I am not sure to understand well how keepalives work on Ethernet interfaces.
I indeed would like to use these packets and the funtionnality which put an interface into "err-disable" state when the interface see a keepalive packet it sent to come back (loopback error).
I made a test with a C3560, creating a physical loop betwwen 2 interfaces, keepalives enabled, loopack detect enabled, but nothing happens.
Another example is a real case where we had a loop, provocated on a hub itself connected on a C2960 with a single physical connection. With the loop on the hub (with no STP), the switch C2960 should see the keepalive packet to come back on itself . What happens actually is that the "loopback error" sometimes occurs immediatly, sometimes never.
Has someone deeper knowledge about keepalives which coul help me to understand that?
I indeed would like to use something more "official" like STP BPDU Guard to detect loop. However, it is not so simple. In my topology, there is a switch A, administrated by myself), and switch B connected to A, but B is administrated by another entity, so I have no control on it. So I can't activate BPDU Guard on the uplink interface. Ideally, the solution todetect a loop that occur on switch B would be to activate BPDU Guardonly to detect my own BPDUs, but it's not possible.
For the moment, I can only use features like stormcontrol to mitigate the effect of the loop on the dowstrem routers which suddenly has to treat plenty of ARP or multicast packets.
We are pleased to announce availability of Beta software for 16.6.3.
16.6.3 will be the second rebuild on the 16.6 release train targeted
towards Catalyst 9500/9400/9300/3850/3650 switching platforms. We are
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Introduction Featured Speakers Luis Espejel is the Telecommunications
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