Hallo Sebastian. First of all, thank you very much for your time and consideration. I forgot to mention in my previous post that I actually have those sysctl parameters specified. I also executed sysctl -p to activate them. So, I guess that is not the problem.
A question regarding the sysctl parameters; Isn't it ok to only specify 'all' as I suppose it include ALL interfaces? net.ipv4.conf.all.arp_ignore = 1 net.ipv4.conf.all.arp_announce = 2 Not that I did this, but it's just bothering me :) Also, the property name isn't the most appropriate if you ask me. If you say conf.eth0.arp_ignore = 1, then I understand out of it that arp requests should be ignored on eth0. Which isn't really the case, they should only be ignored on the alias. Or am I totally wrong here. Pieter On Wed, 2008-11-12 at 12:19 +0100, Sebastian Geib wrote: > Hi Pieter, > > Pieter Temmerman schrieb: > > In every tutorial I have read on VLS, it stated that in order to receive > > traffic on the VIP, the real servers should have the VIP assigned to the > > lo:0 alias interface. > > > > When I do this, that particular server is unreachable and is either able > > to reach other servers in the network. When I remove the lo:0 alias, > > everything is back to normal again. > > > > I solved this by instead creating the VIP on tunl0 instead of lo:0. But > > still, I would like the know the reason why it is failing. > > > > Is this a problem with my distribution or am I overlooking something > > crucial? > > > > I have Centos 5.2 (2.6.18-1.17.el5). > actually your distribution shouldn't play a role in that as it seems to > be a general problem with ARP requests from what I can guess. If you > haven't made any changes to your sysctl.conf then your lo:0 interface > acts like a real interface and when the network is asked for the MAC > address which belongs to your VIP and this request comes in on any of > your machines real interfaces that machine answers too - which it > shouldn't - because it thinks it has the IP address and should tell > everyone about it. > > You have two ways out of this: > 1. Compile your kernel with dummy interface support with NOARP enabled. > This is an option I am using in some setups but I generally prefer the > second one as it is pretty much painless and easy to implement. > 2. Edit your /etc/sysctl.conf and add the following lines: > net.ipv4.conf.eth0.arp_ignore = 1 > net.ipv4.conf.eth0.arp_announce = 2 > net.ipv4.conf.eth1.arp_ignore = 1 > net.ipv4.conf.eth1.arp_announce = 2 > net.ipv4.conf.all.arp_ignore = 1 > net.ipv4.conf.all.arp_announce = 2 > > Obviously eth0 and eth1 need to be your real network interfaces where > ARP requests should be answered for the IP addresses bound to those > interfaces. Afterwards everything should be fine. > Afterwards you do a "sysctl -p" and everything should be fine. > > Sebastian > _______________________________________________ LinuxVirtualServer.org mailing list - [email protected] Send requests to [EMAIL PROTECTED] or go to http://lists.graemef.net/mailman/listinfo/lvs-users
