style="line-height: 13px; "><pre style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; line-height: 1.3em; max-height: 30em; overflow-x: auto; overflow-y: auto; word-wrap: normal; "><font class="Apple-style-span" face="Helvetica">/dev/sg18 1 0 1 12 0 /dev/sds PURE FlashArray 100 /dev/sg30 1 0 0 12 0 /dev/sdae PURE FlashArray 100 /dev/sg39 0 0 1 12 0 /dev/sdan PURE FlashArray 100 /dev/sg48 0 0 0 12 0 /dev/sdaw PURE FlashArray 100</font></pre></span><div><br></div></div><div>You can see by the LUN serial number that the devices do point to the same LUN on the array. I am including just the LUN serial number, page 0x80, in the interest of space page 0x83's NAA number also matches for the 4 devices:</div><div><br></div><div><span class="Apple-style-span" style="line-height: 13px; "><pre style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; line-height: 1.3em; max-height: 30em; overflow-x: auto; overflow-y: auto; word-wrap: normal; "><font class="Apple-style-span" face="Helvetica"><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; line-height: 13px; font: normal normal normal 12px/normal Helvetica; ">root@r13init31 ~]# sg_inq -p 0x80 /dev/sg18</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; line-height: 13px; font: normal normal normal 12px/normal Helvetica; ">VPD INQUIRY: Unit serial number page</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; line-height: 13px; font: normal normal normal 12px/normal Helvetica; ">Unit serial number: F9B69331BB3D16650001000B</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; line-height: 13px; font: normal normal normal 10px/normal Helvetica; min-height: 12px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; line-height: 13px; font: normal normal normal 12px/normal Helvetica; ">[root@r13init31 ~]# sg_inq -p 0x80 /dev/sg30</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; line-height: 13px; font: normal normal normal 12px/normal Helvetica; ">VPD INQUIRY: Unit serial number page</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; line-height: 13px; font: normal normal normal 12px/normal Helvetica; ">Unit serial number: F9B69331BB3D16650001000B</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; line-height: 13px; font: normal normal normal 12px/normal Helvetica; min-height: 14px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; line-height: 13px; font: normal normal normal 12px/normal Helvetica; ">[root@r13init31 ~]# sg_inq -p 0x80 /dev/sg39</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; line-height: 13px; font: normal normal normal 12px/normal Helvetica; ">VPD INQUIRY: Unit serial number page</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; line-height: 13px; font: normal normal normal 12px/normal Helvetica; ">Unit serial number: F9B69331BB3D16650001000B</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 12px/normal Helvetica; min-height: 14px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; line-height: 13px; font: normal normal normal 12px/normal Helvetica; ">[root@r13init31 ~]# sg_inq -p 0x80 /dev/sg48</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; line-height: 13px; font: normal normal normal 12px/normal Helvetica; ">VPD INQUIRY: Unit serial number page</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; line-height: 13px; font: normal normal normal 12px/normal Helvetica; ">Unit serial number: F9B69331BB3D16650001000B</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; line-height: 13px; font: normal normal normal 12px/normal Helvetica; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; line-height: 13px; font: normal normal normal 12px/normal Helvetica; ">I can see in the syslog that there are syslog messages about each of the devices which don't get added to the multipath device like this:</div></font></pre></span><span class="Apple-style-span" style="line-height: 13px; "><pre style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; line-height: 1.3em; max-height: 30em; overflow-x: auto; overflow-y: auto; word-wrap: normal; "><font class="Apple-style-span" face="Helvetica">Jun 21 09:23:50 r13init31 kernel: sd 0:0:1:12: [sdan] Attached SCSI disk Jun 21 09:23:50 r13init31 multipathd: sdan: add path (uevent) Jun 21 09:23:50 r13init31 multipathd: mpathbbt: failed in domap for addition of new path sdan</font></pre></span><div><br></div><div><div>My multipath tools version is:</div></div></div><div><div>device-mapper-multipath-libs-0.4.9-46.el6_2.2.x86_64</div><div>device-mapper-multipath-0.4.9-46.el6_2.2.x86_64</div></div><div><br></div><div>Any ideas why the paths are being rejected by domap?</div><div><br></div><div>Thanks,</div><div>Brian</div><div><br></div><div><div apple-content-edited="true"> <div>Brian Bunker</div><div><a href="mailto:brian@purestorage.com">brian@purestorage.com</a></div><div><br></div><br class="Apple-interchange-newline"> </div> <br></div></body></html>