Forum Discussion

muhammad_Tanvir's avatar
muhammad_Tanvir
Icon for Nimbostratus rankNimbostratus
Sep 01, 2021

log for iRules:Data Group List

Hi

  • Our exchange users connects to server through F5 Vitual server.
  • I have a data group list which has 172 IPs.
  • we have irule as follows
  • I want to enable an log file to find out which IPs are still connecting to exchange server. please help me as I am very new to F5
  • irule attached to virtual server

when CLIENT_ACCEPTED {
    set accepted_snat "172.16.0.174"
 
    if { [ class exists smtp_relay_allowed ] }
    {
        if { [class match [IP::client_addr] equals smtp_relay_allowed] }
        {
            snat $accepted_snat
        } else {
            snat automap
            log local0. "IP not allowed to relay: [IP::client_addr]"
        }
    } else {
        snat automap
        #log local0. "IP not allowed to relay: [IP::client_addr]"
    }
}
BIG-IP
security

5 Replies

Sort By
  • oguzy's avatar
    oguzy
    Icon for Cirrostratus rankCirrostratus
    Sep 01, 2021

    Hi Muhammad Tanvir,

    I think your irule is almost correct. Did it not work as you expected? I assume that as you already have a data group list named as "smtp_relay_allowed", initial checking of existence of this data group is not necessary. For simplicity;

    when CLIENT_ACCEPTED {
  set accepted_snat "172.16.0.174"
  if { [class match [IP::client_addr] equals smtp_relay_allowed] } {
    snat $accepted_snat
    log local0. "IP allowed to relay: [IP::client_addr]"
  } else {
      snat automap
      log local0. "IP not allowed to relay: [IP::client_addr]"
  }
}
    • muhammad_Tanvir's avatar
      muhammad_Tanvir
      Icon for Nimbostratus rankNimbostratus
      Sep 02, 2021

      Thanks Oguzy for your kind reply.

      I rule works fine.

       

      I want to update the data group list which has 172 IPs. List is 4 years old and a lot of systems are gone now. Before I update the list I want to enable logs and find out which systems are still actively using the virtual server

       

      Could you please help me out to find out which logs I need to configure to capture IPs. There are many types Kind regarfds

      Tanvir

       

      • oguzy's avatar
        oguzy
        Icon for Cirrostratus rankCirrostratus
        Sep 02, 2021

        Hi Tanvir,

        As we specify "log local 0.", you should check "Local Traffic" Log on GUI or /var/log/ltm file on CLI. You can use both GUI and CLI. If you use CLI, you can check rotated (old ltm) logs via regex.

        If you login via ssh to your BIG-IP device, you can try the following command:

        grep "IP allowed to relay" /var/log/ltm*

        Then you can inspect the IP address requesting to your virtual server.