Best compromise Raid-levels

[Oskarsson Mikael]

Hi

A friend an and I disagree about an Exchange 2003 RAID-configuration.

Facts: A HP Proliant DL 380 with 6 x 300 GB Disks, and 4 GB RAM, Windows
2003 Std. and Exchange 2003 Ent.
Totaly 3500 mailboxes, about 400-500 at the same time.
20 GB + 40 GB Private store.
100 GB in public Store ( E-mail archive).

I want to have one RAID1 (2 disks) for OS+Pagefile+Log-files+
Exchange-program.
And a RAID5 (4 disks) to Edb/Stm-files.

My friend want to have one RAID0+1 (6 disks)

I know about that is best to have.
OS on one Raid 1.
Pagefile on one Raid 1.
Log-files on one Raid 1.
Edb/Stm-files on one RAID5.

Have I or my friend the best compromise?

Regards Mikael

[Jim Schwartz]

While in theory your friend is correct about performance in RAID0+1 being
faster that RAID 5 due to the write penalty imposed by RAID 5 you are
correct in splitting out your log files from your database files.

Optimally you would want to move the log files to a separate set of drives
than your OS, but you can get away with it in smaller environments. You may
also be able to get away with creating 3 RAID 1 volumes and separate out
the logs from the OS. You don't list the speed of the drives but you can
calculate that 2 15k disks in a RAID 1 could handle approximately 260 ops
per second.

You can use the formula in the link to see if that would handle what you
need.
http://blogs.msdn.com/exchange/archi...03/251743.aspx


"Oskarsson Mikael" <mo-konsult@swipnet.se> wrote in message
news:e80S65O%23EHA.3124@TK2MSFTNGP11.phx.gbl...

Hi

A friend an and I disagree about an Exchange 2003 RAID-configuration.

Facts: A HP Proliant DL 380 with 6 x 300 GB Disks, and 4 GB RAM, Windows
2003 Std. and Exchange 2003 Ent.
Totaly 3500 mailboxes, about 400-500 at the same time.
20 GB + 40 GB Private store.
100 GB in public Store ( E-mail archive).

I want to have one RAID1 (2 disks) for OS+Pagefile+Log-files+
Exchange-program.
And a RAID5 (4 disks) to Edb/Stm-files.

My friend want to have one RAID0+1 (6 disks)

I know about that is best to have.
OS on one Raid 1.
Pagefile on one Raid 1.
Log-files on one Raid 1.
Edb/Stm-files on one RAID5.

Have I or my friend the best compromise?

Regards Mikael

[Andy David - Exchange MVP]

My concern is the size of those disks. With 300 GB drives ( which are
generally 10K), you could see some performance issues - even in a
small environment. I would consider sep controller cards for the logs
and store. Lab testing is crucial in this regard. Unfortunately, I
have witnessed first hand the performance problems with the larger
drives on a single controller.
My $.02.




On Thu, 13 Jan 2005 02:05:51 GMT, "Jim Schwartz"
<shamusnc@nfs.earthlink.net> wrote:

While in theory your friend is correct about performance in RAID0+1 being
faster that RAID 5 due to the write penalty imposed by RAID 5 you are
correct in splitting out your log files from your database files.

Optimally you would want to move the log files to a separate set of drives
than your OS, but you can get away with it in smaller environments. You may
also be able to get away with creating 3 RAID 1 volumes and separate out
the logs from the OS. You don't list the speed of the drives but you can
calculate that 2 15k disks in a RAID 1 could handle approximately 260 ops
per second.

You can use the formula in the link to see if that would handle what you
need.
http://blogs.msdn.com/exchange/archi...03/251743.aspx


"Oskarsson Mikael" <mo-konsult@swipnet.se> wrote in message
news:e80S65O%23EHA.3124@TK2MSFTNGP11.phx.gbl...
Hi

A friend an and I disagree about an Exchange 2003 RAID-configuration.

Facts: A HP Proliant DL 380 with 6 x 300 GB Disks, and 4 GB RAM, Windows
2003 Std. and Exchange 2003 Ent.
Totaly 3500 mailboxes, about 400-500 at the same time.
20 GB + 40 GB Private store.
100 GB in public Store ( E-mail archive).

I want to have one RAID1 (2 disks) for OS+Pagefile+Log-files+
Exchange-program.
And a RAID5 (4 disks) to Edb/Stm-files.

My friend want to have one RAID0+1 (6 disks)

I know about that is best to have.
OS on one Raid 1.
Pagefile on one Raid 1.
Log-files on one Raid 1.
Edb/Stm-files on one RAID5.

Have I or my friend the best compromise?

Regards Mikael