<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <meta content="text/html;charset=ISO-8859-1" http-equiv="Content-Type"> </head> <body bgcolor="#ffffff" text="#0050d0"> Sent: Mon Jan 10 2011 09:25:58 GMT-0700 (Mountain Standard Time) From: Matthias Saou <a class="moz-txt-link-rfc2396E" href="mailto:thias@spam.spam.spam.spam.spam.spam.spam.egg.and.spam.freshrpms.net"><thias@spam.spam.spam.spam.spam.spam.spam.egg.and.spam.freshrpms.net></a> To: <a class="moz-txt-link-abbreviated" href="mailto:rhelv6-list@redhat.com">rhelv6-list@redhat.com</a> Subject: Re: [rhelv6-list] IP load balancing <blockquote cite="mid:20110110172558.4aa76407@python3.es.aed.lan" type="cite"> <pre wrap="">Patrick H. wrote : </pre> <blockquote type="cite"> <pre wrap="">So I just started setting up a RHEL6 box for use in a load balanced cluster and have run across a problem. The way you set up a virtual IP on the back end realhost side is to add an interface alias to the loopback device (such as lo:0). Well the ifup-eth script in RHEL6 refuses to add aliases to the loopback interface. Additionally if you try to add the alias to the real ethX device instead it fails because the arping check it does finds that the IP is already running on the IPVS director. So, how is one supposed to setup a realhost now? The difference from RHEL5 is that RHEL5 doesnt check to see if youre adding an alias to the loopback device or not. Why does RHEL6 even care about that anyway? Theres nothing wrong with it... </pre> </blockquote> <pre wrap=""> I've quickly tested a simple ifcfg-lo:0 like this and it works fine for me on RHEL6 : DEVICE=lo:0 IPADDR=10.0.0.1 NETMASK=255.255.255.255 Maybe you've been using a netmask which overlaps with some of the addresses configured on your eth interfaces : Don't do that for those "dummy" addresses. Matthias </pre> </blockquote> I found the problem. I was attempting to `ifup lo:0` to bring up the specific interface. Apparently you can not do this anymore. You have to do `ifup lo` and let it bring up all aliases together. -Patrick </body> </html>