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ozdemircili_696's avatar
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Jan 11, 2011

Blocking a host




I have been managing a BIG-IP 9.4.8 Build 355.0 Final for out tomcat nodes. I have a monitor setup for all the nodes in the pool checking if the tomcat application is working or not. I have an interval of 5 seconds and timeout of 15 seconds.




The monitor is the following:




GET /app/ HTTP/1.1\r\nConnection: Close\r\nHost: \r\n\r\n






The problem is although the application starts when we start the tomcat it needs about 40 seconds to get the cache and do the maintanance and will not respond until finishes all these.



As we are using the monitor above and as when the tomcat starts up and /app/ responds I need F5 to block the machine for about a minute when it gets a timeout.




Can this be done? With an Irule possibly?




Thank you in advance.






1 Reply

  • So, Tomcat responds to the health monitor right away but you don't want it to process any traffic for 60 seconds or so?

    If you were using 10.x, I'd say to use the "Time Until Up" option in monitors which accomplishes exactly what you need.

    An option in 9.x might be to use the "Slow Ramp" option on the pool members screen.

    Slow Ramp Time
        Specifies the duration during which the system sends less traffic to a newly-enabled pool member. The amount of traffic is based on the ratio of how long the pool member has been available compared to the slow ramp time, in seconds. Once the pool member has been online for a time greater than the slow ramp time, the pool member receives a full proportion of the incoming traffic. Slow ramp time is particularly useful for the least connections load balancing mode.

    As this doesn't completely eliminate traffic from getting to the pool member, it wouldn't be a perfect solution.

    As far as your monitor goes...why not make one that requires tomcat to be completely up before it responds properly?