01-18-2013 07:13 AM
Hi,
I configured a new serverfarm with leastconns predictor for two servers on our ACE module Version A2(2.3). Probes (show probes XX detail) to the servers are successful and both servers are operational (show serverfarm APPLI detail) but connections are directed only to one server.
When I deactived the server which is receiving the connections (no inservice), the ACE start to direct connection to the second server.
There are several serverfarm, configured the same way, that are Loadbalancing traffic as correctly.
Here is a sample of my config
serverfarm host TEST_443
predictor leastconns
probe TEST_443_PROBE01
rserver TEST_RS01 443
inservice
rserver TEST_RS02 443
inservice
sticky http-cookie TEST_HTTPS TEST_443_STKY
cookie insert
timeout 720
replicate sticky
serverfarm TEST_443
probe http TEST_443_PROBE01
port 443
interval 20
passdetect interval 60
passdetect count 5
request method get url /test
expect status 302 302
connection term forced
policy-map type loadbalance first-match TEST_L7PLB_HTTPS
class class-default
sticky-serverfarm TEST_443_STKY_SF
insert-http X-Forwarded-Proto header-value "https"
insert-http X-Forwarded-For header-value "%is"
policy-map multi-match SLB-HTTP-POLICY
class TEST_L4VIP_HTTPS
loadbalance vip inservice
loadbalance policy TEST_L7PLB_HTTPS
loadbalance vip icmp-reply active
loadbalance vip advertise active
nat dynamic 1 vlan 202
appl-parameter http advanced-options PERSIST
ssl-proxy server TEST_SSL_PROXY_SERVER
PS : ACE uptime is 291days, could that impact ACE behavior ?
Thanks for any troubleshooting hints
Solved! Go to Solution.
01-18-2013 07:30 AM
Since you are using a sticky serverfarm, the ACE will check the cookie (because cookie sticky is configured) and if it is still valid it will send it to the rserver that corresponds to the cookie. As long a the cookie is valid and the rserver is still up, the connection will be sent there. New connections without a cookie or a valid cookie will be sent to a rserver based upon the least connections algorithm.
-Alex
01-18-2013 07:30 AM
Since you are using a sticky serverfarm, the ACE will check the cookie (because cookie sticky is configured) and if it is still valid it will send it to the rserver that corresponds to the cookie. As long a the cookie is valid and the rserver is still up, the connection will be sent there. New connections without a cookie or a valid cookie will be sent to a rserver based upon the least connections algorithm.
-Alex
01-18-2013 08:08 AM
Agreed Richard,
the problem is that all connections are sent to one server only, new connections are not split between the two servers.
thank you
01-21-2013 07:40 AM
Thanks Alex and stephen for your replies.
The config is OK, so is the ACE module. The problem was related to the way the customer tested its applications...he was not indeed clearing his browser cache and cookies before each connection as he was supposed to do.
01-21-2013 05:54 AM
Looking at this on my phone but it looks like you L7 policy is referencing a sticky server farm that does not exist.
ie TEST_443_STKY_SF is incorrect name for sticky
If that's not it. Then check that the first server actually has a number of conns on it when a new connection is established. Sometimes when both servers have 0 conns - new incoming conns will always go to the first server
Regards
Stephen
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