Oracle grid infrastructure bug on Linux redhat 4 reported in SR 3-2845758491 to oracle support

While I was testing to install oracle RAC on REDhat 4 I found that following error which cause the installation to get aborted:

ACFS & ADVM is not supported on redhat4

Also according to the oracle certification matrix The RAC 11G release 2  is certified on Redhat release 4 and the ACFS and ADVM is not supported .

I reported it as a bug according to the SR #3-2845758491

Note :this issue must not appear on Redhat 5 as the ACFS & ADVM is supported on it.

Stalled or Hanged Grid 11GR2 installation at 65% - Performing Remote Operations

In case the process of performing remote operations hangs while installing Rac then check your firewall and disable it using service iptables stop.
if the installation continues to work it is fine if it is not then deinstall and install again.
The process that is responsable for transporting is ractrans.
you can check it using command:
lsof -i:
sshd       3131  root    3u  IPv6   9635       TCP rac2.localdomain:ssh->192.168.0.1:savant (ESTABLISHED)
sshd       3131  root    7u  IPv4   9676       TCP localhost.localdomain:x11-ssh-offset (LISTEN)
sshd       3131  root    8u  IPv6   9677       TCP [::1]:x11-ssh-offset (LISTEN)
ractrans  18253  grid    0u  IPv4 100913       TCP rac2.localdomain:44281->rac1.localdomain:42729 (ESTABLISHED)
ractrans  18253  grid    3u  IPv4 100912       TCP *:44281 (LISTEN)