RHEL 5 installation and DM multipath

[techux]

Hi guys.

We have a  proliant dl-58o server and a p2o00 DAS storage with SAS. (dual controller). I am a little confused about DM Multipath.

The idea is to install rh locally and use a volumen of the P2o000   "/var"  (we have 2 volumen of same size in the storage)

When installing RH, does it by default configure DM Mutipath? 

from each controller on p200o is a cable to each port on the SAS HBA (2 connections total)

in the installer/partition section RH detect the local disk cciss and /dev/sda and /dev/sdb

there I dont know if RH detect both volumes of the storage, or if only see 1 volume 2 times because it has 2 conenction(in the sas HBA) to the storage.

if DM Mutipath is no configured by default because I am just installing, what should I do?

1- leave only one conection to the SAS HBA, install linux, then connect the other mini-sas cable and configure dm Multipath.

2-does it really worth having 2 connection to the storage? I mean, in case one controller in the storage fail, will linux use the other path without issue?

is there any other way or steps to install RH in this case?

I read redhat is no supoorting the HPDMmultpath4.41 anymore, and now we should use the native DM multipath of Redhat, am I right?