Forum Discussion

genseek_32178's avatar
genseek_32178
Icon for Nimbostratus rankNimbostratus
Jun 20, 2012

VIP fails Telnet but responds to ICMP

F5A telnet 10.45.2.10 80 Trying 10.45.2.10...

 

telnet: connect to address 10.45.2.10: No route to host telnet:

 

Unable to connect to remote host: No route to host

 

 

F5A ping 10.45.2.10

 

PING 10.45.2.10 (10.45.2.10 ) 56(84) bytes of data.

 

64 bytes from 10.45.2.10: icmp_seq=1 ttl=255 time=2.77 ms

 

64 bytes from 10.45.2.10: icmp_seq=2 ttl=255 time=0.990 ms

 

 

virtual vs_80 { translate address disable translate service disable pool pool80 destination 10.45.2.10:www ip protocol tcp persist persist80 profiles fastl4_80 {} vlans 80 enable }

 

 

Pool members are showing as - inactive down and not responding to telnet on port 80.

 

 

However, memebrs are pinging from F5.

 

 

Any ideas..what route is missing here when VIP is pinging?
  • Virtual server config is as below..

     

     

    virtual vs_80 { translate address disable translate service disable pool pool80 destination 10.45.2.10:www ip protocol tcp persist persist80 profiles fastl4_80 {} vlans 80 enable }

     

     

    VIP is - 10.42.2.10

     

     

    pool member is - 10.45.2.20, Gwy - 10.45.2.129 ( L3 interface in same vlan on upstream router )

     

     

    as telnet to pool member is not responding on port 80, i tried to use below tcpdump syntax referring to Aaron's link

     

     

    tcpdump -nni 0.0 -X -s0 host 10.45.2.20 and port 80 and host 10.45.2.5 (self ip )

     

     

    to determine if the pool member is responding on port 80...but it ain't ..as there is NO reply coming from the pool member.

     

     

    So, i think, we are seeing correct packet.

     

     

    Can you tell me ...where the mistake is....tcpdump syntax or the vaules i'm using.

     

     

    As i said..this is indeed npath configuration....and a similar configuration is working on another device.

     

  • So, i think, we are seeing correct packet. when running tcpdump, was it user traffic? or was it telnet to pool member port 80 from bigip?

     

     

    if it was telnet, did the pool member accept connection on 10.45.2.20 port 80? it might only accept connection on 10.45.2.10 port 80.

     

     

    can you try to run tcpdump with user traffic?
  • No, it wasn't user traffic.

     

     

    As t mentioned earlier, telnet to pool member 10.45.2.20 and to the VIP 10.45.2.10 on port 80 are both failing.

     

     

    as both the VIP and pool member both are failing response on port 80, tcpdump would also may not capture much. or will it?
  • since it is npath, telnet to 10.45.2.10 from bigip might not be a good test.

     

     

    would it be possible to run tcpdump on user traffic?
  • from external network, too, telnet on VIP and pool member is failing.

     

     

    I will try to run dump on user traffic