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Ria_330222's avatar
Ria_330222
Icon for Nimbostratus rankNimbostratus
Apr 02, 2018
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virtual server responding to an IP but not responding to another source IP but there is no firewall/policy/restrictions coming in picture

hi team,

 

virtual server responding to an IP but not responding to another source IP but there is no firewall/policy/restrictions coming in picture

 

i have applied fast l4 profile and all vlans are allowed for the vip.

 

how can i further troubleshoot? can you suggest if i m missing anything here?

 

while running tcpdump, for the working scenario, f5 vip is sending ack packet to the source ip whereas for non working it is only sending ICMP echo reply.

 

the vip is in port 25.

 

application delivery
BIG-IP
LTM
  • Andy_304337's avatar
    Andy_304337
    Apr 02, 2018

    Well when you say the another source IP is not responding. Can you clarify on the following

     

    1. All source IP are from same subnet ?
    2. Is there snat allowed and what type of snat ?
    3. What type of response is working sending ?

    And when you say the for non working it sending only ICMP echo reply - do you have ICMP ping set as health monitor ?

     

    Did you check the connection table for the VIP ?

     

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  • Andy_304337's avatar
    Andy_304337
    Icon for Cirrus rankCirrus
    Apr 02, 2018

    Well when you say the another source IP is not responding. Can you clarify on the following

     

    1. All source IP are from same subnet ?
    2. Is there snat allowed and what type of snat ?
    3. What type of response is working sending ?

    And when you say the for non working it sending only ICMP echo reply - do you have ICMP ping set as health monitor ?

     

    Did you check the connection table for the VIP ?

     

    • Ria_330222's avatar
      Ria_330222
      Icon for Nimbostratus rankNimbostratus
      Apr 02, 2018
      1. No the source IPs are from different subnet

      2.SNAT is not enabled

       

      3.for the working scenario, VIP IP is sending ack (F) packet to the source server.

       

      Yes icmp is appplied as health monitor.

       

      No havent checked the connection table