Perfectly explained with good examples using both wireshark and TCP dump utility. I'm happy to have watched it and I recommend every one to watch this as it's going to be helpful for you if you're a Network Engineer. Thanks Varun for creating such nice videos. Keep coming with more. Kudos! :-)
But, I don't see that you have diagnosed the ERR_CONNECTION_RESET failure seen when trying to access the VIP and the tcpdump command message on bigip [R.] (reset) sent from the VIP to the client. What was the solution?
i have below question if reals server is 192.168. 20.21 and 192.168.20.22 ansd self IP configured for this subnet as 192.168.20.2 and 192.168.20.3 in active standby f5 so it will anyone of the self as client IP when forward the traffic to real server?, since you use comman subnet for all client, VIp, real server hence i have a doubt and asking this question.
Yes, When we use Auto Map configuration for SNAT it will use any self IP assigned to egress VLAN and prefer the floating IP over Non floating self IP address. When there are multiple self IP addresses on the egress VLAN, the BIG-IP system alternates the addresses. Hope this is helpful for you
To add on last comment,In absence of self ip addrees in egress vlan then self ip address of non egress vlan can be used, depending on the network routing configuration, selection of a self IP other than the egress VLAN may cause traffic disruption. F5 recommends that you ensure that you have configured floating self IP addresses on all VLANs from which you expect SNAT traffic to egress. The SNAT Automap feature selects a translation address from the available self IP address in the following order of preference: Floating self IP addresses on the egress VLAN Floating self IP addresses on different VLANs Non-floating self IP addresses on the egress VLAN Non-floating self IP addresses on different VLANs Note: Floating IP is preferred to avoid disruption in HA failover scenario