Smart Array P400 mix & match SAS

[Mikezie_1]

Hi all,

I have DL380 G5 with P400 256mb cache with 2HDD with part #418367-B21 in a raid1, I need to convert it to raid5 adding 2 more HDD with part # 507125-B21.

Q1 - is there any issue or performance impact? if I mix 2 different SAS HDD I know the 418367-b21 is 3G model and the 507125-b21 is 6G model.

Q2 - if I upgrade my raid controller to 512mb with bbwc, what impact will it do on the system?

thanks.

[Trygve Henriksen · Accepted solution]

You may find this document useful...

http://bizsupport1.austin.hp.com/bc/docs/support/SupportManual/c01460725/c01460725.pdf

3G and 6G is theoretical max transmission speeds(3Gigabit/S - 6Gigabit/6), with an emphasis on theoretical.
Any RAID with dissimmilar drives will slow to the speed of the slowest HDD in it. (Or thereabout)
As long as you don't mix SAS and SATA drives in the same ARRAY, you're usually OK, though.

What impact on the system a RAID memory upgrade has depends on where your bottlenecks are, and what the server is used for.
Does that controller have battery-backed Cache RAM?
(Battery-backed RAM means it's 'safe', for a given value of safe, to switch on 'Delayed Write', and that gies a nice, big boost)