On Sun, Jul 06, 2003 at 06:36:06AM -0400, Hagibis Fan wrote: > No, I wont go with round-robinning > DNS A entries--all traffic should go to > the main server at all times but will > fallback to our other servers when thats > down. Playing around with TTL or any
What you're describing hear is *not* load balancing, but high availability service. Load balancing will do something totally different from what you describe, it will balance the load among your entire pool of servers, not concentrate traffic to a single server and then fallback to the other servers if that goes down. > other DNS trick wont do either. Either > its intantaneous or I wont do it. > Whether this is possible or feasible depends on the lengths you're willing to go and who will have access to your services. If your primary and backup servers live on different networks and you want your service to be accessible to the Internet at large, well, I'm afraid to say that you cannot achieve instantaneous failover. The only way to do it is round robin DNS and/or TTL tricks. If you're concerned about accessibility of your website to assorted locations, and have the money to spare, buy service from Akamai. The largest websites like Yahoo and CNN use their system. If you have a closed set of clients for your web service, you can set up a VPN for your primary and backup servers and your clients and then run Heartbeat (http://www.linux-ha.org/) between your primary and backup servers. Assign a cluster IP address that passes between your primary and backup servers. Although the docs for heartbeat say you should be running the heartbeat over a dedicated ethernet or serial line, there is no reason why you can't run it over your normal network interface as well. That will provide near instantaneous failover. > I've tried to read up BGP but I cannot > understand it--that technology will be > beyond me. BGP won't help you here. You aren't trying to do IP load balancing at all, and BGP is intended to load balance arbitrary traffic from two different upstream sources to a single destination. It's *totally* unrelated to server load balancing, much less high availability. -- Rafael R. Sevilla <dido at imperium dot ph> +63(2)8123151 Software Developer, Imperium Technology Inc. +63(917)6290861 "Necessity is the plea for every infringement of human freedom. It is the argument of tyrants, it is the creed of slaves." -- Philippine Linux Users' Group (PLUG) Mailing List [EMAIL PROTECTED] (#PLUG @ irc.free.net.ph) Official Website: http://plug.linux.org.ph Searchable Archives: http://marc.free.net.ph . To leave, go to http://lists.q-linux.com/mailman/listinfo/plug . Are you a Linux newbie? To join the newbie list, go to http://lists.q-linux.com/mailman/listinfo/ph-linux-newbie
