LTM doing routing - forwarding packets between vlans

On behalf of user Paolo:

Hi so what is happening is my ltm ( all og them ) is doing unexpectedly ( by me ) routing:

[LB:Active:Changes Pending] config  tcpdump -i any  host 173.194.116.100
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode listening on any, link-type EN10MB (Ethernet), capture size 96 bytes
^[[A11:16:03.615517 IP 10.117.161.131.53931 > 173.194.116.100.http: S 2027984805:2027984805(0) win 8192 
11:16:03.615612 IP 10.117.61.12.53931 > 173.194.116.100.http: S 2027984805:2027984805(0) win 8192 

As you can see the packets hit the LB gets to the external interface snatted and then gets out...

If that can be of help i have no forwarding VIPS and i try to lock the sel ips in the internal vlan to none.

Ideas ?

what strikes me is this

net.ipv4.ip_forward = 0