Would a RAIDz2 pool's integrity be (entirely) contingent on the persistence of a SLOG ..?

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TrumanHW

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Sep 16, 2018
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I think I had a defective SLOG, but, but also thought that a pool is only at a SLOGs 'mercy' while it's temporarily passing the data through ..?
Excluding those times, the pools persistence isn't contingent on the device when no data's been written to it, no?

Removed the SLOG to inspect it (assuming it was bad) and the pool no longer mounts with or without the SLOG now.
I think it's all backed up & none is too important from it anyway, but would rather not lose even unimportant crap.

Anyway, the pool's not only not mounted, but even searching to try mounting the RAIDz2 pool (w/o the SLOG) TrueNAS sees none to mount.

as in... No zPool to mount.png
 
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TrumanHW

Active Member
Sep 16, 2018
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Good news, it's already fixed ... (and my recollection that ... provided a slog isn't writing something -- it's removal shouldn't corrupt the poo).

The command that fixed it:

zpool import -m [pool name]

And -- apparently -- the ZIL did work.
...nex problem; can't stupid-replicate the zvol. lol. EVERYTHING is like invading normandy.
 
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TrumanHW

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Sep 16, 2018
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Don't understand the comment about replicating a zvol?
Ah, I have 2 TrueNAS computers and I'm transferring the data of 1 unit to the other.

For whatever reason I was consistently doing something wrong.
I think the SSH was validated ...
I could browse the other pool via the LAN to select the folder I wanted to copy (replicate).
But every time I created & started a task, I'd get some error (w. a massive dump of info I couldn't decode).

I've watched people configure things on YouTube but didn't quite follow...

If you know of instructions you think I should review I can do that ...
If you really want to see the report of why it failed I think I have it (if you really want it). lol. :)
 

ericloewe

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Apr 24, 2017
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SLOGs are not critical, but losing SLOG will lose whatever is on it that doesn't exist in the pool proper, yet - at most some 8 seconds of data.
 

dswartz

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Jul 14, 2011
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Also, if slog device fails and you reboot, it won't import the pool (have to do so manually with, IIRC '-m' flag...)