Hi Dave, You wrote:
> You didn't ask a question. I was just noting that the > question as to whether or not something is "up" is not > well formed. I did ask a question: >>>> How can an ALT router, such as this busy level 1 >>>> aggregation router, detect the failure or >>>> unreachability of a Map-Server? I guess it would >>>> find out when it tries to send a Map-Request message >>>> to the Map-Server via the GRE tunnel. But is there >>>> a keepalive arrangement so the level 1 router could >>>> detect the disappearance of this Map-Server before >>>> it sends a Map-Request? My question relates to how an ALT router can detect a Map-Server (also an ALT Router, I assume) being "down". You answered this, in part, with your mention of BGP keep-alives in the GRE tunnel between the two devices. I also intended to ask more clearly the same question about how a Map-Server can detect when an ETR is "down". In both cases, "down" means not "up" enough to justify the upstream device continuing to advertise the downstream device's EID on the ALT network. My previous message addressed difficulties I perceive with the Map-Server detecting an ETR being down. I won't repeat that, but there is no GRE tunnel, no TCP-BGP session and so far no protocol for the Map-Server sensing the "down"ness of an ETR and making decisions about when to stop advertising that ETR's EID(s). - Robin _______________________________________________ rrg mailing list [email protected] http://www.irtf.org/mailman/listinfo/rrg
