what is the paid version of pacemaker
 

- what is the paid version of pacemaker ? like incase of centos, the redhat is paid version.

What makes you think that there is a "paid" version of this open source cluster utility?

I means to say paid support where there is a SLA for providing support and fixing any problem is a defined time. unlike only forum/community support

For that you must look for one of the distributions that offers support that happens to include that utility. A quick look at the project page tree turns up a few. Of those Red Hat Enterprise Linux (RHEL), Ubuntu, and SUSE 11 are clearly commercial support distributions. Support MAY be available for others, but that is unclear. I would stick with RHEL, Ubuntu, or SUSE commercial offerings if support is critical
.

Great / Thanks
I checked below details at http://clusterlabs.org/quickstart-redhat.html under RHEL 7 > Install section

Pacemaker ships as part of the Red Hat High Availability Add-on. The easiest way to try it out on RHEL is to install it from the Scientific Linux or CentOS repositories. (now its clear for pacemaker that paid support is available in redhat distro)

But I thing I came to know that thru only pacemaker one cant make HA for any application. There is a need to use CoroSync with Pacemaker as well. Right ? (Now one more query, does CoroSync paid support is also available, like for pacemaker the redhat distro does)

Are you planning someone else's idea of a cluster, or will you build your own?

I built my own using openvz, heartbeat, DRDB, and some scripts. Someone else came along and documented a slightly more elegant setup using that technique, and their page is still up on the internet. If you build your own, you might make an error but you will have a clear understanding of how each part works. (I would not use DRDB these days, although it has improved since then there are better cluster storage solutions.)

If you are going to build one using the tools available from Red Hat, then I would look for documentation on the RHEL way to "do it" as that keeps you in a supported configuration.

I am not planning for someone else idea. Actually what I understood from clusterlabs.org that pacemaker detect fault when a resource get faulted/failed and Corosync sync the status of resources within cluster nodes. OR the CoroSync works as a heartbeat between cluster nodes to sync resources state.

(The above is my understanding, please clarify if I am wrong )

Due to the above understanding I want to make an application HA with the help of Pacemaker+CoroSync and asking to make sure myself the a paid support should also be available for both products i.e., Pacemaker+CoroSync.

It looks to me as if RHEL7 is the way to go then. Both pieces are available for RHEL7 and the support from Red Hat is excellent.

Dear wpeckham: Do you have any web link which can clarify that Pacemaker+CoroSync = Redhat Cluster Suite ?

Some pages that might help you:
https://bigthinkingapplied.com/creat...d-hatcentos-7/
https://irvingpop.github.io/blog/201...g-experiments/
There are more at the RHEL pages.

Thanks wpeckham for sharing excellent weblinks. Now my query is fulfilled.