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Tosin_Omojola's avatar
Tosin_Omojola
Icon for Altostratus rankAltostratus
Jan 12, 2015

Default Route Failure

Hi, Please I need assistance with this issue. I created a default route of 0.0.0.0/24 to 10.221.75.2 but traffic is not being directed to the. However, a route of 4.2.2.2 forwarded traffic to the same IP. What might the problem be? My colleague asked if F5 understands route 0.0.0.0?? Please I need this urgently. Thank you

 

6 Replies

  • nathe's avatar
    nathe
    Icon for Cirrocumulus rankCirrocumulus

    You can't have 0.0.0.0/24 as a route as that would mean IPs of 0.0.0.1-254??

     

    If you want a default route you want 0.0.0.0/0.

     

    See if that works.

     

    N

     

  • Hi Sadorect, how did you create the route?

     

    Please run "tmsh list net route" and check for a default route.

     

    It should be honored both for traffic initiated by the F5 i.e. for monitoring real servers and to forward traffic to i.e. to not locally attached poolmembers or by virtual servers in forwarding mode.

     

    Thanks, Stephan

     

  • Please I have another situation here. this case involves a link controller. F5 sits between two networks A and B A is the ISP network subnet and B is the internal network F5 could ping both A and B as well as the internet successively and it could also ping the internal network.

     

    However, both networks A and B could not reach eachother even though there are routes defined on F5 to allow that. The default-gateway-route even specifies the direction for packets, yet, these two aren't getting to eachother but they can both ping F5 in the middle.

     

    i have a listener defined for both networks with the IPs assigned to their respective interfaces, both for UDP and TCP...it's still a no no....

     

    Please help!

     

    Thank you What might the problem be please?

     

  • Please I have another situation here. this case involves a link controller. F5 sits between two networks A and B A is the ISP network subnet and B is the internal network F5 could ping both A and B as well as the internet successively and it could also ping the internal network.

     

    However, both networks A and B could not reach eachother even though there are routes defined on F5 to allow that. The default-gateway-route even specifies the direction for packets, yet, these two aren't getting to eachother but they can both ping F5 in the middle.

     

    i have a listener defined for both networks with the IPs assigned to their respective interfaces, both for UDP and TCP...it's still a no no....

     

    Please help!

     

    Thank you What might the problem be please?

     

  • Hi Sadorect,

    as "listener" you have network virtual servers in IP forwarding mode?

    The easiest approach would be to create a wildcard virtual server of type network 0.0.0.0/0:any for all protocols in mode "forwarding IP" with SNAT AutoMap enabled and listening on all VLANs.

    Please make sure to enable SNAT for all protocols in case you want to PING as well.

    You will find this configuration option via WebUI in System››Configuration:Local Traffic:General (option "SNAT Packet Forwarding" modified to "All Traffic").

    Alternatively you can use tmsh as well:
    tmsh modify sys db snat.anyipprotocol value enable
    tmsh save sys config  
    

    Thanks, Stephan

  • Hi Sadorect,

    how do you test the functionality?

    To troubleshoot it would help to run a tcpdump on the system to look after incoming (and perhaps outgoing traffic).
    tcpdump -e -nnni 0.0:nnnp -s 0 -c 100 host    
    

    The trace should show the incoming packets (including MAC addresses and VLAN information) and the related forwarded traffic (including MAC addresses and VLAN information as well).

    What is the output of the following commands, please:
    tmsh list net self one-line  
    tmsh list net route one-line  
    tmsh list ltm virtual one-line  
    

    Can you ping the router specified as next hop for your default gateway?

    Thanks, Stephan