multicast ping reliability
It s now several times that I run into a strange issue with multicast ping, I am wondering if anyone has witnessed it too and may have an explanation.
When doing a simple multicast ping "ping 220.127.116.11 re 10" (with "ip igmp join-group 18.104.22.168" configured on a receiver), an answer is received for the first ping, then all the subsequent ones timeout. However, simply entering "no ip mroute-cache" on the interfaces of the source direct neighbor (downstream neighbor) fixes the issue.
Why would disabling fast-switching/cef for multicast traffic solve the issue ? And what is the issue in the first place since everything looks like it should work anyway ??