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AdityaKurundkar's avatar
AdityaKurundkar
Icon for Altostratus rankAltostratus
May 02, 2024

GTM Packet Capture command

Hi All,

 

I have started working on F5 GTM recently and stuck with the tcpdump commands for it.

 

Need help on tcpdump commands for wideip to check if the wideip is working correctly.

 

Also are there any step by step guide to check and troubleshoot wideip application issue.

 

 

application delivery
  • F5_Design_Engineer's avatar
    F5_Design_Engineer
    Icon for MVP rankMVP
    May 02, 2024

    Hi Aditya,

     

    You can try using the following formats by changing the host IP as per your configuration.

     

    tcpdump -vvv -s0  -nni 0.0:nnnp udp port 53 and host 1.2.3.4 -w /var/tmp/$(/bin/hostname)_$(date +%Y-%m-%d)_$(date +%H:%M).pcap

    First, find out which interface you want to sniff with the "ifconfig" command. If the destination server is located on an interface called "vlan1275" you can dump all DNS traffic to a specific IP address thus

    tcpdump -i vlan1275 udp port 53 and host 1.2.3.4 -w /var/tmp/$(/bin/hostname)_$(date +%Y-%m-%d)_$(date +%H:%M).pcap

    You can refer following articles 


    K411: Overview of packet tracing with the tcpdump utility
    https://my.f5.com/manage/s/article/K411

     

    K00463541: A breakdown of the tcpdump utility, recommended actions, and information to help you use and apply it to the BIG-IP.
    https://my.f5.com/manage/s/article/K00463541

     

    HTH

    🙏