ACE, max conns limit and oversubscription issue

[Krzysztof Obara]

Hi,

I have a question regarding the following output:

show serverfarm SFARM detail 

...

---------------------------------
                                                ----------connections-----------
       real                  weight state        current    total      failures
   ---+---------------------+------+------------+----------+----------+---------
   rserver: REAL_1
       10.0.0.1:80           8      MAXCONNS     10435      65590       130
         description          : -
         max-conns            : 10000
         min-conns            : 9950

...

There is a sticky source ip configured for primary serverfarm + backup serverfarm (with no sticky). Do you know why we can see more current connections than max-conns limit?

The sticky for primary serverfarm could cause that issue?

Regards,

Krzysztof

[Kanwaljeet Singh · Accepted solution]

Hi Krzysztof,

Normally the current connection counter is number of ESTABLISHED + EMBRYONIC connections. So as soon as ACE forwards the SYN, the current counter is incremented and if the connection establishes, total connection counter is incremented or else failure.

Having said that, i still believe it should not show more than MAX-CONNS limit unless Max-conns is only for ESTABLISHED.

I would suggest opening a TAC case to further investigate this. There have many issues related to these counters which all were cosmetic and had no real impact on the functionality of device itself.

Regards,

Kanwal

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