Hi On Sat, 2008-05-31 at 09:14 -0500, Memblin wrote: > If I remove the realserver from the ipvs config that is currently getting > all the traffice (say num 1), the traffic does go to the other realserver > (say num 2). Then when I put number 1 back into the ipvs configuation > the traffice stays with number 2. If I do nslookups from a windows > box it looks like Windows actually asks for like 8 things per single > request and those get spread out between both servers normally.
We need to look a bit more deeply here at what's happening. Firstly, you're using NAT - this makes monitoring things a bit easier because the director has an idea of connection state due to it seeing all packets in both directions (in -DR it can have an idea of state but can get a little confused if packets go astray, which is why -DR tends to report "inactconn" rather than "actconn"). Secondly, you're configuring a connectionless service. DNS over UDP is "fire and forget" - the application is responsible for retries, rather than the OS protocol stack - and (this is the important bit) UDP is stateless. If you look at the connections from a single client on an unloaded system, you're likely to see what you do see - every packet goes to the same host, because LVS views them as a "session". On the balance of probabilities, a DNS server will receive many thousands of queries from many hundreds/thousands (or more) of hosts. Over time from a cold start to fully loaded, they will be shared out amongst the realservers according to the scheduler being used and the weight assigned (a word of advice - set the weights to something higher than 1. It makes future tuning *far* easier if you start with everything having a weight of 100, say). You could also look at "ipvsadm --set" and tune down the UDP timeout to something like one or two seconds. Unfortunately, using a small number of clients (where small is some number greater than 0) doesn't give real-world results. Graeme _______________________________________________ LinuxVirtualServer.org mailing list - [email protected] Send requests to [EMAIL PROTECTED] or go to http://lists.graemef.net/mailman/listinfo/lvs-users
