<html><head><meta http-equiv="Content-Type" content="text/html charset=us-ascii"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;">going out on a limb...<div><br><div><div>On Apr 22, 2014, at 2:02 PM, Saso Kiselkov <<a href="mailto:skiselkov.ml@gmail.com">skiselkov.ml@gmail.com</a>> wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite">On 4/22/14, 10:31 PM, Schweiss, Chip wrote:<br><blockquote type="cite"><br>On Tue, Apr 22, 2014 at 3:17 PM, Saso Kiselkov <<a href="mailto:skiselkov.ml@gmail.com">skiselkov.ml@gmail.com</a><br><<a href="mailto:skiselkov.ml@gmail.com">mailto:skiselkov.ml@gmail.com</a>>> wrote:<br><br><br> I know, but if I understand it correctly, I need to not only disable a<br> particular path, I need to disable mpath support entirely to get<br> sg_write_buffer to talk to mpt_sas directly, instead of going through<br> the scsi_vhci glob in the middle (which, presumably, is what's causing<br> this problem). If I'm misunderstanding this, please do set me straight.<br><br> Cheers,<br> --<br> Saso<br><br><br>Actually no. Disabling a physical path works too. That is how I<br>stumbled upon the MP issue. I plugged one of my paths into a second<br>server to attempt using Linux to flash the firmware. When the flash<br>started working from the primary server, I never loaded Linux in the<br>second server.<br><br>I think the problem is actually in the disk accepting firmware via<br>multipath not so much the OS. The OS throws the error when a message<br>down a second path gets rejected by the drive. <br></blockquote></blockquote><div><br></div><div>This is plausible. The default multipath policy of round-robin means that it will</div><div>chop up such big transfers across both ports. One would think that the drives</div><div>would treat this as one server, multiple queues, but my recent experience with</div><div>drive firmware bugs reaffirms the old adage: never assume anything.</div><br><blockquote type="cite"><br>Still no luck, though it's possible I'm doing it wrong:<br><br># mpathadm disable path -l /dev/rdsk/c9t5000C500578F774Bd0s2 \<br> -i w5b8ca3a0e5029c00 -t w5000c500578f774a<br><br># mpathadm show lu /dev/rdsk/c9t5000C500578F774Bd0s2<br>Logical Unit: /dev/rdsk/c9t5000C500578F774Bd0s2<br> mpath-support: libmpscsi_vhci.so<br> Vendor: SEAGATE<br> Product: ST2000NM0023<br> Revision: 0003<br> Name Type: unknown type<br> Name: 5000c500578f774b<br> Asymmetric: no<br> Current Load Balance: round-robin<br> Logical Unit Group ID: NA<br> Auto Failback: on<br> Auto Probing: NA<br><br> Paths:<br> Initiator Port Name: w5b8ca3a0e5029c00<br> Target Port Name: w5000c500578f774a<br> Override Path: NA<br> Path State: OK<br> Disabled: yes<br><br> Initiator Port Name: w5b8ca3a0e5029c00<br> Target Port Name: w5000c500578f7749<br> Override Path: NA<br> Path State: OK<br> Disabled: no<br></blockquote><div><br></div><div>The other lesson I've learned recently is that some drive firmware is </div><div>keyed to look at one port over the other for certain operations :-(</div><div>While I have no knowledge or suspicion of it in this specific case, you might</div><div>try switching ports.</div><br><blockquote type="cite"><br> Target Ports:<br> Name: w5000c500578f774a<br> Relative ID: 0<br><br> Name: w5000c500578f7749<br> Relative ID: 0<br><br># sg_write_buffer -v --in=MegalodonES3-SAS-STD-0004.LOD \<br> --length=1625600 --mode=5 /dev/rdsk/c9t5000C500578F774Bd0<br> Write buffer cmd: 3b 05 00 00 00 00 18 ce 00 00<br>ioctl(USCSICMD) failed with os_err (errno) = 22<br>write buffer: pass through os error: Invalid argument<br>Write buffer failed res=-1<br><br>The situation is the same regardless of which path I disable. At the<br>point of the sg_write_buffer, I also get a single SCSI error logged by<br>"iostat -E", so it's clear there's something wrong going on on the SCSI<br>bus. I suspect it might have something to do with what you mentioned,<br>but I'm just no SCSI guru to figure this out.<br></blockquote><div><br></div><div>fmdump -eV shows SCSI error reports in detail. </div><div> -- richard </div></div><br><div apple-content-edited="true">
<div style="color: rgb(0, 0, 0); font-family: Helvetica; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><span class="Apple-style-span" style="border-collapse: separate; border-spacing: 0px;"><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; border-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; "><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; border-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; "><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; border-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; "><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">--</div><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><br></div><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><a href="mailto:Richard.Elling@RichardElling.com">Richard.Elling@RichardElling.com</a><br>+1-760-896-4422<br><br><br></div></span></div></span></div></span></div></span></div>
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