ha nfs replacement

[Shankar_6]

Hi,

I have 2*nodes cluster with oracle RAC using HA-NFS for writing archive logs.

HA-NFS exports the file system as part of cluster package. I have other 2*packages that starts database instance(only raw devices..no file systems) and mounts the nfs file system during startup.

I had nfs problem 2 months before where it says "nfs server is not responding" which forced us to restart all the cluster services. We had same problem recently and we have involved HP.HP asked us to run some scripts to collect the stats when there was a problem.We sent the stats and HP suggested that its a known issue and to go for PHNE_39167 to fix the problem.

I would need suggestion to get replacement of using common nfs file system..what would be the feasible options?

Attached the software installed and bdf outputs for information.

-shan

[Mel Burslan · Accepted solution]

Running an hanfs package on the same cluster that consumes that nfs share is not a very good idea. Going out on a limb here, it is a very bad idea in my opinion.

I am not sure how keen are you on writing your archive logs to an NFS mounted filesystem but my suggestion would be to use a local filesystem that is brought up as a part of your oracle cluster package. I know you are not using any filesystems but for this one, you can make an exception and create, activate and mount a filesystem.

If you will insist on using NFS, I'd suggest you to buy an external NAS appliance, like from Netapp or EMC. They are reltively cheap and since they are single purpose machines, they do their job really well.

HTH

[ManojK_1]

HI Shankar,

For Oracle RAC are u using CFS,RAW DISKS or Oracle ASM?

Using NFS for Archive Logs is not at all a good idea.

I understand from your info that you are using One DB Server as NFS server and the other as NFS client. Better Keep some other server as NFS server and make both the DB Nodes as NFS Client. It will give better parallism.

In our environment we are completely using ORACLE ASM and as per best practise i found this is the best compared to RAW Disks and NFS.

Thanks and Regards,
Manoj K

[Shankar_6]

HI,

Thanks for your reply.

We are using raw devices for oracle RAC,and file system only for archive logs.

This nfs file system gets mounted using ip that is on a clic interface.

Any other options other then netapp or oracle ASM (basically without any additional cost)..? please suggest..

-shankar

[Steven E. Protter]

Shalom,

You might find better results with NFS v4. Right now the only way to get that is to use HP-UX 11.31.

I think you are in the short term better off patching NFS as recommended by HP.

One problem with writing archive logs to an NFS share is that it goes through the network and is subject to network speed limits.

If you connected your systems to a SAN and created a shared volume group for archive logs and wrote the archive logs through the SAN, you would get much better performance.

SEP

[Mel Burslan]

>Any other options other then netapp or oracle ASM (basically without any additional cost)..? please suggest..

My main suggestion on my previous post, creating a filesystem as part of the package and to write the archive logs to this filesystem is the best way to handle this. And since you already have the serviceguard, there is no addditional cost to you other than investing some of your time to configure this. On all our clustered oracle instances (mainly consumed by SAP) we have this set up and I am yet to see any problems with this approach, whereas, NFS, even though we are not writing anything heavy and critical like database archive logs to it, is always flaky and problematic.

HTH

[Shankar_6]

Hi,

I am happy with all your suggestions.

Steven - nfs file systems are mounted using IP that are applied on clic interfaces and not using public network.

When you said shared volume group to overcome nfs, we have shared vg's used by oracle RAC but they have not got any file systems in it,only raw devices.

Can I go for shared file systems in this? or do i need to go for any product to use shared file systems ?
How good is using shared file systems here?

Any help in this is very much appreciated.

-Shan

[ManojK_1]

Hi Shankar,

If you planning for shared FileSystem then you have to buy Veritas Cluster File system and it is costly.

Thanks and Regards,
Manoj K

[Shankar_6]

Thanks for all your reply.