Here is what I am looking at doing...
Create 2 RAID 5 logical drives in a fully populated 3510 with 2 Global Spares.
Create 2 LUNs one for each LD.
Connect different servers to each LUN.
Each LUN will be about 1.17TB.
Should I use partitions instead? Or should I break up the LD's into more LUNs? I guess I am asking, when do you use partitions as opposed to LUNs?
Thanks!
Joe
I suppose this depends on what you want to do with the storage. There are some limitations on greater the 1 TB luns depending on the OS.You need EFI labels on greater that 1 TB devices.
Veritas 4.1 and Solaris 10 are required if you want to manage over 1 TB with Veratis. If you just want to have a filesystem, you can use ufs but find out which flavour and patch level of Solaris you can you.
Anyway, I would not use partitions and I would break the LD down through the use of LUNs. This seems to be a defacto standard in Sun for some unknown reason. Even the training says dont use partitions.
Be aware that even though you have large sizes to work with, it does not mean your host can cope with them. If you intend to put a database on the LUNs, be very careful.
Cheers
Stephen
Hi Pers,
There is nothing wrong with using LUNs, it is just that providing one large LD that are split up into multiple LUNs could have some performance and availability considerations with the database.
Eg, just say you want three LUNS, one for database files, one for redo or transaction logs (perhaps one for index files) and one for backups. If you present all three LUNS from the one LD, you are likely to have performance problems.
We just went through a problem where one of our inexperienced staff gave a TB to Oracle people and the database has got considerably slower as the data filled up. It has taken lots of effort to fix this problem.
The bigger drives on the 3510 are not necessarly good for databases. The 3510 has only 1 GB of array cache per controller (active -active so it could be viewed as 2 GB).
So just because you have the storage, don't expect it will perform like you think it will.
Another thing is that the firmware on the 3510 needs to be 4.15. If it is anything lower, having a RAID 5 with a global spare is not exactly going to give you the availability you require especially with 4.13.
The 351x series are good systems when they work but they do have major issues with availability. This has supposedly been fixed with 4.15 but they said the same thing last time they released a firmware patch. I wont use them in a seriously important system. I have learnt my lesson.
Stephen
