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Forum Discussion

Mattia_59070's avatar
Mattia_59070
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Sep 13, 2014

F5 LTM Sending ACK to a RST,ACK on its own with only routing+nat configured

Hi, we have seen this strange behavior when troubleshooting a network problem. We have a F5 acting only as router-nat for a particular flow, the LTM has 2 interfaces, the source is in a subnet and we...
BinaryCanary_19's avatar
BinaryCanary_19
Historic F5 Account
Sep 14, 2014

If you are using a Forwarding-IP Virtual server or a FastL4 Virtual server, then the F5 is generally not going to be generating any packets.

 

You should look at the Source MAC of the incoming packet and trace which device is generating it.

 

Mattia_59070's avatar
Mattia_59070
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Sep 14, 2014
Thanks, we use a simple 1 to 1 NAT, not a Forwarding-ip VS,what about this configuration ? In our captures we see those packets only on the server, and the source mac address is the BIA of the last hop router, so in order to view the actual source we must do a SPAN session in frontend VLAN. Thanks