Bays don't crash (at least not in the general case ... for example, mine stayed up this time and the last time this happened), but they do send a NOTIFY and bring down the BGP session, as required by the RFC. (I believe gated does this also.)
In case any Bay Networks users didn't already know this, reasonably new version of the system software have a switch to turn off this behavior: 1:TN]$g wfBgpPeerEntry.41.* wfBgpPeerEntry.wfBgpPeerASLoopDetect.157.130.101.182.157.130.101.181 = 2 wfBgpPeerEntry.wfBgpPeerASLoopDetect.204.70.16.38.204.70.16.37 = 1 wfBgpPeerEntry.wfBgpPeerASLoopDetect.204.70.100.66.204.70.100.65 = 1 wfBgpPeerEntry.wfBgpPeerASLoopDetect.209.54.51.230.209.54.51.229 = 2 wfBgpPeerEntry.wfBgpPeerASLoopDetect.209.54.101.238.209.54.101.237 = 2 [1:TN]$set wfBgpPeerEntry.wfBgpPeerASLoopDetect.204.70.100.66.204.70.100.65 2 (41) (interface) [1:TN]$commit Set this flag to '2' for each interface to keep your router from tearing down BGP sessions when it finds a loop. Don't forget to commit afterwards, and then to do a "save config config" so it will take after you reboot. This has saved our butts several times. ------Scott.