From: afiddler (afiddler@xxxxxxxxx)
Date: Sat Sep 01 2001 - 11:49:33 GMT-3
Here is my note after completing this lab with my study buddy: HTH
In the case study starting on page 241, on local preference, there is no
directive to turn off sychronization. We found that synchronization needed
to be off in order to get the results in the output on p244 and p245.
----- Original Message -----
From: "Michael Wong" <Michael.Wong@nec.com.au>
To: "Groupstudy - CCIELAB (E-mail)" <ccielab@groupstudy.com>
Sent: Saturday, September 01, 2001 2:32 AM
Subject: BGP LOCAL_PREF and Redistribution - Doyle Vol II page 242
> Hi Group
>
> Wondering if anyone out there had issues working on the LOCAL_PREF example
on page 242. The local preference part of the example is fine, however I am
questioning the logic behind the redistribution between IS-IS and BGP.
>
> On Page 245, the book states that BGP should not be redistributed into
IS-IS because it will affect the weight and the routing will not work
properly. I am actually using OSPF instead of IS-IS in this scenario as my
particular router doesn't support IS-IS.
>
> Anyway, I have configured the example exactly as shown in the book. When I
look at Zermatt, I get the following routes ....
>
> BGP table version is 13, local router ID is 172.30.255.254
> Status codes: s suppressed, d damped, h history, * valid, > best, i -
internal
> Origin codes: i - IGP, e - EGP, ? - incomplete
>
> Network Next Hop Metric LocPrf Weight Path
> *> 10.20.0.0/16 10.100.83.1 200 0 100 50 ?
> * i10.30.0.1/32 172.30.255.150 65 100 0 ?
> *> 20.2.0.2 782 32768 ?
> * i20.2.0.0/30 172.30.255.150 128 100 0 ?
> *> 0.0.0.0 0 32768 ?
> * i20.2.0.4/30 172.30.255.150 0 100 0 ?
> *> 20.2.0.2 845 32768 ?
> * i172.16.0.1/32 172.30.255.150 65 100 0 ?
> *> 20.2.0.2 782 32768 ?
> *> 172.17.0.0 10.100.83.1 200 0 100 50 ?
> * i172.18.0.0 172.30.255.150 200 0 100 75 ?
> * i172.29.1.1/32 172.30.255.150 65 100 0 ?
> *> 20.2.0.2 782 32768 ?
> *> 172.29.2.0/24 10.100.83.1 200 0 100 50 ?
> * i172.31.0.1/32 172.30.255.150 65 100 0 ?
> *> 20.2.0.2 782 32768 ?
> * i192.168.2.1/32 172.30.255.150 65 100 0 ?
> *> 20.2.0.2 782 32768 ?
> *> 192.168.50.0 10.100.83.1 200 0 100 50 ?
> * i192.168.75.0 172.30.255.150 200 0 100 75 ?
> * i192.168.100.1/32 172.30.255.150 65 100 0 ?
> *> 20.2.0.2 782 32768 ?
>
> Gateway of last resort is not set
>
> 20.0.0.0/30 is subnetted, 3 subnets
> O 20.2.0.4 [110/128] via 20.2.0.10, 00:03:50, Serial0/0
> C 20.2.0.0 is directly connected, Serial1/1
> C 20.2.0.8 is directly connected, Serial0/0
> B 172.17.0.0/16 [20/0] via 10.100.83.1, 00:00:46
> 172.16.0.0/32 is subnetted, 1 subnets
> O 172.16.0.1 [110/129] via 20.2.0.10, 00:03:50, Serial0/0
> 172.29.0.0/16 is variably subnetted, 2 subnets, 2 masks
> O 172.29.1.1/32 [110/129] via 20.2.0.10, 00:03:50, Serial0/0
> B 172.29.2.0/24 [20/0] via 10.100.83.1, 00:00:47
> 172.31.0.0/32 is subnetted, 1 subnets
> O 172.31.0.1 [110/129] via 20.2.0.10, 00:03:50, Serial0/0
> 172.30.0.0/32 is subnetted, 2 subnets
> C 172.30.255.254 is directly connected, Loopback0
> S 172.30.255.150 is directly connected, Serial0/0
> 10.0.0.0/8 is variably subnetted, 3 subnets, 2 masks
> O 10.30.0.1/32 [110/129] via 20.2.0.10, 00:03:51, Serial0/0
> B 10.20.0.0/16 [20/0] via 10.100.83.1, 00:00:47
> S 10.100.83.1/32 is directly connected, Serial1/0
> B 192.168.50.0/24 [20/0] via 10.100.83.1, 00:00:47
> 192.168.2.0/32 is subnetted, 1 subnets
> O 192.168.2.1 [110/129] via 20.2.0.10, 00:03:51, Serial0/0
> 192.168.100.0/32 is subnetted, 1 subnets
> O 192.168.100.1 [110/129] via 20.2.0.10, 00:03:52, Serial0/0
>
> Notice how the routes to 172.18.0.0 and 192.168.75.0 go to Moritz via
IBGP. However they are not being used and they do not show up in the routing
table. If I redistribute BGP into OSPF, or use "no synchronisation" the
routes appear in the routing table .... As shown below. I get slightly
different results between resdistribution and synchronisation in the IP
route table, but the BGP table tells the story.
>
> BGP table version is 16, local router ID is 172.30.255.254
> Status codes: s suppressed, d damped, h history, * valid, > best, i -
internal
> Origin codes: i - IGP, e - EGP, ? - incomplete
>
> Network Next Hop Metric LocPrf Weight Path
> *> 10.20.0.0/16 10.100.83.1 200 0 100 50 ?
> *> 10.30.0.1/32 20.2.0.2 782 32768 ?
> * i 172.30.255.150 65 100 0 ?
> *> 20.2.0.0/30 0.0.0.0 0 32768 ?
> * i 172.30.255.150 128 100 0 ?
> *> 20.2.0.4/30 20.2.0.2 845 32768 ?
> * i 172.30.255.150 0 100 0 ?
> *> 172.16.0.1/32 20.2.0.2 782 32768 ?
> * i 172.30.255.150 65 100 0 ?
> *> 172.17.0.0 10.100.83.1 200 0 100 50 ?
> *>i172.18.0.0 172.30.255.150 200 0 100 75 ?
> *> 172.29.1.1/32 20.2.0.2 782 32768 ?
> * i 172.30.255.150 65 100 0 ?
> *> 172.29.2.0/24 10.100.83.1 200 0 100 50 ?
> *> 172.31.0.1/32 20.2.0.2 782 32768 ?
> * i 172.30.255.150 65 100 0 ?
> *> 192.168.2.1/32 20.2.0.2 782 32768 ?
> * i 172.30.255.150 65 100 0 ?
> *> 192.168.50.0 10.100.83.1 200 0 100 50 ?
> *>i192.168.75.0 172.30.255.150 200 0 100 75 ?
> *> 192.168.100.1/32 20.2.0.2 782 32768 ?
> * i 172.30.255.150 65 100 0 ?
>
> Gateway of last resort is not set
>
> B 192.168.75.0/24 [200/0] via 172.30.255.150, 00:06:57
> 20.0.0.0/30 is subnetted, 3 subnets
> O 20.2.0.4 [110/128] via 20.2.0.10, 00:12:12, Serial0/0
> C 20.2.0.0 is directly connected, Serial1/1
> C 20.2.0.8 is directly connected, Serial0/0
> B 172.17.0.0/16 [20/0] via 10.100.83.1, 00:06:44
> 172.16.0.0/32 is subnetted, 1 subnets
> O 172.16.0.1 [110/129] via 20.2.0.10, 00:12:12, Serial0/0
> B 172.18.0.0/16 [200/0] via 172.30.255.150, 00:06:57
> 172.29.0.0/16 is variably subnetted, 2 subnets, 2 masks
> O 172.29.1.1/32 [110/129] via 20.2.0.10, 00:12:13, Serial0/0
> B 172.29.2.0/24 [20/0] via 10.100.83.1, 00:06:45
> 172.31.0.0/32 is subnetted, 1 subnets
> O 172.31.0.1 [110/129] via 20.2.0.10, 00:12:15, Serial0/0
> 172.30.0.0/32 is subnetted, 2 subnets
> C 172.30.255.254 is directly connected, Loopback0
> S 172.30.255.150 is directly connected, Serial0/0
> 10.0.0.0/8 is variably subnetted, 3 subnets, 2 masks
> O 10.30.0.1/32 [110/129] via 20.2.0.10, 00:12:15, Serial0/0
> B 10.20.0.0/16 [20/0] via 10.100.83.1, 00:06:47
> S 10.100.83.1/32 is directly connected, Serial1/0
> B 192.168.50.0/24 [20/0] via 10.100.83.1, 00:06:47
> 192.168.2.0/32 is subnetted, 1 subnets
> O 192.168.2.1 [110/129] via 20.2.0.10, 00:12:15, Serial0/0
> 192.168.100.0/32 is subnetted, 1 subnets
> O 192.168.100.1 [110/129] via 20.2.0.10, 00:12:15, Serial0/0
>
>
> Has anyone else come across this problem and managed to get it working
without redistributing into BGP or using no synchronisation. Note: (20.2.0.2
is the link to OSPF)
>
> Thanks ..... MW :)
> **Please read:http://www.groupstudy.com/list/posting.html
**Please read:http://www.groupstudy.com/list/posting.html
This archive was generated by hypermail 2.1.4 : Thu Jun 13 2002 - 10:32:13 GMT-3