IBM DS4700 and RDAC

[Wahyu Darmawan]

Hi all,

I have problem with my servers. I use two of HP Blade Servers and RHEL 4.6 installed on them, and have IBM DS4700 connected to them.
In those servers are running RHCS (Red Hat Cluster Suite) with GFS for handling Oracle Database.
Yesterday, I had missing one partition from the storage, suddenly. I called IBM and they suggested to use RDAC.
The question is, Why should use IBM RDAC for multipath in my RHEL 4, and why HP Blade + HP EVA Storage don't use any addition plugins software to keep server + storage connection?
I will appreciate For some reasons by all of you. 
Thank you.


Regards,
Wahyu