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MikroTik App
 
signal
newbie
Topic Author
Posts: 33
Joined: Thu Aug 19, 2004 4:44 am

Is packet sniffing broke in 2.8.11?

Thu Sep 09, 2004 5:24 pm

I am trying to do some basic packet sniffing. I setup my sniffer:

[admin@BIOMED_MAIN] tool sniffer> print
interface: all
only-headers: yes
memory-limit: 2000
file-name:
file-limit: 10
streaming-enabled: no
streaming-server: 0.0.0.0
filter-stream: yes
filter-protocol: ip-only
filter-address1: 192.168.3.76/0:0-65535
filter-address2: 192.168.3.76/0:0-65535
running: yes


because I only want to capture packets from 192.168.3.76

Yet, when I start, then stop it, and then check "packet print", I see traffic from going to and from the router to all 192.168.3.x addresses, not just 192.168.3.76. Also, no matter what, I have never seen an icmp packet logged in sniffer, which is bizarre.

I am trying to do a ping from the router (192.168.3.254) to the host (192.168.3.76) and capture a sniff of this. I have also tried setting the sniffer as:

[admin@BIOMED_MAIN] tool sniffer> print
interface: all
only-headers: yes
memory-limit: 2000
file-name:
file-limit: 10
streaming-enabled: no
streaming-server: 0.0.0.0
filter-stream: yes
filter-protocol: ip-only
filter-address1: 192.168.3.76/0:0-65535
filter-address2: 192.168.3.254/0:0-65535
running: yes

But it doesn't matter. I "start", do my pings, then "stop", then "packet print" and all I see is my telnet traffic to the router but not the pings.

Any ideas?
 
User avatar
mag
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Posts: 376
Joined: Thu Jul 01, 2004 12:32 pm
Location: Cologne, NRW, Germany
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Re: Is packet sniffing broke in 2.8.11?

Thu Sep 09, 2004 5:36 pm

...
filter-address1: 192.168.3.76/0:0-65535
filter-address2: 192.168.3.76/0:0-65535
...
Any ideas?
should the netmask not be set to "/32"?
 
signal
newbie
Topic Author
Posts: 33
Joined: Thu Aug 19, 2004 4:44 am

Thu Sep 09, 2004 6:14 pm

Yes, your right, but it still does not seem to capture packets to/from the router of type icmp:

[admin@BIOMED_MAIN] tool sniffer> print
interface: all
only-headers: yes
memory-limit: 2000
file-name:
file-limit: 10
streaming-enabled: no
streaming-server: 0.0.0.0
filter-stream: yes
filter-protocol: ip-only
filter-address1: 192.168.3.254/32:0-65535
filter-address2: 192.168.3.76/32:0-65535
running: no


I start, then ping, then stop, and the packet buffers are empty
 
changeip
Forum Guru
Forum Guru
Posts: 3833
Joined: Fri May 28, 2004 5:22 pm

Thu Sep 09, 2004 6:50 pm

icmp is not logged using IP ONLY for some reason, i believe it thinks icmp is not IP protocol but it a different protocol - which it sort of is. Seems like I ran into this as well on 2.8.11. It'd be nice to still be able to specify source / dest IP even when using ALL FRAMES option.

Sam
 
signal
newbie
Topic Author
Posts: 33
Joined: Thu Aug 19, 2004 4:44 am

Thu Sep 09, 2004 7:23 pm

changeip,

The reason its not logged, is because its broke, or its an undocumented feature.

ICMP is most DEFINITELY an IP protocol. In fact, its IP Protocol 1, it is in no way, shape or form not part of the IP protocol: icmp, igmp, tcp, igrp, udp, etc these are all part of IP protocol, and should be caught by sniffer.

Why it is broke, I don't know, but it sure does suck, because I really need to look at ICMP packets on a mikrotik right now.

Brian

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