•
reuse
: the range is from 1 to 20000. This number is compared to the flapping route’s Penalty value. If the Penalty value is less than
the reuse value, the flapping route is once again advertised (or no longer suppressed). The default is
750
.
•
suppress
: the range is from 1 to 20000. This number is compared to the flapping route’s Penalty value. If the Penalty value is
greater than the suppress value, the flapping route is no longer advertised (that is, it is suppressed). The default is
2000
.
•
max-suppress-time
: the range is from 1 to 255. The maximum number of minutes a route can be suppressed. The default is
four times the half-life value. The default is
60 minutes
.
•
Clear all information or only information on a specific route.
EXEC Privilege
clear ip bgp [vrf
vrf-name
] dampening [
ip-address mask
]
•
View all flap statistics or for specific routes meeting the following criteria.
EXEC or EXEC Privilege mode
show ip bgp [vrf
vrf-name
] flap-statistics [
ip-address
[
mask
]] [filter-list
as-path-name
]
[regexp
regular-expression
]
•
ip-address
[
mask
]
: enter the IP address and mask.
•
filter-list
as-path-name
: enter the name of an AS-PATH ACL.
•
regexp
regular-expression
: enter a regular express to match on.
By default, the path selection in Dell Networking OS is deterministic, that is, paths are compared irrespective of the order of their
arrival. You can change the path selection method to non-deterministic, that is, paths are compared in the order in which they arrived
(starting with the most recent). Furthermore, in non-deterministic mode, the software may not compare MED attributes though the
paths are from the same AS.
•
Change the best path selection method to non-deterministic.
Change the best path selection method to non-deterministic.
CONFIG-ROUTER-BGP mode
bgp non-deterministic-med
NOTE:
When you change the best path selection method, path selection for existing paths remains unchanged until you
reset it by entering the
clear ip bgp
command in EXEC Privilege mode.
Examples of Configuring a Route and Viewing the Number of Dampened Routes
To view the BGP configuration, use the
show config
command in CONFIGURATION ROUTER BGP mode or the
show running-
config bgp
command in EXEC Privilege mode.
The following example shows how to configure values to reuse or restart a route. In the following example,
default = 15
is the set time
before the value decrements,
bgp dampening 2 ?
is the set re-advertise value,
bgp dampening 2 2000 ?
is the suppress value,
and
bgp dampening 2 2000 3000 ?
is the time to suppress a route. Default values are also shown.
Dell(conf-router_bgp)#bgp dampening ?
<1-45> Half-life time for the penalty (
default = 15
)
route-map Route-map to specify criteria for dampening
<cr>
Dell(conf-router_bgp)#
bgp dampening 2 ?
<1-20000> Value to start reusing a route (default = 750)
Dell(conf-router_bgp)#
bgp dampening 2 2000 ?
<1-20000> Value to start suppressing a route (default = 2000)
Dell(conf-router_bgp)#
bgp dampening 2 2000 3000 ?
<1-255> Maximum duration to suppress a stable route (default = 60)
Dell(conf-router_bgp)#bgp dampening 2 2000 3000 10 ?
route-map Route-map to specify criteria for dampening
<cr>
To view a count of dampened routes, history routes, and penalized routes when you enable route dampening, look at the seventh line of the
show ip bgp summary
command output, as shown in the following example (bold).
Dell>show ip bgp summary
BGP router identifier 10.114.8.131, local AS number 65515
Border Gateway Protocol IPv4 (BGPv4)
211
Summary of Contents for S3048-ON
Page 1: ...Dell Configuration Guide for the S3048 ON System 9 11 2 5 ...
Page 137: ...0 Gi 1 1 Gi 1 2 rx Flow N A N A 0 0 No N A N A yes Access Control Lists ACLs 137 ...
Page 142: ...Figure 10 BFD Three Way Handshake State Changes 142 Bidirectional Forwarding Detection BFD ...
Page 241: ...Dell Control Plane Policing CoPP 241 ...
Page 287: ... RPM Synchronization GARP VLAN Registration Protocol GVRP 287 ...
Page 428: ...Figure 53 Inspecting the LAG Configuration 428 Link Aggregation Control Protocol LACP ...
Page 477: ...Figure 73 Configuring Interfaces for MSDP Multicast Source Discovery Protocol MSDP 477 ...
Page 478: ...Figure 74 Configuring OSPF and BGP for MSDP 478 Multicast Source Discovery Protocol MSDP ...
Page 483: ...Figure 77 MSDP Default Peer Scenario 2 Multicast Source Discovery Protocol MSDP 483 ...
Page 484: ...Figure 78 MSDP Default Peer Scenario 3 484 Multicast Source Discovery Protocol MSDP ...
Page 745: ...Figure 104 Single and Double Tag TPID Match Service Provider Bridging 745 ...
Page 746: ...Figure 105 Single and Double Tag First byte TPID Match 746 Service Provider Bridging ...