Cisco access-lists ???
danny at genuity.net
Sat Jun 28 02:35:17 UTC 1997
something like this ("in cisco parlance" :-) should do the trick:
router bgp 65534
bgp dampening route-map damp
access-list 101 permit ip any 255.255.240.0 0.0.15.255
access-list 102 permit ip any any
route-map damp permit 10
match ip address 101
set dampening 30 750 2000 90
route-map damp permit 20
match ip address 102
set dampening 15 750 2000 60
you can see the effects from the output below. in short, i've tightened the
thresholds on prefixes longer than /19.
lab2-7507#sh ip bgp fla
BGP table version is 91081, local router ID is 126.96.36.199
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal
Origin codes: i - IGP, e - EGP, ? - incomplete
Network From Flaps Duration Reuse Path
*d 188.8.131.52 184.108.40.206 4 00:02:35 00:58:30 65533
*d 220.127.116.11/20 18.104.22.168 4 00:02:35 00:58:30 65533
*d 22.214.171.124/16 126.96.36.199 4 00:02:35 00:28:40 65533
we're currently not dampening based on prefix length yet, although we are
experimenting with it.
> The 'discussion' of Jack's report seems to have overwhelmed an actual
> operational question. I am shocked and surprised.
> In cisco parlance, such an entry might be
> access-list 142 deny ip any 255.255.255.128 0.0.0.127
> which blocks any prefix longer than a /24.
> As to how to express the dampening in the report you mention, could someone
> who has it actually installed (come on RV, SD, ...) and debugged please
> post? I have exceeded my error quota for the day. Thanks.
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