LTM v10 Port Forwarding Problem

Question

I have a VIP config'd to accept port 80 and the members of the pool are set to listen to 8081. The checkboxes for port and address translation are checked.  The config settings are the default settings.

Anything to look for or try?

l4l7_53191 · Answer

This should work without any changes at all - what is the actual problem you're seeing? By default, the BigIP does destination NAT/PAT, so the port translations should look fine if you pull up a capture. 
&nbsp;  
&nbsp; -Matt

l4l7_53191 · Answer

This should work without any changes at all - what is the actual problem you're seeing? By default, the BigIP does destination NAT/PAT, so the port translations should look fine if you pull up a capture. 
&nbsp;  
&nbsp; -Matt

wesweber_98132 · Answer

When you navigate to the VIP address on port 80 you see a "link broken" error.  If you navigate to a pool member IP on port 8081 you see a login page.

Tcpdump shows the syn syn-ack process repeated with each browser refresh  when traffic going through the LTM. When connecting directly to the pool member you see the syn, syn-ack and data.

l4l7_53191 · Answer

Are you seeing the traffic actually pass *through* the LTM  and back in your tcpdump? Is your server pointing to the BigIP floating self-ip as its default route? If not, you may want to try enabling SNAT here. If you're dealing with a port translation issue I'd expect a RST in most cases. From what you describe I don't know if translation is the issue or not... 
&nbsp;  
&nbsp; -Matt

Forum Discussion

LTM v10 Port Forwarding Problem

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