Application Parallel read/write in common SAN volume
 

Dear Experts,

Greetings !!!

I've 2 HP DL380 G6 server with Redhat Enterprise Linux Advance Edition 5.5 x64 intalled (both the nodes having Fiber HBA cards and connected with SAN switches). I've assigned 5 common storage LUNs to both these servers on GFS2 filesystem and their mount points are /oradata, /data1, /index, /redo and /arch as requested by our DB & Application expert in our organization. I've setup 2 node Active / Passive cluster using Redhat cluster suite. Set the priority 1 to node 1 and 2 to node 2 in failover domain. The same volume and virtual ip ( or can say cluster ip for applications) will be available at one node a time. In case of failure of node 1, the cluster resources will switchover to node 2 and all the san volumes will be shifted and mounted on node2. As soon as the node 1 start working and get on the cluster resources are shifted back to node 1. This setup is tested and working fine.

Now, few things I want to explain about the role of both servers and my requirement what I want to to do.

Both servers having oracle 10g R2 and an application running on both servers. We're using GFS2 filesystem over CLVM.

1. How can the Oracle DB services will start automatically by cluster service on the server that will own the cluster resources, what I'll do to make sure that the DB service should be shutdown properly before the cluster resources get shifted to another node ?

2. I've add/assigned another 500 GB shared SAN volume to both the nodes, my purpose was to keep mounted the volume on both the servers at all the time for application files. I need to configure this volume in this way that the application on the both nodes can read/write in this volume parallely. But I also want to make sure that it should be available/accessible to another node in case any node among both will go down. Can I achieve the same in same Active / Passive cluster setup ?

3. In the reference to question no 2, Is there any way to setup the volume for parallel read/write for application in both node without cluster. I also want to add one more thing that we're having cisco based H/W load balancer through which we used to balance and forward multiple parallel read/write requests from clients (for this we're having another pair of application servers.


Thanks. Pls revert with your kind suggestions.

Arunabh

If both these systems are just for an Oracle database, then the best thing you can do is to contact your paid-for Oracle support (since you're paying for support from both Oracle and RedHat, for your Redhat Enterprise Linux), and use Oracle RAC instead.
http://www.oracle.com/technetwork/da...iew/index.html

Simultaneous mounting of the same disk(s), parallel read-writes, etc., are handled, and it makes database scaling much easier. Again, using Oracle and RHEL, you are in a supported configuration, and should be paying for support from both companies, so using what you're paying for will get you much quicker (and better) answers. They'll be able to analyze your configuration and give you detailed advice

Thanks TB0NE for the reply,

Sorry for the delayed reply.

Yes, U'r right that I can take support from Oracle. But I just wanted to do it at my level first then I'll go for support.

I want to clear few things that We're having 2 scenarios.

1. we're not going to use Oracle RAC. We've configured OS level clustering in Active / Passive mode. I want to keep start the Oracle DB services automatically on Primary node while it will keep stopped in secondary node. when the cluster services will shift from Primary to Secondary server, it should start the DB services on the other node, but before shifting to other node the DB services should stopped properly on the Primary node (in case the primary node having some network issue or like that).

2. We've also hosted an Application on both the nodes, which we want to run simultaneously on both the nodes. For that also, I've assigned a common storage volume to both the hosts. I wanted this volume to be keep mounted on both the nodes at a time, so that both the nodes can Read / write simultaneously. For that should I configure this volume in cluster configuration, or separately mount it on both the nodes by /etc/fstab file. What filesystem should I use so that there will be no parallel read/write issue will arise.

Kindly tell me how (i mean brief procedure) can I achieve this ?

Regds

Arunabh

Spell out your words..it's "your", not "u'r". Using the support you paid for is not only a good idea, it's the best and quickest way for you to learn. Asking the people who WROTE the software how it best works, will give you the best ways to do things.
Ok..again, if you've configured clustering correctly, that's how this will all work, since that's the purpose of the active/passive clustering. And again, if the two systems are ONLY Oracle database systems, NOT using RAC is a bad idea. RAC is much more capable of keeping a DB up and running no matter what.
You don't. There are experimental file systems that will allow two systems to mount the same drive in read/write at the same time, but it's not a good idea, for very obvious reasons. Oracle RAC uses its own file system and management to avoid doing bad things. Again, you are PAYING FOR SUPPORT from RHEL and Oracle...calling them is the best choice for you.