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  • 1.  Gateway Pcap

    Posted 08-24-2023 05:54

    Dear all,

    I hope you're all doing well.

    Whether it's possible to take PCAP from gateways, if possible, please let us know the procedure.

    Gateway Model: X2020


    Jagadesh Kumar R
    Information Security Group, Manager
    The Karur Vysya Bank Limited

  • 2.  RE: Gateway Pcap

    Posted 08-24-2023 07:28

    Hi Jagadesh Kumar,

    Please go through this link:
    I hope this will be useful to you. 

    𝐌𝐒𝐭𝐞𝐬𝐑 𝐌𝐞𝐑𝐭𝐚
    Senior Security Consultant

  • 3.  RE: Gateway Pcap

    Posted 08-27-2023 13:23

    Hello Jagadesh,

    Thank you for the post, you can follow the below steps,

    To record a pcap file with tcpdump:

    Enable TCP dump: 

    1. tcpdump_on 

    2. run tcpdump as usual 

    3. tcpdump_off 

    Step 3 is very important, if it is not be done, the gateway performance might be affected until you will run this step (reboot will also stop it). 

    Record a pcap file with tcpdump

    Once you're logged in as the root user run the following command: 

    tcpdump -i ethX -s0 host and port YYY -w /var/tmp/name.pcap 

    • Replace ethX with the interface number (eth1, eth2, eth3, etc). Do not use "any" when recording pcap files for support purposes as those cannot be used by us. You can check the interface that is monitoring the traffic by reviewing the gateway configuration via impcfg menu or using command: impctl gateway show
    • The "-s0 " is crucial so packets do not get truncated by tcpdump's default configuration.
    • Replace with the relevant IP address (when applicable). This can be a client IP or a server IP address
    • Replace YYY with the relevant port number (when applicable).
    • The -w option indicates where the captured traffic should be captured to, in the example above it will be saved to a file called name.pcap under the /var/tmp folder.

    Here is an example: 
    tcpdump -i eth2 host and host -w /var/tmp/case001.pcap 

    Syed Noor Fazal
    Product Support Engineer