[systemd-devel] Need help with a systemd/mdadm interaction.

[Ian Pilcher]

On 11/12/2013 11:49 AM, Colin Guthrie wrote:
> It seems to me that doing this automatically is a bad idea if someone
> simply forgot to plug in a drive... or, and this has happened to me
> (tho' I stress not *by* me!), removes the wrong drive. I guess I'm in
> two minds on this one as I can see the usefulness of just coping and
> carrying on but the prospect of a multi-day resync with modern large
> disks for a simple mistake isn't too nice either!

It can be hard to get user input during early boot on a headless server.

;-)

I think that there are actually several related issues here:

1) A way to express per-array policy, maybe in mdadm.conf.

   - Wait XX seconds for all devices to show up, then start degraded

   - Wait for some other sort of event before starting degraded

   - Never start degraded

   - Start as soon as possible, even if degraded (not sure what the use
     case for this one would be)

2) Implementation of those policies -- udev rules, dracut, systemd,
   mdadm?

3) Sensible "hardcoded" defaults

4) Support for creating appropriate policies in tools like anaconda

Only after 1 and 2 are in place can 3 and 4 be meaningfully addressed.

-- 
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Ian Pilcher                                         arequipeno at gmail.com
           Sent from the cloud -- where it's already tomorrow
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