Symptom
IOS will crash because of an exception in BGP Scanner or BGP Task process. Similar log is seen:
Exception to IOS Thread:
Frame pointer 0x7F9EAD233AD8, PC = 0x5578358EC0A1
UNIX-EXT-SIGNAL: Segmentation fault(11), Process = BGP Scanner
-Traceback= 1#689ef8c6b8edea6381fd734ec9bf6bb6 :55782BE15000+9AD70A1 :55782BE15000+5346BAE
Conditions
'show ip route' is displaying a BGP learned route at the same time that same route is being withdrawn/uninstalled from RIB.
Workaround
Do not use 'show ip route'.
Further Problem Description
The crash may not occur right when the condition is hit, but it sets up the condition that may cause the router to crash at some later point.
This is a timing issue - one can potentially use 'show ip route' and not trigger any problems. Thus, limiting the usage of 'show ip route' during BGP flaps may reduce the chances of hitting the crash, but it will not eliminate the probability entirely.
This affects all options of 'show ip route'/'show ipv6 route' (including vrf, bgp, and other 'show ip/ipv6 route' options).
Some platforms/versions have a SMU patch available while waiting for the main code release.
