> I'm working on load balancing some sqlgrey servers using ipvsadm (non of the > other bells and whistles, just the director itself). Anyway, at first glimps > things look like they are running well until I find that I have a lot of > connections in ESTABLISHED mode running on the sqlgrey real servers. Looking > at the director there are corresponding active connections, and finally, > looking at postfix, there are only a few active connections. I have worked > with the ipvsadm group to ensure arp routing and other items are taken care of > as per their recommendations. > > What I am seeing is that postfix seems to be sending the close request down > the pipe to the load balancer and the director isn't responding (properly?), > postfix is then marking the connection as FIN_WAIT, and finally, the > connection is being dropped by the postfix server. The problem appears to be > that the director isn't either passing the request forward or isn't > acknowledging it at all. > > Now, when I swing the postfix directly to the IP of one of the real nodes, no > problem. So, I was thinking maybe persistence. So I change director to be > sticky for 15 minutes, but no go. > > Has anyone seen this behavior before on a load balanced policy server? > > Anyone have any ipvsadm scripts for a policy server they would like to share? > I'm using wlc nat'ed connections currently.
Things work much better. The lost connections were because of iptables. I have this rule early on for server that has the director. I guess the ACK FIN is an technically an invalid state... -A INPUT -p tcp -m conntrack --ctstate INVALID -j LOG --log-prefix "FW-I BF: " -A INPUT -p tcp -m conntrack --ctstate INVALID -j REJECT --reject-with icmp-port-unreachable Apr 26 04:36:02 wall1 kernel: FW-I BF: IN=br0 OUT= PHYSIN=eth1 MAC=00:50:56:b1:63:bc:00:0c:29:92:be:b7:08:00 SRC=10.80.66.24 DST=10.80.55.11 LEN=52 TOS=0x08 PREC=0x00 TTL=64 ID=40835 DF PROTO=TCP SPT=52114 DPT=3917 WINDOW=363 RES=0x00 ACK FIN URGP=0 > Gary
