Raid 1 & 10 vs Raid 10

[freedomit]

So we are putting together a new Server for a LOB application, the Server has a IIS/.net front end and SQL database. The Server is going to be a HPE DL180, Xeon E5-2620v4, 32GB DDR4 and have 6 x 300GB 15k 12G SAS drives with a 2GB FBWC. Windows Server 2016 is going to be installed on the bare metal.

The question is regarding RAID configuration...would you create a RAID 1 (2 disks) for the OS and a RAID 10 (4 disks) for the database or one large RAID 10 (6 disks) with a C/D partition? Normally i would put the OS and database on different spindles/volumes but RAID 10 gets quicker with more disks so i think in theory one large RAID 10 should be faster.

Thoughts?

 

[YeOldeStonecat]

For just 1x server....I'd be fine with a single RAID 10 since you have 6 drives. Kinda...6 of 1 half a dozen of the other thing.
For hypervisors I definitely like to split things...since there's a lot more load. But since you're doing 6x drives...single server...negligible.

I would do a C, D, and E partition if it's a heavier SQL database...toss the logs over on a 3rd volume.

Geeze..then you got the question...."Should I do 3x pairs of RAID1?" Hmmm....

 

[freedomit]

Geeze..then you got the question...."Should I do 3x pairs of RAID1?" Hmmm....

I didnt even think about that...so many options to choose from!!!

I'm leaning towards one big raid 10, my thinking is that most of the time the OS C drive will have low I/O so its potential speed going to waste.

 

[YeOldeStonecat]

Yeah with that much memory, paging of the swapfile on C will be minimal....and you can control the install of all the SQL Server files to the D drive.

 

[Matthew Bradley]

Not to play devils advocate here but have you priced 15K SAS drives in the event one of those needs replacing (I'll save you the trouble - they're expensive as hell)? Considering how they're being phased out of production anyhow, by the time you actually need to replace one they'll be even MORE expensive. Especially for SQL, enterprise grade SSD's will give you FAR more IOPS. For what its worth, I'd go with 3 RAID 1 SSD's.

 

[freedomit]

Not to play devils advocate here but have you priced 15K SAS drives in the event one of those needs replacing (I'll save you the trouble - they're expensive as hell)? Considering how they're being phased out of production anyhow, by the time you actually need to replace one they'll be even MORE expensive. Especially for SQL, enterprise grade SSD's will give you FAR more IOPS. For what its worth, I'd go with 3 RAID 1 SSD's.

We are paying £160 per drive which I didn't think was that expensive? Anyway we have purchased a HPE 5 year 24x7 4 hour warranty so if one fails we get a replacement for free within 4 hours.

I look at prices for SSD's but I thought they were expensive. Maybe in a couple of years when costs come down we can drop a pair in and move the data base to them.

 

[YeOldeStonecat]

How "big" of a load are we talking about here? Could be just an 800 meg or 4 gig SQL database....and we're sweating out the details thinking it'll be some 60 gig database.

 

[freedomit]

Database is 8gb and is used by around 50 users

 

[NviGate Systems]

For what I use RAID for, I just use RAID 1, it possibly is the easiest RAID to walk away from in the event of disaster. But a word of warning, some cheap RAID controllers don't always play fair, and some RAID 1 drives are mirrored, but always show up as empty drives if removed and plugged into another system. I assume the firmware in the RAID chip tracks reads and writes. So it's not really reliable.

I always look for something that works well and gives me an escape route should there be a 57 car pileup or if the RAID switches allegiance and tries to assassinate my data in an opera house. You never know what rogue chips will do!

Kidding aside, always make sure whatever RAID you go with, you test and ensure you have a recovery plan, because as awesome as RAID is, it's not bullet proof.

 

[fencepost]

I just set someone up with a new VM server configured with a (currently) 10-drive RAID10 plus a couple of hot spares. 2.5" 10K drives.

One thing I did spec on the server is to go ahead and set it up for up to 32 2.5" drives - switching to that added I think less than $200 to the cost of the server, and having all those empty drive bays makes for a lot more configuration and expansion options that really are difficult to add later on. Part of what's going to be on there is 2+ TB of medical imaging data that needs to be accessible fairly quickly but would be stupid to put on SSD.