Hi, I understand why this is necessary on the realservers but I'm not sure why that would be necessary on the load-balancers. Now I'm wondering if in the example setup the load-balancers and real servers are supposed to be the same machines but since with the DR/gate method the response packets may not be routed back through the load-balancers this cannot work either.
Regards, Dennis On 09/04/2012 06:34 AM, Carlos Xavier wrote: > Hi. > > The virtual IP on the loopback are needed for the real servers, so as they > can answer the packets sent to them. > You also need to edit the file /etc/sysctl.conf to disable the reply to arp > requests of the virtual addresses configured on the loopback. > This is what I had to add to my web servers sysctl.conf, adjust it to your > configuration: > ######## > # Enable configuration of arp_ignore option > net.ipv4.conf.all.arp_ignore = 1 > > # When an arp request is received on eth0, only respond if that address is > # configured on eth0. In particular, do not respond if the address is > # configured on lo > net.ipv4.conf.eth0.arp_ignore = 1 > > # Ditto for eth1, add for all ARPing interfaces > net.ipv4.conf.bond0.arp_ignore = 1 > net.ipv4.conf.vlan0.arp_ignore = 1 > > > # Enable configuration of arp_announce option > net.ipv4.conf.all.arp_announce = 2 > > # When making an ARP request sent through eth0 Always use an address that > # is configured on eth0 as the source address of the ARP request. If this > # is not set, and packets are being sent out eth0 for an address that is on > # lo, and an arp request is required, then the address on lo will be used. > # As the source IP address of arp requests is entered into the ARP cache on > # the destination, it has the effect of announcing this address. This is > # not desirable in this case as adresses on lo on the real-servers should > # be announced only by the linux-director. > net.ipv4.conf.eth0.arp_announce = 2 > > # Ditto for eth1, add for all ARPing interfaces > net.ipv4.conf.bond0.arp_announce = 2 > net.ipv4.conf.vlan0.arp_announce = 2 > ######## > > I´m configuring some servers to work with ldiretord, but my approach as a > little bit different, I already have a cluster working for mysql and they > will be the ldirector manager and I configured anther cluster just to manage > http/https > > Regards, > Carlos > > > -----Mensagem original----- > De: Dennis Jacobfeuerborn [mailto:[email protected]] > Enviada em: segunda-feira, 3 de setembro de 2012 23:28 > Para: [email protected] > Assunto: [Pacemaker] "Using ldirectord" page question > >> Hi, >> I'm trying to set up a redundant load-balancer using pacemaker and > ldirectord and found an example for the configuration on the following page: >> http://www.clusterlabs.org/wiki/Using_ldirectord > >> What I don't understand is the following part: >> "This gives you the virtual IP address and ldirectord running together in > a group (ip-lvs) on one node, and the same virtual IP address assigned to > the loopback address on all other nodes. This is necessary to make the > routing work correctly. " > >> Why is the configuration of the IP on the lo interfaces necessary for > routing? >> As far as I understand is the VIP only needs to run on the active node > that is also running the ldirectord daemon. Once the failover happens both > move over to the new active node and the setup should continue to work as > before. Is there something I'm missing here? > >> Regards, >> Dennis > > > > > _______________________________________________ > Pacemaker mailing list: [email protected] > http://oss.clusterlabs.org/mailman/listinfo/pacemaker > > Project Home: http://www.clusterlabs.org > Getting started: http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf > Bugs: http://bugs.clusterlabs.org > _______________________________________________ Pacemaker mailing list: [email protected] http://oss.clusterlabs.org/mailman/listinfo/pacemaker Project Home: http://www.clusterlabs.org Getting started: http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf Bugs: http://bugs.clusterlabs.org
