Wireshark mailing list archives
Re: About filter "udp && !icmp"
From: Guy Harris <guy () alum mit edu>
Date: Tue, 16 Apr 2013 15:37:33 -0700
On Apr 16, 2013, at 3:28 PM, delarge <charlie () linuxers cl> wrote:
I'm a new user of Wireshark and I'm capturing UDP traffic. Startly I used the "udp" filter but appears some undesirable ICMP packets, so then googling I've found the "udp && !icmp" filter to avoid capture ICMP packets. It's all right till here, but when I export the capture as plain text, the ICMP packets appear again. Seems like the filter just works in the main screen of Wireshark. What can I do to capture just UDP traffic?
Use the filter "udp", and use it as a *capture* filter (when starting the capture with Capture -> Options) rather than as a *display* filter (in the main screen). "udp && !icmp" is used as a *display* filter to handle the fact that some ICMP packets contain a partial or complete copy of the packet for which they're reporting a problem, so they might contain UDP packets. For *capture* filters, only the outermost packet layer is tested, so "udp" matches only UDP packets, not ICMP packets that happen to contain a copy of a UDP packet. ___________________________________________________________________________ Sent via: Wireshark-users mailing list <wireshark-users () wireshark org> Archives: http://www.wireshark.org/lists/wireshark-users Unsubscribe: https://wireshark.org/mailman/options/wireshark-users mailto:wireshark-users-request () wireshark org?subject=unsubscribe
Current thread:
- About filter "udp && !icmp" delarge (Apr 16)
- Re: About filter "udp && !icmp" Guy Harris (Apr 16)
- Re: About filter Christopher Maynard (Apr 16)
- Re: About filter "udp && !icmp" Guy Harris (Apr 16)
- Re: About filter "udp && !icmp" Christopher Maynard (Apr 16)
- Re: About filter "udp && !icmp" delarge (Apr 17)
- Re: About filter Christopher Maynard (Apr 16)
- Re: About filter "udp && !icmp" Guy Harris (Apr 16)