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Active / Passive Cluster Storage Solutions

We are looking to deploy an a/p cluster in the near future to consolidate some aging database servers into a centraly supported and maintained server group. None of these apps are huge, but we want the failover protaction of the a/p cluster. We are planning on sql 2000 configuration as the buglist on 2005 seems daunting to us. The problem I’m having is I’m getting pushback from directors to use our campus NAS solution for storage space. I know NAS isn’t a ‘recommended’ solution, but it is supported for sql 2000 under specific conditions. Is NAS even possible in an a/p configuration? I can’t find any documentation that clearly states either way. I’ve pushed back consistently that I don’t recommend using NAS, however top level management is convenced other enterprises are doing it (however he rattled off enterprises all using oracle). I’ve spent the better part of a day perousing KB articles, and have nothing defenative. I can’t find a white paper describing it, etc. Any opinions, and especially refference materials would be greatly appreciated. Trey
Description of support for network database files in SQL Server
http://support.microsoft.com/default.aspx?scid=kb;en-us;304261 SQL Server 2000 I/O Configuration in a SAN/NAS Environment
http://www.sql-server-performance.com/ew_san.asp
Hi Hope this link might be userful
http://support.microsoft.com/default.aspx?scid=kb;en-us;888374 Thanks & Regards
Ashwin Reddy
SQL Server DBA

Hi pygar Here is the link which tells that not to go for NAS. Hope this might be useful
http://www.adminlife.com/247reference/msgs/25/125351.aspx Thanks & Regards
Ashwin Reddy
SQL Server DBA

Hi there I know that MS support NAS for a single SQL server, I don’t think that NAS is supported for a cluster config. The first requirement for a cluster config is that the entire cluster hardware must be on the WSC. The MS site appears to not work right nowhttp://www.microsoft.com/windows/catalog/server/ but I’m farily certain you won’t find any NAS based clusters there… People who use a NAS for redundancy generally have a cold-standby server which is turned on when the primary server fails, but this is not always good enough for high availability systems Cheers
Twan
Thanks for the article links, one or two of these I had not seen.
The pushback I’m getting now is to use an ISCSI device to connect to the network storage. Innitial investigation seems to indicate running failover cluster on windows 2003 might support this configuration. Does anyone have any data on this, performance info, etc? Pygar
Hi ya, MS do say they support ithttp://support.microsoft.com/?id=833770 having said that, I’m always wary of adding additional components… If you are pushed to iSCSI, then I’d say
– make sure that you get full Gb connectivity, 100Mb only gives you around 10MB/s which in my opinion is just not fast enough)
– have dual redundant links
– use two NICs in each server and two NICs in the NAS with two Gb switches in between srv1
– to switch1 – to NAS
– to switch2 – to NAS srv2
– to switch1 – to NAS
– to switch2 – to NAS Be careful! I have had it before where it was thought that the iSCSI connection was traversing its own link only to find that on the NAS box both the main network and the iSCSI network were advertised as being iSCSI endpoints and the server chose to use the main network for the iSCSI traffic (a backup server in our case) Cheers
Twan
Thanks Twan! Here is a glance at what I’m thinking… 1. I plan to use ISCI TOE cards to offload the tcp processing.
2. I plan to use 1gig adapters, and have them pass thru a seperate network switch and interface on the NAS.
3. I plan to use not only redundant TOE cards, but I plan to have 2 sets. The first set will connect to the log volume, and the second set to the data volume. My fealing is seperating that traffic out will increase my I/O bandwidth to the nas thru the interfaces. Thoughts?
Hi ya,<br /><br />this is getting beyond my realm of knowledge… <img src=’/community/emoticons/emotion-5.gif’ alt=’;-)’ /><br /><br />but I think that the first thing to check is that on the NAS you can bind a volume to particular interfaces, or whether on the NAS you can only bind the iSCSI protocol itself to a set of interfaces, with all NAS volumes using that same shared pipe?<br /><br />Gb full duplex ought to be fast enough even if you do have to share the pipe though, but if you can afford additional pipes (and can configure it on the NAS) then go for it <img src=’/community/emoticons/emotion-5.gif’ alt=’;-)’ /> )<br /><br />Cheers<br />Twan<br /><br />PS if you do get all of this set up, then it would make a great article showing pitfalls and successes, and some performance measures (which I’m assuming you’ll want to do before you put this solution live) <img src=’/community/emoticons/emotion-5.gif’ alt=’;-)’ /><br /><br />
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