How to Increase the number of simultaneous/concurrent TCP connections in Red Hat Enterprise Linux 5 and 6 ?

/var/log/messages may show that number of TCP connections has been exhausted and kernel is dropping packets.

To modify the maximum allowed TCP sessions in RHEL 5 and 6, with reference to https://access.redhat.com/site/solutions/94803, here is the solution

In RHEL 5, modify the following parameter

    /proc/sys/net/ipv4/netfilter/ip_conntrack_max

In RHEL 6, modify the following parameter

     /proc/sys/net/ipv4/netfilter/ip_conntrack_max

The increase in TCP session limit will result in more core memory being used.