I am working on a project with 50 - 70 servers in the AT&T data center on University. They have either RHEL5U3 or CentOS5U3 on the systems. I have DNS configured with the normal bind 9 packages that come with CentOS5U3. My problem is when using ssh to get between the systems if i use the short name for a system it takes a long time to get to a shell prompt on the remote system. If I use the fully qualified domain name or the IP address of I use a "-4" with the short name I get to a shell prompt immediately. So to illustrate: root@adm # ssh new75 takes a LONG time to get shell prompt. Any of the following get me a shell prompt almost immediately: root@adm # ssh -4 new75 root@adm # ssh new75.wholedomain.here root@adm # ssh 10.4.5.6 (IP address of new75 system) Since the "-4" option seems to have a positive effect I have gone to each system and made sure the IPv6 kernel modules are not loaded and the network file in /etc/sysconfig/ has the following line in it: NETWORKING_IPV6=no but that made little or no difference to the problem. The lines I added to the /etc/modprobe.conf file look like this: alias net-pf-10 off alias ipv6 off I believe it some strange interaction problem between IPv6 and DNS but I do not have a clear plan on what to try next. Any suggestions? -- Steven DuChene --------------------------------------------------- PLUG-discuss mailing list - PLUG-discuss@lists.plug.phoenix.az.us To subscribe, unsubscribe, or to change your mail settings: http://lists.PLUG.phoenix.az.us/mailman/listinfo/plug-discuss