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Rebuilding SQL server – options for data and logs

IF poss please move to the hardware forum – posting error [<img src=’/community/emoticons/emotion-5.gif’ alt=’;)‘ />]<br /><br />My client has a pile of Dell 2550 servers with 5 discs configured with a RAID 1 and RAID 5 array.<br /><br />One of the 4 servers is running 4 instances of SQL – the others are DC, Exchange, File and backup servers.<br /><br />Currently they have the OS on the RAID 1 and SQL data, logs etc on the RAID5.<br /><br />Clearly this is not a recommended setup but in light of the fact we cant add any more discs (only 5 slots) and an external array is probably out of the question, I need another solution.<br /><br />One idea was this:<br /><br />1. Put the OS and databases on the RAID5 array and logs on the RAID1<br /><br />2. Create two RAID1 arrays, put the OS on a single disc (no raid) and the database and logs on the two RAID 1 arrays<br /><br />3. Keep the config as it is and log-ship to another server – a dedicated pc in the server room even!<br /><br />The first two seem full of holes and unsatisfactory – the third is a work-around and better than the first two…<br /><br />If I can then an external array is the way to go – they are not too expensive these days…<br /><br />Any other options?<br /><br />(moved from General DBA section)
If you can’t buy more disks, I’d put the OS and Logs on the Raid 1 mirror and put the data on Raid 5. If poss buy 2 more disks so you can add another mirror and keep the logs separate from the OS. Tom Pullen
DBA, Oxfam GB
I agree with Thomas on this. That 3 disk RAID 5 array will never perform well though. The company needs to choke up some money if they really need a big performance increase on disk IO. MeanOldDBA
[email protected] When life gives you a lemon, fire the DBA.
I have found a bunch of 36GB SCSI discs – 6 in total. I am thinking of proposing that they buy an external disc enclosure, stick the databases on that and move two of the discs from the server into the enclosure for RAID-1 logs. Seem reasonable enough? The server is running 4 instances of SQL at the moment – I might try and cut that down a bit by moving development to a pc as they don’t really need it. To me this seems a good solution giving space to grow by adding more discs.
Just makes sure you have a good enclosure. It sounds like a good solution though without spending a lot of money. Most enclosures will support 14 or 15 drices. Getting rid of instances will always help because you won’t have disk contention with the multipls tempdb databases, etc and you have more memory resources free. MeanOldDBA
[email protected] When life gives you a lemon, fire the DBA.