Traceroute on Sophos XG

Hi.

How is possible active traceroute in Sophos XG, in the last models exist one part on activate or desactivate this options but in the XG i don't see any check for this purposal. 

My hosts are reachable from ping but when i launch traceroute always the last hop is sophos and i not view any hop after firewall.

 

  • Traceroute uses ICMP calls to find the hosts.

    https://en.wikipedia.org/wiki/Traceroute

    So basically your Client tries to reach every hop via ICMP. If the last station is XG, it seems like XG is blocking your ICMP requests. Do you have a firewall rule to allow this client to use ICMP ? 

  • In reply to LuCar Toni:

    I remember on v15 or v16 to have the same issue. Depending on the OS you are performing the tests from.

    In my case, Mac OS, traceroute does not work even if I create an ICMP firewall rule at the top.

    Here the tcpdump result:

    19:20:37.858433 Port1, IN: IP 192.168.0.8.33641 > 8.8.8.8.33435: UDP, length 24
    19:20:37.858588 Port1, OUT: IP 192.168.0.1 > 192.168.0.8: ICMP time exceeded in-transit, length 60

    19:20:37.865663 Port1, IN: IP 192.168.0.8.33641 > 8.8.8.8.33436: UDP, length 24
    19:20:37.865805 Port1, OUT: IP 192.168.0.1 > 192.168.0.8: ICMP time exceeded in-transit, length 60
    19:20:37.867118 Port1, IN: IP 192.168.0.8.33641 > 8.8.8.8.33437: UDP, length 24
    19:20:37.867249 Port1, OUT: IP 192.168.0.1 > 192.168.0.8: ICMP time exceeded in-transit, length 60
    19:20:37.868407 Port1, IN: IP 192.168.0.8.33641 > 8.8.8.8.33438: UDP, length 24

  • In reply to lferrara:

    Tried it with Windows, works fine. 

    Could you please create a drppkt of those drops? 

    And which filter for tcpdump did you use? 

  • In reply to lferrara:

    Same here. I hit the XG and from then on *.

    I run the same test on W10 out the same firewall rule and success.

    Ian

  • In reply to LuCar Toni:

    Sent pcap via PM.

    Let us know

  • Hi, thanks for reply. 

    I create one rule permit Info_Address, Info_Request, Ping and IMCP, but ping works correctly and traceroute no. I try from Linux and MacOs computer but the result is the same. 

    I have a sensation that is a problem from a bgp process when the networks are published from Sophos, but not are connected directly. 

    I have to run new tests. 

     

  • In reply to jfmartinez:

    Hi folks,

    then answer appears to be traceroute -I sophos.com on MACs.

    Ian

  • In reply to lferrara:

    I would need the drop packet capture, not a Wireshark Dump. 

  • In reply to LuCar Toni:

    Lucar,

    the tcpdump comes from xg console.

  • In reply to rfcat_vk:

    Ian,

    can you try from Linux box?

    Thanks

  • In reply to lferrara:

    Hi Luk,

    so no linux boxes these days other the Sophos firewall devices,

    Ian

  • In reply to lferrara:

    Hi, 

    I mean drop packet capture, not tcpdump.

    on CLI (advanced shell) simply use 'drppkt' on Console use drop-packet-capture.

    https://community.sophos.com/kb/en-us/127111

    I prefer advanced shell - You can set all filter via Grep (Piping | ) 

  • In reply to rfcat_vk:

    Try adding the following from internal to external

     

    Name TraceRoute
    Type TCP/UDP
    Details UDP (1:65535) / (33434:33534)