I’ve seen youtubers and others online say that you should have a mirrored SLOG, but I didn’t get any warnings for making a striped log vdev. Can I assume I’m good to go? What are the downsides of running something like this? I’m running it on an enterprise SSD.
Its how I have run for quite some time. There is no real downside - you would need multiple failures all happening at the same time for the single SLOG to matter
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The SLOG or the L2ARC are not pool critical in the way normal VDEVs, DEDUP and Special Metadata devices are.
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The ONLY time a failed SLOG can cause data loss, is when an OS crash or power loss happens, with data in the SLOG that has not been written to Data vDevs, AND the SLOG fails after the OS crash or power loss, but before it can be flushed to Data vDevs.
Complicated I know. For certain software, (DBs or VMs), Sync writes are so critical that Mirrored SLOG is considered standard.
Under normal conditions, any graceful shutdown or reboot won’t need the SLOG because the data in RAM is flushed to Data vDevs. During normal pool operation, if a SLOG fails, no problem, the data is still in RAM, with future Sync writes going to in-pool ZIL.
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