[Gllug] DD Ext3 Move

Rich Walker rw at shadow.org.uk
Thu Feb 9 23:51:45 UTC 2006


Nix <nix at esperi.org.uk> writes:

> On Thu, 09 Feb 2006, Rich Walker announced authoritatively:
>> Nix <nix at esperi.org.uk> writes:
>> 
>> [snip LVM stuff]
>> 
>> Are you doing LVM-on-"RAID>0" or just relying on detecting potential
>> failure early enough?
>
> LVM-on-RAID-5 --- at least that's what I'll be setting up now these

splendid.

> hardware problems appear resolved (really weird hardware problems,
> too; turn on ECC L2 cache RAM, and get intermittent single-bit errors
> under high load: turn it off, and the errors go away. ECC shouldn't
> introduce errors, should it?)

Might be - turn on ECC, *detect* single-bit errors. turn off ECC,
*don't* detect single-bit errors.

I.e. - replace machine time.

You did the "thousand kernel compiles" test?

>
>> (a) I've got half-a-dozen disks set up as 5-in-RAID-5 + boot disk, and
>>     I wouldn't put the data on RAID-0 or LVM-without-RAID
>
> It's only recently that I've had more than two disks in one machine, or
> more than one disk of any vaguely similar size. Now I've got 1x50Gb
> and 2x73Gb in one machine, it's time for 50Gbx3 RAID-5... :)

Now, if you could just wean yourself off SCSI/FC and onto PATA/SATA, you
could put 6 or 8 200GB disks in instead for the same money, and probably
manage the same speed, as well as having a hot spare for the day
everything goes south...


> (There will be some un-RAIDed storage there, as well, probably for swap
> and things like MP3s which I can just re-rip if a disk dies. But
> everything of significance is going under the RAID-5 hammer, including
> the root filesystem.)

I'm still trying to work out whether to try RAID-ing swap
partitions. 'Cos, at the moment, if a RAID disk with a non-RAID swap
partition on it dies, I lose (potentially) all running processes as well...

>
>> (b) but my backups are incremental and not of the 350GB of "stuff", just
>>     the 100GB of "good stuff".
>
> My backups are semi-incremental (level 0 on CD-R, incremental on CD-RW
> until I run out of disks, then incremental on CD-R against the most
> recent CD-R backup), but of *everything*. I'm a paranoid madman :)

>From time to time I run multicd to generate DVD's. That's always fun -
it takes *forever* to do my maildir alone...


cheers Rich.

-- 
rich walker         |  Shadow Robot Company | rw at shadow.org.uk
technical director     251 Liverpool Road   |
need a Hand?           London  N1 1LX       | +UK 20 7700 2487
www.shadow.org.uk/products/newhand.shtml
-- 
Gllug mailing list  -  Gllug at gllug.org.uk
http://lists.gllug.org.uk/mailman/listinfo/gllug




More information about the GLLUG mailing list