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bwilliam's avatar
bwilliam
Icon for Cirrus rankCirrus
May 06, 2021

VIP Client Logging "Not RFC1918"

Hi, I have gone through the dev/central site and found an irule capturing VIP client connections . The problem I have is that I don't need to log internal IP space or RFC1918 networks. I want to log all other public IP client connections.

This is the irule I am using. This is my first time working with any programming language and I cant see how the logic will flow.

when HTTP_REQUEST {
 log local0. "clientIP:[IP::client_addr] accessed
 [HTTP::host][HTTP::uri]"
]

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iRules
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  • bwilliam's avatar
    bwilliam
    May 11, 2021

    Thank you Alex for the response. I ended up going with this irule. Initially after applying the irule I was still logging the private networks. What I found is that I had to surround the private_net with quotes. After doing this I only saw public networks.

     

    Now I need to send it to a remote syslog instead of logging local0. I just have to research how those lines of code will look like.

     

    when HTTP_REQUEST {
  if { not ([class match [IP::client_addr] equals "private_net"])} {
 
  log local0. "clientIP:[IP::client_addr] accessed
  [HTTP::host][HTTP::uri]"}
}

     

  • bwilliam's avatar
    bwilliam
    Icon for Cirrus rankCirrus
    May 11, 2021

    Thank you Alex for the response. I ended up going with this irule. Initially after applying the irule I was still logging the private networks. What I found is that I had to surround the private_net with quotes. After doing this I only saw public networks.

     

    Now I need to send it to a remote syslog instead of logging local0. I just have to research how those lines of code will look like.

     

    when HTTP_REQUEST {
  if { not ([class match [IP::client_addr] equals "private_net"])} {
 
  log local0. "clientIP:[IP::client_addr] accessed
  [HTTP::host][HTTP::uri]"}
}

     

    • AlexBCT's avatar
      AlexBCT
      Icon for Cumulonimbus rankCumulonimbus
      May 11, 2021

      Ahyes, sorry I missed that.

      Regarding sending to remote log, have a look at HSL logging; https://clouddocs.f5.com/api/irules/HSL__open.html

      This is the most efficient way to send logs to remote servers.

  • AlexBCT's avatar
    AlexBCT
    Icon for Cumulonimbus rankCumulonimbus
    May 06, 2021

    First of all, congrats on your first dip in the iRules pool! :)

     

    A couple of suggestions;

    • The bracket on line 4 should be a curly bracket } instead of a square bracket, this is the closing bracket for the one on line 1.
    • The log statement should work the way you have it at the moment, and will log the client address, as well as the full URL.
    • If you want to add the logic to only look for non-private IP's, you can add an "if" statement, similar to this one (the "private_net" is a data group that's already configured on the system with the private IP ranges in it);

     

    when HTTP_REQUEST {

    if { !([class match [IP::client_addr] equals private_net])} {

    log local0. "clientIP:[IP::client_addr] accessed [HTTP::host][HTTP::uri]"

    }

    }

     

    Hope this helps.