Failover Cluster w/ Compaq ML750

  • I am curious if anyone has attempted failover clustering with a compaq ml750. Compaq states failover clustering isn't supported on this model. Has anyone attempted to do failover clustering with a model that doesn't support failover clustering?

    Remember this when a developer tells you it will just be temporary. Temporary = Permanent.

  • This was removed by the editor as SPAM

  • I have not tried the failover (active/passive) clustering but am in the process of setting up active/active and have not had any problems yet. I don't really understand the appeal of failover clustering since you have half your resources on standby all the time.

    Why not load balance and then just live with the lessened performance if a node comes down?

  • I have not tried the failover (active/passive) clustering but am in the process of setting up active/active (Compaq ml 570 G2) and have not had any problems yet. I don't really understand the appeal of failover clustering since you have half your resources on standby all the time.

    Why not load balance and then just live with the lessened performance if a node comes down?

  • Along these same lines, has anyone attempted to cluster 2 boxes that were not identical? We have a need for the active/passive because of the large amount of revenue we process each day. However, as is typical, management wants to find the most cost effective way to do something, which, in this case is to buy 1 server instead of 2.

    Remember this when a developer tells you it will just be temporary. Temporary = Permanent.

  • quote:


    However, as is typical, management wants to find the most cost effective way to do something, which, in this case is to buy 1 server instead of 2.


    In my experience (which granted is limited compared to some posters) clustering is not for the weak of wallet. Better to get some redundancy in the single server and do regular backups. Managing a clustered server also takes more planning and maintenance (if you do it right) than a standalone server. I have found that we always run into trouble when we try to make the hardware fit the budget rather than the other way around.

  • quote:


    Compaq states failover clustering isn't supported on this model.


    I think Compaq elects to support SAN's with the ML750. Is this an option for you?

  • Do you have a link to support that? I talked to product info guy at compaq/hp who said that it wasn't supported...meaning hasn't been tested yet. If we can get the SAN solution w/ a reasonable cost then it may be an option. We have discussed the possibility.

    Additionally, we have discussed having 2 non-identical servers attached to a SAN. One would be production OLTP while the other was doing some other task. If Server A failed...we would bring up Server B and attach the database residing on the SAN to Server B. At first glance this seems like it would have a host of problems in itself...any thoughts on that? Obviously, it would be a manual failover.

    Remember this when a developer tells you it will just be temporary. Temporary = Permanent.

  • quote:


    Do you have a link to support that? I talked to product info guy at compaq/hp who said that it wasn't supported.


    That seems strange to me. I was under the impression they were specifically targeted for use with SAN's. Was your product info guy sales or server support?

    I'll contact my tech rep and see what I can find for you on the topic.

  • He was definitely server support. At least for the model we purchased, I'd be a little surprised if it was intended for the SAN since it has 21 internal bays. I really appreciate your efforts in my behalf.

    Remember this when a developer tells you it will just be temporary. Temporary = Permanent.

  • My experience is that I strongly recommend that you use hardware that is supported by the vendor in for SQL Server clustering.

    If you application is important enough to warrant you looking at protecting its availability with a clustered solution, then you will need to invest in appropriate equipment and then keep it maintained (this includes keeping the firmware up to date as you can get issues with incorrect firmware - I have seen it happen with disastrous results).

    If the ml750 is not supported then do not use it for a cluster.

    Clustering should work with different spec servers. You simply have to aware of the implications (performance etc) of that choice.

    Your manual failover solution may not work. Remember that the databases that you are attempting to attach will require SQL recovery to run. This is usually done when SQL Server starts. I don't know what will happen.

    You can easily test this by crashing a server (power it off) during a transaction. Restart the server by do not start SQL Server. Copy the database files to another server and attempt to attach them. If this works, this solution may well be an option.

    Cheers

    Stephen

  • Well I checked with my support contact today and here is what I said and his response:

    Q: Do you know if can use a SAN with a couple of ML750's? Are they

    supported?

    A: Yes these servers do support SAN solutions. It all comes down to what type of solution you are looking for. EX: EMA12000, RA8000. Will you be going through a fibre switch or an MDR, etc.

    If you need more details on these products let me know and I can have one of the engineer's that support these to e-mail you.

Viewing 13 posts - 1 through 12 (of 12 total)

You must be logged in to reply to this topic. Login to reply