Chris's Wiki :: blog/linux/SystemdSATAPortMultiplierProblem Commentshttps://utcc.utoronto.ca/~cks/space/blog/linux/SystemdSATAPortMultiplierProblem?atomcommentsDWiki2017-06-25T21:12:13ZRecent comments in Chris's Wiki :: blog/linux/SystemdSATAPortMultiplierProblem.By Chris Siebenmann on /blog/linux/SystemdSATAPortMultiplierProblemtag:CSpace:blog/linux/SystemdSATAPortMultiplierProblem:b5f5560d6600930afdbd263d176c441765c1c008Chris Siebenmann<div class="wikitext"><p>The solution we wound up using is a custom script that's run by hand
to mount everything. It finds the right disk order by introspecting the
system to determine the scsiN:N:N:N naming for each device and sorting
that into order. This works for us because our only systems with ESATA
enclosures are Amanda backup servers and they always take hand attention
to verify that we have the right 'tapes' loaded after a disk shuffle,
but it's obviously not a good solution for a machine where you care
about it coming up without manual attention.</p>
<p>(I believe we also had problems where the ESATA enclosures took a bit
of time to settle after a reboot and have all disks seen, so we couldn't
reliably (re)mount disks at boot time anyways.)</p>
</div>2017-06-25T21:12:13ZBy Matthias on /blog/linux/SystemdSATAPortMultiplierProblemtag:CSpace:blog/linux/SystemdSATAPortMultiplierProblem:cdbd54767b08f8be253ad9549050568e90074981Matthias<div class="wikitext"><p>Thanks for the information - I'm running a fresh Ubuntu 16.04 installation and have run into the same issue. </p>
<p>In the meantime: how did you deal with the problem? Any hint for a custom udev rule?</p>
<p>Regards,
Matthias</p>
</div>2017-06-25T06:47:14ZBy Anon on /blog/linux/SystemdSATAPortMultiplierProblemtag:CSpace:blog/linux/SystemdSATAPortMultiplierProblem:8a992c848e0d3a1b32489bbd7ff6be6cf282c452Anon<div class="wikitext"><p>As the previous comment suggested it looks like the upstream issue cks filed ( <a href="https://github.com/systemd/systemd/issues/3943">https://github.com/systemd/systemd/issues/3943</a> ) is going to stall because the systemd devs don't want to maintain the disk helpers any more. I guess the only hope is to write custom udev rules. Too bad - the issue was filed with a useful data...</p>
</div>2016-08-21T05:25:15ZBy Twirrim on /blog/linux/SystemdSATAPortMultiplierProblemtag:CSpace:blog/linux/SystemdSATAPortMultiplierProblem:6f40962a0f784f4a43d55b07d6e46a012d874060Twirrim<div class="wikitext"><p>Looks like it has already been reported upstream earlier this year:
<a href="https://github.com/systemd/systemd/pull/2500#issuecomment-178071901">https://github.com/systemd/systemd/pull/2500#issuecomment-178071901</a></p>
<p>Doesn't sound like a fix is coming.</p>
</div>2016-08-12T18:15:27ZBy Chris Siebenmann on /blog/linux/SystemdSATAPortMultiplierProblemtag:CSpace:blog/linux/SystemdSATAPortMultiplierProblem:4f32c7c36e1642cf261362be0eb2741e6c1f5df3Chris Siebenmann<div class="wikitext"><p>The problem in our situation is that UUIDs (and serial numbers and so on)
are tied to the disks, not the slots in the enclosures, and we rotate
disks in and out of the enclosures in the course of making backups.
The actual disks are self-identifying to the overall backup system once
mounted (<a href="http://www.amanda.org/">Amanda</a> puts labels on them), but we
have to mount them by enclosure slot in order to get that far.</p>
<p>(As a side thing, we also need to be able to identify which old disks to
pull out by slot instead of by UUID or serial number, because otherwise
pulling some old disks would involve either carefully keeping track of
what disk ID was in what slot or temporarily pulling several in order to
find the one you wanted. Well, okay, the real answer is that we'd write
scripts to determine the mappings, but if we're going to write scripts
we might as well write udev rules instead.)</p>
</div>2016-08-11T13:58:43ZFrom 54.240.193.1 on /blog/linux/SystemdSATAPortMultiplierProblemtag:CSpace:blog/linux/SystemdSATAPortMultiplierProblem:a2c47f24a0990fb56c00e14c22175d86200f00eeFrom 54.240.193.1<div class="wikitext"><p>I had thought device by id was always a little buggy. </p>
<p>What about UUID?
<a href="https://help.ubuntu.com/community/UsingUUID">https://help.ubuntu.com/community/UsingUUID</a></p>
<p>I had always understood this to be the solution of SCSI or SATA or other bus systems detecting disks in the incorrect order</p>
</div>2016-08-11T13:03:55Z