EMC SAN and Drive letters
Posted on 2007-07-23
Drive letters issue:
We have several backend exchange servers in an active passive cluster.
Currently each Exchange server has 2 Mailstores, running on an EMC clariion cx300i
We have 3 Database luns running raid 5, and 3 Log luns running raid1
These are on seperate disks within the SAN.
We have just added 2 additional shelves so we can add more mailstores, as well as RMSE for making clones.
My problem is this:
We would like to add an additional 3 mailstores per exchange server, as well as add another backend server with 5 mailstores. So 14 more mailstores in total.
I have already created the luns using raid 5 on 5 disks ( 300GB disks ) for the databases.
Do i need to add additional luns for the logs? I believe i do.. This would be neneficial anyway to get some extra spindles on there..
So, now that i have the luns, and have added the luns to the existing storage group, what is next?
I read something about a 64K offset. Not sure what to do there.
How do i partition and format the drive to make it usable?
What about running out of drive letters. As we continue to expand, we will soon run out of drive letters. What and how do i do about that?
Without drive lletters, how can i map drives to the server, so that the Exchange clusters will know where the data exists.
How do i get the exchange servers to see more than 1 data drive for the exchange servers?
right now each backend exchange server can see the san by 2 drive letters. 1 for data, and one for logs.
How can i set this up so i will have a bunch of data drives for additional mailstores.,
This all comes about because EMC best practices is to have a seperate lun for each mailstore and log DB.
So if we have 30 mailtores, and there are only 26 drive letters, minus A, C, D = 23 drive letters available..