Re: Floating static route higher AD BGP - Page 2

Bill19795_2 · ‎02-14-2011

I am setting up a remote site to provide a backup internet circuit for outbound traffic. Everything is working from the main site by redistributing a static route and using default-information originate within BGP to my MPLS provider.

Now on the remote site I setup a static route with an AD of 250 which is higher than the AD of 20 we are getting from the main site over the MPLS network. When the route come up BGP uses the default route from the main site and everything works fine. When I clear the BGP routes at the main site the backup site installs the static route with a higher AD. The problem is when the BGP route comes back up the static route is not getting removed. From looking at some other posts it seems that the redistributed local route is still preferred by BGP. They mentioned setting the weight to 0 in a route map which I tried but I am not getting the results of removing the static route and using the BGP route.

Remote site router config:

router bgp 65011

no synchronization

bgp log-neighbor-changes

network 12.100.1.4 mask 255.255.255.252

network 192.168.2.0

redistribute static route-map redist-static-bgp

neighbor 12.100.1.5 remote-as 1000

neighbor 12.100.1.5 send-community

neighbor 12.100.1.5 weight 40000

default-information originate

no auto-summary

!

ip forward-protocol nd

ip route 0.0.0.0 0.0.0.0 192.168.2.254 250

access-list 10 permit 0.0.0.0

access-list 10 deny any

route-map redist-static-bgp permit 10

match ip address 10

!

Everything working correctly:

Gateway of last resort is 12.100.1.5 to network 0.0.0.0

12.0.0.0/30 is subnetted, 3 subnets

B 12.100.1.0 [20/0] via 12.100.1.5, 00:00:48

C 12.100.1.4 is directly connected, Serial0/0

B 12.100.1.16 [20/0] via 12.100.1.5, 00:00:48

B 192.168.1.0/24 [20/0] via 12.100.1.5, 00:00:48

C 192.168.2.0/24 is directly connected, FastEthernet0/0

B 192.168.3.0/24 [20/0] via 12.100.1.5, 00:00:48

B* 0.0.0.0/0 [20/0] via 12.100.1.5, 00:00:48

RS1R1#show ip bgp

BGP table version is 9, local router ID is 192.168.2.253

Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,

r RIB-failure, S Stale

Origin codes: i - IGP, e - EGP, ? - incomplete

Network Next Hop Metric LocPrf Weight Path

*> 0.0.0.0 12.100.1.5 40000 1000 65010 ?

*> 12.100.1.0/30 12.100.1.5 0 40000 1000 i

r> 12.100.1.4/30 12.100.1.5 0 40000 1000 i

r 0.0.0.0 0 32768 i

*> 12.100.1.16/30 12.100.1.5 0 40000 1000 i

*> 192.168.1.0 12.100.1.5 40000 1000 65010 i

*> 192.168.2.0 0.0.0.0 0 32768 i

*> 192.168.3.0 12.100.1.5 40000 1000 65012 i

RS1R1#

CLEAR IP BGP * :

RS1R1#show ip route

Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP

D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area

N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2

E1 - OSPF external type 1, E2 - OSPF external type 2

i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2

ia - IS-IS inter area, * - candidate default, U - per-user static route

o - ODR, P - periodic downloaded static route

Gateway of last resort is 192.168.2.254 to network 0.0.0.0

12.0.0.0/30 is subnetted, 3 subnets

B 12.100.1.0 [20/0] via 12.100.1.5, 00:03:13

C 12.100.1.4 is directly connected, Serial0/0

B 12.100.1.16 [20/0] via 12.100.1.5, 00:03:13

B 192.168.1.0/24 [20/0] via 12.100.1.5, 00:00:12

C 192.168.2.0/24 is directly connected, FastEthernet0/0

B 192.168.3.0/24 [20/0] via 12.100.1.5, 00:03:13

S* 0.0.0.0/0 [250/0] via 192.168.2.254

RS1R1#show ip bgp

BGP table version is 13, local router ID is 192.168.2.253

Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,

r RIB-failure, S Stale

Origin codes: i - IGP, e - EGP, ? - incomplete

Network Next Hop Metric LocPrf Weight Path

*> 0.0.0.0 192.168.2.254 0 32768 ?

*> 12.100.1.0/30 12.100.1.5 0 40000 1000 i

r> 12.100.1.4/30 12.100.1.5 0 40000 1000 i

r 0.0.0.0 0 32768 i

*> 12.100.1.16/30 12.100.1.5 0 40000 1000 i

*> 192.168.1.0 12.100.1.5 40000 1000 65010 i

*> 192.168.2.0 0.0.0.0 0 32768 i

*> 192.168.3.0 12.100.1.5 40000 1000 65012 i

RS1R1#

milan.kulik · ‎02-17-2011

Hi,

how does

sh ip bgp

output on your HQ router look like after bringing the interface back up?

BR,

Milan

Bill19795_2 · ‎02-17-2011

Posting in a new thread so it does not change the formatting.

b-grace · ‎02-15-2011

So...you're trying to setup a primary and backup path out of your network. Is there any reason you can't build a BGP neighbor from the remotes up to the main (premise) routers. Then you can adjust the weight attribute on the neighbor statements to control preferred routes.

Bill19795_2 · ‎02-17-2011

HQ router with interface 192.168.1.254 up:

BGP table version is 35, local router ID is 192.168.1.253

Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,

r RIB-failure, S Stale

Origin codes: i - IGP, e - EGP, ? - incomplete

Network Next Hop Metric LocPrf Weight Path

*> 0.0.0.0 192.168.1.254 0 32768 ?

r> 12.100.1.0/30 12.100.1.1 0 40000 1000 i

r 0.0.0.0 0 32768 i

*> 12.100.1.4/30 12.100.1.1 0 40000 1000 i

*> 192.168.1.0 0.0.0.0 0 32768 i

*> 192.168.2.0 12.100.1.1 40000 1000 65011 i

HQR1#show ip route

Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP

D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area

N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2

E1 - OSPF external type 1, E2 - OSPF external type 2

i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2

ia - IS-IS inter area, * - candidate default, U - per-user static route

o - ODR, P - periodic downloaded static route

Gateway of last resort is 192.168.1.254 to network 0.0.0.0

12.0.0.0/30 is subnetted, 2 subnets

C 12.100.1.0 is directly connected, Serial0/0

B 12.100.1.4 [20/0] via 12.100.1.1, 00:01:41

C 192.168.1.0/24 is directly connected, FastEthernet0/0

B 192.168.2.0/24 [20/0] via 12.100.1.1, 00:01:41

S* 0.0.0.0/0 [1/0] via 192.168.1.254

HQR1#

MPLS1 router with HQ router sending default route:

MPLS1#show ip route

Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP

D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area

N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2

E1 - OSPF external type 1, E2 - OSPF external type 2

i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2

ia - IS-IS inter area, * - candidate default, U - per-user static route

o - ODR, P - periodic downloaded static route

Gateway of last resort is 12.100.1.2 to network 0.0.0.0

12.0.0.0/30 is subnetted, 2 subnets

C 12.100.1.0 is directly connected, Serial0/0

C 12.100.1.4 is directly connected, Serial0/1

B 192.168.1.0/24 [20/0] via 12.100.1.2, 00:02:37

B 192.168.2.0/24 [20/0] via 12.100.1.6, 16:38:21

B* 0.0.0.0/0 [20/0] via 12.100.1.2, 00:02:37

MPLS1#show ip bgp

BGP table version is 13, local router ID is 12.100.1.17

Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,

r RIB-failure, S Stale

Origin codes: i - IGP, e - EGP, ? - incomplete

Network Next Hop Metric LocPrf Weight Path

*> 0.0.0.0 12.100.1.2 0 0 65010 ?

*> 12.100.1.0/30 0.0.0.0 0 32768 i

*> 12.100.1.4/30 0.0.0.0 0 32768 i

*> 192.168.1.0 12.100.1.2 0 0 65010 i

*> 192.168.2.0 12.100.1.6 0 0 65011 i

MPLS1#show ip bgp 0.0.0.0

BGP routing table entry for 0.0.0.0/0, version 13

Paths: (1 available, best #1, table Default-IP-Routing-Table)

Flag: 0x820

Advertised to update-groups:

1

65010

12.100.1.2 from 12.100.1.2 (192.168.1.253)

Origin incomplete, metric 0, localpref 100, valid, external, best

MPLS1#

HQ Router when interface to 192.168.1.254 goes down:

HQR1#show ip route

Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP

D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area

N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2

E1 - OSPF external type 1, E2 - OSPF external type 2

i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2

ia - IS-IS inter area, * - candidate default, U - per-user static route

o - ODR, P - periodic downloaded static route

Gateway of last resort is 12.100.1.1 to network 0.0.0.0

12.0.0.0/30 is subnetted, 2 subnets

C 12.100.1.0 is directly connected, Serial0/0

B 12.100.1.4 [20/0] via 12.100.1.1, 00:03:48

C 192.168.1.0/24 is directly connected, FastEthernet0/0

B 192.168.2.0/24 [20/0] via 12.100.1.1, 00:03:48

B* 0.0.0.0/0 [20/0] via 12.100.1.1, 00:00:02

HQR1#show ip bgp

BGP table version is 37, local router ID is 192.168.1.253

Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,

r RIB-failure, S Stale

Origin codes: i - IGP, e - EGP, ? - incomplete

Network Next Hop Metric LocPrf Weight Path

*> 0.0.0.0 12.100.1.1 40000 1000 65011 65011 65011 65011 65011 65011 ?

r> 12.100.1.0/30 12.100.1.1 0 40000 1000 i

r 0.0.0.0 0 32768 i

*> 12.100.1.4/30 12.100.1.1 0 40000 1000 i

*> 192.168.1.0 0.0.0.0 0 32768 i

*> 192.168.2.0 12.100.1.1 40000 1000 65011 i

HQR1#

MPLS1 Router with interface down:

MPLS1#show ip route

Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP

D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area

N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2

E1 - OSPF external type 1, E2 - OSPF external type 2

i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2

ia - IS-IS inter area, * - candidate default, U - per-user static route

o - ODR, P - periodic downloaded static route

Gateway of last resort is 12.100.1.6 to network 0.0.0.0

12.0.0.0/30 is subnetted, 2 subnets

C 12.100.1.0 is directly connected, Serial0/0

C 12.100.1.4 is directly connected, Serial0/1

B 192.168.1.0/24 [20/0] via 12.100.1.2, 00:04:57

B 192.168.2.0/24 [20/0] via 12.100.1.6, 16:40:40

B* 0.0.0.0/0 [20/0] via 12.100.1.6, 00:00:53

MPLS1#show ip bgp

BGP table version is 15, local router ID is 12.100.1.17

Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,

r RIB-failure, S Stale

Origin codes: i - IGP, e - EGP, ? - incomplete

Network Next Hop Metric LocPrf Weight Path

*> 0.0.0.0 12.100.1.6 0 0 65011 65011 65011 65011 65011 65011 ?

*> 12.100.1.0/30 0.0.0.0 0 32768 i

*> 12.100.1.4/30 0.0.0.0 0 32768 i

*> 192.168.1.0 12.100.1.2 0 0 65010 i

*> 192.168.2.0 12.100.1.6 0 0 65011 i

MPLS1#show ip bgp 0.0.0.0

BGP routing table entry for 0.0.0.0/0, version 15

Paths: (1 available, best #1, table Default-IP-Routing-Table)

Flag: 0x820

Advertised to update-groups:

1

65011 65011 65011 65011 65011 65011

12.100.1.6 from 12.100.1.6 (192.168.2.253)

Origin incomplete, metric 0, localpref 100, valid, external, best

MPLS1#

HQ Router when interface is back up:

HQR1#show ip route

Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP

D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area

N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2

E1 - OSPF external type 1, E2 - OSPF external type 2

i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2

ia - IS-IS inter area, * - candidate default, U - per-user static route

o - ODR, P - periodic downloaded static route

Gateway of last resort is 192.168.1.254 to network 0.0.0.0

12.0.0.0/30 is subnetted, 2 subnets

C 12.100.1.0 is directly connected, Serial0/0

B 12.100.1.4 [20/0] via 12.100.1.1, 00:07:18

C 192.168.1.0/24 is directly connected, FastEthernet0/0

B 192.168.2.0/24 [20/0] via 12.100.1.1, 00:07:18

S* 0.0.0.0/0 [1/0] via 192.168.1.254

HQR1#show ip bgp

BGP table version is 39, local router ID is 192.168.1.253

Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,

r RIB-failure, S Stale

Origin codes: i - IGP, e - EGP, ? - incomplete

Network Next Hop Metric LocPrf Weight Path

r 0.0.0.0 192.168.1.254 0 32768 ?

r> 12.100.1.1 40000 1000 65011 65011 65011 65011 65011 65011 ?

r> 12.100.1.0/30 12.100.1.1 0 40000 1000 i

r 0.0.0.0 0 32768 i

*> 12.100.1.4/30 12.100.1.1 0 40000 1000 i

*> 192.168.1.0 0.0.0.0 0 32768 i

*> 192.168.2.0 12.100.1.1 40000 1000 65011 i

HQR1#show ip bgp 0.0.0.0

BGP routing table entry for 0.0.0.0/0, version 39

Paths: (2 available, best #2, table Default-IP-Routing-Table, RIB-failure(17))

Not advertised to any peer

Local

192.168.1.254 from 0.0.0.0 (192.168.1.253)

Origin incomplete, metric 0, localpref 100, weight 32768, valid, sourced

1000 65011 65011 65011 65011 65011 65011

12.100.1.1 from 12.100.1.1 (12.100.1.17)

Origin incomplete, localpref 100, weight 40000, valid, external, best

HQR1#

MPLS router when interface is back up, still using RS1 default route:

MPLS1#

MPLS1#show ip route

Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP

D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area

N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2

E1 - OSPF external type 1, E2 - OSPF external type 2

i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2

ia - IS-IS inter area, * - candidate default, U - per-user static route

o - ODR, P - periodic downloaded static route

Gateway of last resort is 12.100.1.6 to network 0.0.0.0

12.0.0.0/30 is subnetted, 2 subnets

C 12.100.1.0 is directly connected, Serial0/0

C 12.100.1.4 is directly connected, Serial0/1

B 192.168.1.0/24 [20/0] via 12.100.1.2, 00:08:37

B 192.168.2.0/24 [20/0] via 12.100.1.6, 16:44:21

B* 0.0.0.0/0 [20/0] via 12.100.1.6, 00:04:34

MPLS1#show ip bgp

BGP table version is 15, local router ID is 12.100.1.17

Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,

r RIB-failure, S Stale

Origin codes: i - IGP, e - EGP, ? - incomplete

Network Next Hop Metric LocPrf Weight Path

*> 0.0.0.0 12.100.1.6 0 0 65011 65011 65011 65011 65011 65011 ?

*> 12.100.1.0/30 0.0.0.0 0 32768 i

*> 12.100.1.4/30 0.0.0.0 0 32768 i

*> 192.168.1.0 12.100.1.2 0 0 65010 i

*> 192.168.2.0 12.100.1.6 0 0 65011 i

MPLS1#show ip bgp 0.0.0.0

BGP routing table entry for 0.0.0.0/0, version 15

Paths: (1 available, best #1, table Default-IP-Routing-Table)

Flag: 0x820

Advertised to update-groups:

1

65011 65011 65011 65011 65011 65011

12.100.1.6 from 12.100.1.6 (192.168.2.253)

Origin incomplete, metric 0, localpref 100, valid, external, best

MPLS1#

Shut / no shut MPLS interface on HQ router:

HQR1#

*Mar 1 16:49:49.383: %SYS-5-CONFIG_I: Configured from console by consoleshow ip route

Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP

D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area

N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2

E1 - OSPF external type 1, E2 - OSPF external type 2

i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2

ia - IS-IS inter area, * - candidate default, U - per-user static route

o - ODR, P - periodic downloaded static route

Gateway of last resort is 192.168.1.254 to network 0.0.0.0

12.0.0.0/30 is subnetted, 2 subnets

C 12.100.1.0 is directly connected, Serial0/0

B 12.100.1.4 [20/0] via 12.100.1.1, 00:00:46

C 192.168.1.0/24 is directly connected, FastEthernet0/0

B 192.168.2.0/24 [20/0] via 12.100.1.1, 00:00:46

S* 0.0.0.0/0 [1/0] via 192.168.1.254

HQR1#show ip bgp

BGP table version is 49, local router ID is 192.168.1.253

Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,

r RIB-failure, S Stale

Origin codes: i - IGP, e - EGP, ? - incomplete

Network Next Hop Metric LocPrf Weight Path

*> 0.0.0.0 192.168.1.254 0 32768 ?

r> 12.100.1.0/30 12.100.1.1 0 40000 1000 i

r 0.0.0.0 0 32768 i

*> 12.100.1.4/30 12.100.1.1 0 40000 1000 i

*> 192.168.1.0 0.0.0.0 0 32768 i

*> 192.168.2.0 12.100.1.1 40000 1000 65011 i

HQR1#show ip bgp 0.0.0.0

BGP routing table entry for 0.0.0.0/0, version 40

Paths: (1 available, best #1, table Default-IP-Routing-Table)

Advertised to update-groups:

1

Local

192.168.1.254 from 0.0.0.0 (192.168.1.253)

Origin incomplete, metric 0, localpref 100, weight 32768, valid, sourced, best

HQR1#

MPLS Router after shut / no shut

MPLS1#show ip route

Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP

D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area

N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2

E1 - OSPF external type 1, E2 - OSPF external type 2

i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2

ia - IS-IS inter area, * - candidate default, U - per-user static route

o - ODR, P - periodic downloaded static route

Gateway of last resort is 12.100.1.2 to network 0.0.0.0

12.0.0.0/30 is subnetted, 2 subnets

C 12.100.1.0 is directly connected, Serial0/0

C 12.100.1.4 is directly connected, Serial0/1

B 192.168.1.0/24 [20/0] via 12.100.1.2, 00:01:52

B 192.168.2.0/24 [20/0] via 12.100.1.6, 16:47:47

B* 0.0.0.0/0 [20/0] via 12.100.1.2, 00:01:52

MPLS1#show ip bgp

BGP table version is 18, local router ID is 12.100.1.17

Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,

r RIB-failure, S Stale

Origin codes: i - IGP, e - EGP, ? - incomplete

Network Next Hop Metric LocPrf Weight Path

*> 0.0.0.0 12.100.1.2 0 0 65010 ?

*> 12.100.1.0/30 0.0.0.0 0 32768 i

*> 12.100.1.4/30 0.0.0.0 0 32768 i

*> 192.168.1.0 12.100.1.2 0 0 65010 i

*> 192.168.2.0 12.100.1.6 0 0 65011 i

MPLS1#show ip bgp 0.0.0.0

BGP routing table entry for 0.0.0.0/0, version 18

Paths: (1 available, best #1, table Default-IP-Routing-Table)

Flag: 0x820

Advertised to update-groups:

1

65010

12.100.1.2 from 12.100.1.2 (192.168.1.253)

Origin incomplete, metric 0, localpref 100, valid, external, best

MPLS1#

milan.kulik · ‎02-17-2011

Hi,

I see you are using weight=40000 for prefixes received from the MPLS neighbor in your HQ.

Which means: When the interface 192.168.1.254 goes up again, the BGP process running on your HQ router inserts the static route to the BGP table with weight 32768..

But as there was also the default route received from the MPLS neighbor in the meantime with weight=40000, it remains the best!

You can see that from your output:

HQR1#show ip bgp

BGP table version is 39, local router ID is 192.168.1.253

Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,

r RIB-failure, S Stale

Origin codes: i - IGP, e - EGP, ? - incomplete

Network Next Hop Metric LocPrf Weight Path

r 0.0.0.0 192.168.1.254 0 32768 ?

r> 12.100.1.1 40000 1000 65011 65011 65011 65011 65011 65011 ?
...

Generally, playing with these preferences needs careful analysis: You need to think "what happens, when the prefix comes first from this direction and what about when it comes first from the other direction,...".

That explains what happens when you shutdown the interface connecting your HQ router to the MPLS neighbor:

The BGP table clears totally, the static routes gets inserted to the BGP database on your HQ router and when the BGP peering starts with the MPLS neighbor, the HQ router advertises the default route to the MPLS. As it has a shorter AS_PATH, it beats the default route received from the remote site and everything is OK again.

So IMHO, you need to decrease the weight assigned to the default route received from your MPLS neighbor in the HQ and everything should start working.

Just be careful not to break anything else - I don't see the reason why you are preferring the routes received from your neighbor here.

Notice there is an exactly opposite request here in the HQ comparing to what you want on the remote site: When a locally originated default route exists in HQ, it should beat the one received from your backbone!

HTH,

Milan

Kishore Chennupati · ‎02-18-2011

Hi Bill,

Looking at the Remote Router and HQ config. the key thing that I see is WEIGHT. Both the Remote and HQ routers are setting the weight to 40000 to the routes from the PE Router. So, any locally originated route for the same route (in this case 0.0.0.0/0) will not preferred since it has a value of 32768. But again as Milan mentioned that which router installs the route first can create some confusion.

Also, from your diagram, I can see that you have only one wan link from the HQR1 and Remote router RSR1 into the cloud. So, is there a reason why you want to use WEIGHT attribute? I mean you are not dual homed and weight is local to the router or am I missing anything here. In my opinion the simplest way to advertise same routes from 2 locations is by AS_PATH prepending from the secondary site which makes it least preferred unless you are not tampering the weight, local pref...

Would I be right in saying this Milan?

Regards,

milan.kulik · ‎02-18-2011

Hi Kishore,

I'd agree with one exception:

If you leave the default values of the weight attribute everywhere, the remote site would never accept the default route coming from the MPLS backbone while having a default static route redistributed to BGP at the same time.

(As locally originated prefixes are getting the weight of 32768 by default.)

That's why I recommended to set the weight of the default route to 0 on the remote site when redistributed to BGP (and also to decrease the local preference.).

In the HQ it would be OK to leave the weight default values.

(Or, to make the current configs working with minimum of changes, just increase the weight of the default route to 50000 when redistributed from static to BGP in the HQ router - using similar route maps as on the remote site.)

BR,

Milan

Bill19795_2 · ‎02-18-2011

Everything is working now. I will post the configurations Monday. Thanks for your help. I ended up using a route map

on the HQ side to set the default route I recive from the MPLS to less then 40000.

Also the reason I set the weight to 40000 on routes received from the neighbor is I have two MPLS providers in two separate routers and I am running EIGRP internally and if I don't set the weight to 40000 I end up using the EIGRP routes and causing a routing loop.

Kishore Chennupati · ‎02-18-2011

Hi Milan

(As locally originated prefixes are getting the weight of 32768 by default.)

That's why I recommended to set the weight of the default route to 0 on the remote site when redistributed to BGP (and also to decrease the local preference.).

I agree with you on this completely..:-)

Bill19795_2 · ‎02-21-2011

So here is the working configuration. Please look it over and let me know if you see a reason why this shouldn't work.

HQR1

track 1 rtr 1 reachability

!

router eigrp 100
redistribute bgp 65010
network 192.168.1.0
default-metric 1000000 100 250 100 1500
no auto-summary
!
router bgp 65010
no synchronization
bgp log-neighbor-changes
network 12.100.1.0 mask 255.255.255.252
network 192.168.1.0
redistribute static route-map redist-static-bgp
redistribute eigrp 100 route-map redist-eigrp-bgp
neighbor 12.100.1.1 remote-as 1000
neighbor 12.100.1.1 route-map MPLS1 in
default-information originate
no auto-summary
!
ip route 0.0.0.0 0.0.0.0 192.168.1.254 track 1
!
!
ip http server
no ip http secure-server
!
ip sla 1
icmp-echo 192.168.1.254 source-interface FastEthernet0/0
timeout 1000
frequency 3
ip sla schedule 1 life forever start-time now
access-list 10 permit 0.0.0.0
access-list 10 deny any
access-list 20 deny any
access-list 30 permit 0.0.0.0
access-list 31 permit any
!
!
!
route-map redist-eigrp-bgp permit 10
match ip address 20
!
route-map MPLS1 permit 10
match ip address 30
set weight 32768
!
route-map MPLS1 permit 20
match ip address 31
set weight 40000
!
route-map redist-static-bgp permit 10
match ip address 10
!
!

RS1

router bgp 65011
no synchronization
bgp log-neighbor-changes
network 12.100.1.4 mask 255.255.255.252
network 192.168.2.0
redistribute static route-map redist-static-bgp
neighbor 12.100.1.5 remote-as 1000
neighbor 12.100.1.5 send-community
neighbor 12.100.1.5 weight 40000
neighbor 12.100.1.5 route-map prep-default out
default-information originate
no auto-summary
!
ip route 0.0.0.0 0.0.0.0 192.168.2.254 250
!
!
ip http server
no ip http secure-server
!
access-list 10 permit 0.0.0.0
access-list 10 deny   any
access-list 20 permit 0.0.0.0
access-list 20 deny   any
!
!
!
route-map redist-eigrp-bgp permit 10
match ip address 20
!
route-map prep-default permit 10
match ip address 10
set community 65536050
!
route-map prep-default permit 20
!
route-map redist-static-bgp permit 10
match ip address 10
set local-preference 90
set weight 0