We do it all the time. Redhat has a few very good KB articles on how to set up iptables to support RHCS <div class="gmail_quote">On Fri, Apr 23, 2010 at 9:46 AM, Joseph L. Casale <<a href="mailto:jcasale@activenetwerx.com">jcasale@activenetwerx.com</a>> wrote: <blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">I am getting around to enabling iptables on my two node cluster and wondered how common it was to employ outbound rules along with inbound rules. I presume that locking down the in/out directions on the heartbeat interface would mandate an explicit <multicast interface> tag... So aside from the obvious requirements of the individual services running on the nodes, any other things to be aware of when doing this? Thanks! jlc -- Linux-cluster mailing list <a href="mailto:Linux-cluster@redhat.com">Linux-cluster@redhat.com</a> <a href="https://www.redhat.com/mailman/listinfo/linux-cluster" target="_blank">https://www.redhat.com/mailman/listinfo/linux-cluster</a> </blockquote></div>