Forum Discussion

Ford_Prefect's avatar
Oct 08, 2020

Management connection to Standby vCMP guest on i7800 chassis is extremely slow

At first glance, a simple problem arose - a very slow connection to the F5 management interface, it barely connect users to Web GUI, ssh, iControl Rest API. I noticed the messages in the logs:

  • server reached MaxRequestWorkers setting, consider raising the MaxRequestWorkers setting
  • AUTHCACHE Error processing cookie XXXXXXXXXXXXXXXXXXXX - Cookie user mismatch

There is a bot with the Manager role, which connects ~ 3 times / min via iControl REST. I had increased the value of ‘Maximum HTTP Connections To Configuration Utility’, and thus that didn’t help, disabled the bot. Somehow it helped to increase the connection speed a little, but now the most interesting part in detailed.

There are 2 i7800 v15.1.0.4 chassis running, each with 2 different guests connected to peers on the neighbor chassis by HA-failover configuration.

The problem arises with Standby vCMP guest, which works in HA pair with a vCMP guest on a neighbor chassis with identical config. The modules and resources provisioned (LTM is enabled) are the same, the load is small, swap is not used, SMART was successfully passed. On the active device paired with the problematic one there are more or less the same messages in logs - nothing critical and there also exist a bot user that logs in ~ 3 times / min and no problems with management are noticed.

The file transfer speed from the problematic vCMP guest over SSH is 254 Bps, and from its neighbor on the same chassis - 10.6 Mbps.

Can you tell me where to search, please? I will be very grateful, I do not know what the problem might be if everything is the same, and the problem does appear on 1 device out of 4.