Re: [exim] RAID level for mailstore

Tom Brown wrote:
> W B Hacker wrote:
>> Graeme Fowler wrote:
>>
*snip*
>
> thanks all for the responses and also for an enlightening thread -
>
> I have 6 spindles available to me and i _could_ also do RAID1+0 but the
> sacrifice on space is not worth it for me - The disks are 10k SCSI (this
> is a slightly aged GL 380) and its a 'propper' hardware controller. I
> have been in this game for ~10 years and apart from a SAMBA server i'd
> personally never use SATA for server grade kit.

I never even used ATA at *home* for more years than enough.

But modern HDD are outgrown before they wear out.

> I like SAS but alas this
> is a 'home' machine and so SCSI it is.
>

> Thanks for the comments i think i'll go for 3 RAID1's for binary, scan
> and store
>
> cheers all!
>

Take it one step further...

- Use an 'unseen' router to archive.

- Use the identical dirtree as the 'working' (POP/IMAP accessable)
mailstore.

Except at the top level mount-point.

Place that on a different RAID1 array from the working mailstore.

as in:

working:

/dev/ar1s1d /mail/$domain/$local_part/Maildir

archive:

/dev/ar2s1d /rkyv/$domain/$local_part/Maildir

Presto - near-real-time separate-array incremental backup. Outbound as
well if you want it.

IMAP folders, deletions, et al not replicated. But all the traffic can be.

If running FreeBSD, GMIRROR can do that to off-box drives as well as
local, and for either/both the working and archive. GigE or better
recommended. Other OS'en have similar tools.

HTH,

Bill