Problem Installing 11.2.0 on RHEL 7 64 Bit
Cause

The security limits requirements were not set according the recommended values

The message
[client(15674)]CRS-10001:CRS-6021: No msg for has:crs-6021 [n][65536]
makes think about the value recommended for oracle hard nofile 65536 in /etc/security/limits.conf

Then these messages makes think that probably the other parameters in /etc/security/limits.conf were not set
[client(15669)]CRS-10001:CRS-6021: No msg for has:crs-6021 [l][unlimited]
[client(15672)]CRS-10001:CRS-6021: No msg for has:crs-6021 [c][unlimited]

Solution

Using root user make sure that /etc/security/limits.conf are set as follows
oracle soft nproc 2047
oracle hard nproc 16384
oracle soft nofile 1024
oracle hard nofile 65536
oracle soft stack 10240