Re: Hardware for a database server

scott.marlowe wrote:
> On Wed, 10 Mar 2004, Erwin Brandstetter wrote:
>
>>Controller / Hard Discs:
>>RAID 5 with 4+ discs including a hot spare. But SCSI or SATA?
>>I am undecided on this. Until about a year ago, I would have said SCSI,
>>period. But I have read of SATA RAIDs for entry-level-servers doing
>>quite well and Linux dealing with it ever more smoothly.
>
>
> Standard IDE drives have an issue that all the ones I've tested so far,
> and presumably, most of the rest lie about fsync, and therefore are not
> guaranteed to have a coherent database on them should you lose power
> during a transaction.  If SATA drives in fact have proper fsyncing with
> write caching, then they're a great choice.  You might want to test one or
> two before commiting to a rack of them.

I won't debate the issues with standalone/internal ATA type drives...
especially with Scott... however most RAID subsystems regardless of
the drive technology used are viable options and a SATA RAID subsystem
attached via fibre/SAN which has an internal battery backed cache and
additional external UPS should not be discounted due to the overall
shortcomings of ATA.  External RAID subsystems get around the many
issues and limitations of internal controllers such as those offered
by 3ware, Adaptec and LSI.

I believe this to the point where I have recommended and we here are
purchasing a Candera system that is SATA connected via fibre and we're
a EMC-Hitachi-IBM storage partner/reseller/consulting shop.


>>Power supply:
>>Secured with UPS, auto-shutdown before power fails, so do I need my
>>RAID controller battery-backed still?
>
> Yep.  Power supplies fail, motherboards fry and take out the power rail
> every so often.  Idiots trip over power cords.  hehe.  been there, done
> that, got the TShirt.

Double ditto.


--
Greg Spiegelberg
  Sr. Product Development Engineer
  Cranel, Incorporated.
  Phone: 614.318.4314
  Fax:   614.431.8388
  Email: gspiegelberg@Cranel.com
Cranel. Technology. Integrity. Focus.