Serviceguard Clustering versus WebLogic Clustering for Web Applications

[Shivkumar]

Dear Sirs,

We run WebLogic 7.1's clustering feature for our web applications. I am thinking to recommend MC Serviceguard for High Available solution in addition to WebLogic Clustering.

Someone has raised questions what are advantages of MCSG clustering in addition to WebLogic clustering.

Can anyone suggest advantages ?

Regards,
Shiv

[Chan 007 · Accepted solution]

Hi Shiv,

Weblogic Cluster - Normally goes as N+1 setup. Which would be used for load balancing and failover.

Cluster supports only the following software services e.g. servlet/HTTP etc.

If the weblogic server fails automatically starts the instance on the next server.

As you have many servers running the instance you don't need a MCSG.

As Weblogic services are not interupter during such failures SG is not needed.

Chan

[Arunvijai_4]

Hi Shiv,

Weblogic clustering is application level clustering where as two or more instances are coupled together to provide load balancing, failover, etc.. whereas, Serviceguard is system level clustering where you share resources of OS.

-Arun

[Sameer_Nirmal]

Hi,

MCSG is High Availabilty cluster software which provides HA at host level for clustered resources. The HA is achieved by providing redundancy and failover of the cluster resources at host level. The clustered resources ranges from a network card,application failure ( mind these application doesn't have their own capability to failover) etc to complete host failure. It does provide application monitoring through scripting to provide application failover to another host.

Weblogic Clustering is application level clustering where you have multiple instances of Weblogic Server program running simulatenously on same or different machines. So if you are running these instances on differnt machines, you are achieving application redundancy at host level and at the same time you get scalability and better application performance.

Refer the this link for Weblogic Clustering
http://e-docs.bea.com/wls/docs70/cluster/overview.html#1003768

Thus if the application is spanned across multiple hosts and it provides redundancy among its instances, then MCSG is not required.

[Arunvijai_4]

Hi Shiv,

I think, you can configure Weblogic Clustering in MCSG environment since it will provide greater failover, load balancing in a dedicated and distributed env.

FYI : http://e-docs.bea.com/wls/docs81/cluster/overview.html

-Arun

[Devender Khatana]

Hi,

These are two different protections provided by application clustering and hardware clustring.

Application clustering will help you to protect against application crashes/shutdowns etc. whereas MC service guard alongwith these will also take care of some hardware failures in addition to these.

Suppose for instance, you had a local lan failed, then your application will not be able to do anything except stopping that instance and continuing to use the other one, whereas in MC service guard you will have local lan switch over to standby.

Another use will be in using one server for maintenance purposes with applications running on other.

HTH,
Devender