10-Aug-2021 01:57
Hi All,
Hope you all are doing great.
I have requirement where my old IP range (SUBNET) is fully exhausted. Now we got new range of ip (Subnet).
So can we configure two subnet (one for old default route (already exist) and one for new subnet) in F5 for same partition. Doing so will have an impact on existing default route ?
Regards,
RAQS
11-Aug-2021 03:01
Hi RAQS,
No, if Auto Last Hop is still enable on you F5 BIG-IP.
K13876: Overview of the Auto Last Hop setting (11.x - 16.x)
Auto Last Hop is a setting that allows the BIG-IP system to track the source MAC address of incoming connections and return traffic from pools to the source MAC address, regardless of the routing table.
Regards
11-Aug-2021 03:17
Hi Lidev,
Thanks for replying. Can you please elaborate your answer "No". Like for it means we can configure two default routes ?
Regards,
Raqs
11-Aug-2021 04:49
No need, please read K article and you see that Auto Last Hop feature allows packets to be routed without interrogating routing table.
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11-Aug-2021 04:53
As of now i am not seeing any traffic on new range VIP. From Network end all routes are in place and rules are in place in firewall. What check or configuration required at F5 end ?
11-Aug-2021 05:24
Have you added a new self-ip (new subnet) on BIG-IP (Network ›› Self IPs) ?
11-Aug-2021 05:28
Nope. At present we have self IP for old subnet only. Haven't configured self ip for new subnet.
11-Aug-2021 06:19
You have to do this new Self IP declaration to ensure that the routing works.
11-Aug-2021 06:42
Thanks for that information. So in that case need to create VLAN also ? which is define for new subnet. Old subnet and new subnet are in different VLAN.
11-Aug-2021 06:58
Yes and tagged the new VLAN on the F5 interface.
11-Aug-2021 07:37
Thanks Lidev for your help and support.Let me try this and i ll update the thread accordingly.
16-Aug-2021 05:12
Hi Lidev,
We created NEW VLAN, and defined new self IP, but still its not working. What can we try ? Or do i miss anything?
16-Aug-2021 06:02
Hi,
If everything seems OK on BIG-IP configuration, you can do a tcpdump on the F5 BIG-IP to identify root cause of the routing issue.
23-Jun-2022 23:51
Hey RAQS ,
Did that work? Did you do any additional steps? I am also looking for a similar solution, your feedback would help me implement better.
Do you have any article/doc that sums up all the steps to do so?
Thanks in advance.