SQL Server Performance Forum – Threads Archive
Help buying new serversI am new to the forums (and the industry in general), and am in need of much help. I am being asked to purchase some servers and storage for a high availability SQL cluster. The databases are projected to consume 100GB within the next 12-24 months. My boss is pushing for the use of dual Dell blades (1955s) attached with iSCSI to the NAS (1gb). From what I have been reading this fills me with fear and trepidation. Below is what I am proposing, and I want to know if it works, and is a better solution.<br /><br />Servers:<br />Dell 2950s<br />- Dual 5130 Xeons.<br />- 8GB RAM<br />- 4 harddrives in RAID 10 for OS and SQL binaries<br />- Separate PERC4e/DC to attach to two external 220 Powervaults<br /><br />Powervaults<br />1. Data<br />- 9 146GB harddrives<br />- 1 Hot spare<br />- 8 in RAID 10<br /><br />2. Logs and backup<br />- 9 146GB harddrives<br />- 1 Hot spare<br />- 8 in RAID 10 (or 6 in RAID 10 for backups and 2 in RAID 1 for logs)<br /><br />Can two powervaults attach to the same cluster? Is this better than a NAS/Blade server solution? Please help the new guy. <img src=’/community/emoticons/emotion-1.gif’ alt=’‘ />
Look at Joe Chang’s thread recommending hardware configs. NO blades, many small disks in direct-attached storage seems to be a theme <img src=’/community/emoticons/emotion-1.gif’ alt=’‘ />.
Check: http://www.sql-server-performance.com/forum/topic.asp?TOPIC_ID=15002 Luis Martin
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Thank you for the response! I have read over Joe’s thread, and I tried to base this off of his recommendation. There are three questions that I don’t know that answers to that are going to come up in discussions over the two solutions. 1. I don’t know much about clustering so I am curious how/if clusters work with two powervaults? It would seem strange to me if they didn’t, but I can’t find any documentation stating one way or another. 2. How to best configure the Log/backup powervault (8xRAID 10 or 2xRAID 1 and 6xRAID 10)? 3. How much performance difference is there between iSCSI (1gb) and DAS (dual channel SCSI)?
I would recommend SAS over SCSI, as SAS has nearly no bandwidth limitations the SCSI and SAS architectures do allow for a cluster solution
it used to be that the external SCSI chassis had the dual ports for SAN but i think all the vendors may have removed cluster support from their direct-attach storage lines, forcing you to buy grossly over-priced SAN solutions with marginal random IO performance and absolutely horrible sequential performance, almost guaranteed to cause you performance problems bug your vendor on whether they still support clustering on the direct-attach
tell them you don’t care if they recommend SAN, that’s just because they get fat margins on that
We have contracts with Dell so they will be a vendor regardless of what we choose. I looked at their brochure, and their SAS chassis (MD1000) does not list clustering as being supported; the SCSI chassis (220s) does. I will discuss this with the rep and hopefully he has more insight. What about cluster support for multiple powervaults?
well good for dell, but do ask on SAS
there is no reason you cannot have multiple powervaults in a cluster, just don’t daisy chain them
Thank you for your help. I will make sure that I ask Dell about SAS.