Mysterious disk activity with 3ware controller?

Question

I recently moved one of my servers into the same room I sit in and noticed something strange. Each morning for an hour or more there is a huge burst of disk activity. I am running a 3ware 9750-4i RAID controller. Here is a screen dump of the controller status.

3ware utility output

The interesting bit is there is no activity showing on the server, this is a dev machine running ubuntu that is idle most of the time. Is this something that the controller is doing on its own? Some sort of daily maintenance?

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score 1 · Accepted Answer · answered Mar 12 '21 at 17:05

1

That's called disk scrubbing, media patrol, patrol read, and various other names. The RAID controller regularly read checks your arrays, so potential read errors are recognized and repaired early on.

You wouldn't want to stumble onto a hard read error while rebuilding after a drive failure, would you?

answered Mar 12 '21 at 17:05

Zac67

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Is it scheduled daily? Can I change the time? I see nothing about it in the docs. – John Mar 12 '21 at 17:27
I dunno 3ware controllers, but usually you can schedule this. [...] Possibly this helps: https://www.thomas-krenn.com/redx/tools/mb_download.php/mid.x656656334b3066483159513d/User_Guide_3Ware_9750_CLIGuide_10.0codeset.pdf – Zac67 Mar 12 '21 at 17:41
tw_cli /cx del selftest=1 – John Mar 12 '21 at 18:15
tw_cli /cx add selftest=Sun:12 – John Mar 12 '21 at 18:16
Yes, once a week is quite sufficient. – Zac67 Mar 12 '21 at 20:20

Mysterious disk activity with 3ware controller?

1 Answers1