This solution applies to all Barracuda Networks products.
You can use custom arguments with the Tcpdump tool on your Barracuda Networks product to gather and filter various network traffic data. Navigate to Advanced > Troubleshooting. Press Begin TCPDump to execute a tcpdump command. This will open a new window displaying the current traffic flowing through the device.
To see traffic on a specific port you can use this argument:
-lnxX -s 1524 port <port #>
-lnxX -s 1524 port 25
If you know the hostname or IP address you want to filter for, you can add the arguments seen in the examples below.
-lnxX -s 1524 port 25 and host 18.104.22.168
-lnxX -s 1524 port 25 and host mail.example.com
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