Hi Falko, do you think it would be possible to install load balancers directly on the apache nodes? I have a LB setup now with Xen but since its giving poor results (CPU capacity is around 50%) compared to a straith install, I want to get rid of virtualization. Thanks Marc
Yes, if you have more than one IP on the server or if Apache uses a different port than 80. Regarding your performance problems: are you using image-based or LVM-based VMs? Images cause a lot of hard drive IO, so you should use LVM on a production system. http://www.howtoforge.com/using-xen-with-lvm-based-vms-instead-of-image-based-vms-debian-etch
I was thinking that IPVS wasnt allowing to put nodes on load balancers because of ip forwarding. The problem is not really with HD i/o (Xen is on a partition) but for some reasons when I do CPU benchmarks I get poor results with Xen compared to a straith install. Since software load balancers (such as ldirectord + heartbeat) use very little ressources, I think its better to put it directly on the first two webserver nodes 1)to save on hosting (less boxes) 2)less management and 3)better use of load balancers ressources. Im slowly working on an updated version of : http://howtoforge.com/the-perfect-l...ervers-running-xen-on-ubuntu-8.04-hardy-heron Here are the points I will improve : 1)Better/easy scalability 2)No more virtualization for better performance 3)Storage in a "cloud" instead of rsyncing files between servers (eg http://blogama.org/node/78) 4)Single management interface (ISPConfig 3??) I did not test it yet but I believe it would be possible to use ISPConfig 3 to control a load balanced + HA cluster with very little modifications... Will keep you updated Thanks Marc btw cookie expire pretty quickly on howtoforge... anoying with long posts...
