06-26-2018 07:06 AM - edited 03-08-2019 03:29 PM
Guys,
Been a long time but back with a hope of getting some help as usual.
I have a CloudGenix SDWAN device connected to a WS-C4507R+E switch. The CloudGenix has a Controller port which connect to a switchport on the 4500 , port is configured as an access port no special config.
The Controller port non stop sends UDP 3784 BFD packets to its remote DC device as keep alives.These packets are failing and I do not see them even on the access port(applied and ACL to match these packets no logs)
Can't seem to find the correct reason for switch dropping/discarding these packets. Hope someone can help. Attached is the packet capture showing the malformed packets
Thank you in advance !!!
07-31-2018 03:08 AM
There were two issues found
1> CloudGenix BFD process uses port UDP 3784 which is not a standard port for multi hop BFD. FOr multihop BFD the port no is 4784.
2> Cisco 4500E in this case was dropping these packets in TCAM which in itself is a Bug and has been fixed with new releases and provides an option to disable BFD. This prevents inspection of BFD packets and hence the UDP 3784 packets are allowed .
Disable BFD on Cisco IOS with - "feature bfd disable"
On older IOS' there is no work around but to upgrade the IOS and run the above command.
Discover and save your favorite ideas. Come back to expert answers, step-by-step guides, recent topics, and more.
New here? Get started with these tips. How to use Community New member guide