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Jeremy_Bridges_'s avatar
Jeremy_Bridges_
Icon for Nimbostratus rankNimbostratus
Aug 21, 2009

Custom TCP Monitor

I am looking to do some custom TCP monitoring with a custom application that we need to monitor with the F5. Essentially, the application's thread handling logic will hang unless a specific set of se...
management
monitoring
Jeremy_Bridges_'s avatar
Jeremy_Bridges_
Icon for Nimbostratus rankNimbostratus
Aug 28, 2009
Alright, I have implemented an external monitor script and the monitor profile needed to run the script from within the F5. Running the script from the prompt works fine. The following call returns "UP" when the application is listening properly and nothing when it is not. 

bash runBerryCall 10.1.1.1 18888

However, the same pool member is marked down by the monitor when the BIG-IP runs the external monitor. See attachment for the monitor's settings.

I'm guessing the reason for this is the IP address format that is passed to the script. From the articles I have found, it seems the IP is passed in "IPv4 mapped address notation":

http://devcentral.f5.com/Default.aspx?tabid=63&articleType=ArticleView&articleId=151

For, netcat doesn't like the format of the IP address. This fails with the following error: 

  
 bash runBerryCall ::ffff:10.1.1.1 18888  
 ::ffff:10.1.1.1: forward host lookup failed: Unknown host

NetCat 6 fully supports IPv6. How can I figure out what version of netcat is installed on the BIG-IP?