Hi,
We're using LVS-DR to loadbalance HTTP/HTTPS requests to three
webservers. Both active and backup LVS servers have fully updated CentOS
5.1. ARP problem is solved with arptables_jf. All this time i have been
restarting realservers during the night under very little load and s at
all. But lately one of the realservers crashed during the day and when
it came back it was automatically added back to the LVS and all but no
new requests were sent to it. Ipvsadm showed it had a lot of
ActiveConn's and zero InActConn's. These numbers remained the same for
10 or more minutes and then ActiveConn started decreasing slowly. Once
the ActiveConn was lower than the other realservers had, new requests
started to reach the server and InActConn increased from 0. I could
reproduce this later when i took a realserver down myself and noticed
that the more connections there were during the crash and after, the
bigger static count of ActiveConn's appeared for the crashed server once
it came back. Neither LVS restart or "ipvsadm --zero" helped.
It seems to me that when one of the realservers disappears, LVS doesn't
close the open connections and they just hang there until timeout comes.
Definately doesn't seem like an ARP prolem.
Oh.. and i should mention that i'm using firewall marks and lc scheduler.
Any help would be appreciated!
Thanks,
Janar Kartau
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