Hi I have a multi server setup and I am using a network load balancer to distribute across my 4 mail stores. I setup an external IP address on the load balancer and have configured the setup to use a virtualHostname and 4 virtualIPAddresses - each one being on a proxy. The idea is that you connect to FQDN and no matter which mailbox your account lives on, you always see FQDN in the url location bar.
This has been working up until yesterday. What occasionally happens is that users go to the FQDN and log in, but then instead of the URL remaing as FQDN, it changes to mail1 or mail2 or whichever mail store their account resides.
The proxy servers are not seperate servers, the service runs on the same devices as the mail stores.
What is infuriating is that the problem is intermittent.
What i have noticed in the nginx logs is:
2008/09/10 15:27:48 [error] 24315#0: *545 upstream timed out (110: Connection timed out) while reading response header from upstream, client: 192.168.0.4, server: zimbra1-vm1.somedomain, URL: "/service/soap/NoOpRequest", upstream: "http://192.168.16.230:8080/service/soap/NoOpRequest", host: "mail1.somedomain", referrer: "http://mail1.somedomain/zimbra/"
Now the IP address for the proxy on this server is 192.168.16.50 and it resides on the same machine as the 'upstream client' 192.168.16.230 so why it is getting a connection timed out is beyond me.
How can I get more debug info out of nginx?