From: ying c (bf5tgh1@yahoo.com)
Date: Sat Sep 28 2002 - 11:38:51 GMT-3
What I'm trying to say is you cannot remove eigrp
summarized null route, see below (after (2)):
Test case:
R1---eigrp---R2
R1: 150.10.2.0/28, 150.10.1.0/24
R2: 150.10.1.0/24
We need no null summarized route in R1,
R2 need to see 150.10.2.0/24 in R2
=======================================
Before - with null summarized route:
R1:
interface Loopback0
ip address 150.10.2.1 255.255.255.240
!
interface Ethernet0
mac-address 0001.0001.0001
ip address 150.10.1.1 255.255.255.0
ip summary-address eigrp 100 150.10.2.0 255.255.255.0
5
!
router eigrp 100
network 150.10.1.0 0.0.0.255
network 150.10.2.0 0.0.0.15
auto-summary
no eigrp log-neighbor-changes
!
r1#sh ip route
Gateway of last resort is not set
150.10.0.0/16 is variably subnetted, 3 subnets, 2
masks
C 150.10.1.0/24 is directly connected, Ethernet0
D 150.10.2.0/24 is a summary, 00:02:29, Null0
<<<<-----
C 150.10.2.0/28 is directly connected, Loopback0
r1#sh ip eigrp top
IP-EIGRP Topology Table for AS(100)/ID(150.10.2.1)
Codes: P - Passive, A - Active, U - Update, Q - Query,
R - Reply,
r - reply Status, s - sia Status
P 150.10.1.0/24, 1 successors, FD is 281600
via Connected, Ethernet0
P 150.10.2.0/24, 1 successors, FD is 128256
via Summary (128256/0), Null0
P 150.10.2.0/28, 1 successors, FD is 128256
via Connected, Loopback0
R2:
!
interface Ethernet0
mac-address 0002.0002.0002
ip address 150.10.1.2 255.255.255.0
!
router eigrp 100
network 150.10.1.0 0.0.0.255
auto-summary
no eigrp log-neighbor-changes
!
r2#sh ip route
Gateway of last resort is not set
150.10.0.0/24 is subnetted, 2 subnets
C 150.10.1.0 is directly connected, Ethernet0
D 150.10.2.0 [90/409600] via 150.10.1.1,
00:04:15, Ethernet0
r2#sh ip eigrp top
IP-EIGRP Topology Table for AS(100)/ID(150.10.1.2)
P 150.10.1.0/24, 1 successors, FD is 281600
via Connected, Ethernet0
P 150.10.2.0/24, 1 successors, FD is 409600
via 150.10.1.1 (409600/128256), Ethernet0
r2#
==================
After (1) with distribute-list 1 in null 0 in R1:
r1#conf t
Enter configuration commands, one per line. End with
CNTL/Z.
r1(config)#router eigrp 100
r1(config-router)#distribute-list 1 in null 0 <<<<----
add the line
r1(config-router)#exit
r1(config)#access-list 1 deny any
r1(config)#^Z
r1#
00:19:44: %SYS-5-CONFIG_I: Configured from console by
console
r1#sh run | begin router eigrp <<<<--- won't stick
router eigrp 100
network 150.10.1.0 0.0.0.255
network 150.10.2.0 0.0.0.15
auto-summary
no eigrp log-neighbor-changes
!
r1#sh ip route
Gateway of last resort is not set
150.10.0.0/16 is variably subnetted, 3 subnets, 2
masks
C 150.10.1.0/24 is directly connected, Ethernet0
D 150.10.2.0/24 is a summary, 00:06:46, Null0
<<<--- Here's Null0 as expected
C 150.10.2.0/28 is directly connected, Loopback0
r1#sh ip eigrp top
IP-EIGRP Topology Table for AS(100)/ID(150.10.2.1)
Codes: P - Passive, A - Active, U - Update, Q - Query,
R - Reply,
r - reply Status, s - sia Status
P 150.10.1.0/24, 1 successors, FD is 281600
via Connected, Ethernet0
P 150.10.2.0/24, 1 successors, FD is 128256
via Summary (128256/0), Null0
P 150.10.2.0/28, 1 successors, FD is 128256
via Connected, Loopback0
r1#
==================================================
After (2) with distribute-list in but remove Null 0:
r1#sh run | begin router eigrp
router eigrp 100
network 150.10.1.0 0.0.0.255
network 150.10.2.0 0.0.0.15
distribute-list prefix no-summ in
auto-summary
no eigrp log-neighbor-changes
!
ip prefix-list no-summ seq 5 deny 150.10.2.0/24
ip prefix-list no-summ seq 10 permit 0.0.0.0/0 le 32
r1#debug ip eigrp
IP-EIGRP Route Events debugging is on
r1#conf t
Enter configuration commands, one per line. End with
CNTL/Z.
r1(config)#int e0
r1(config-if)#shut
r1(config-if)#
00:38:09: %LINK-5-CHANGED: Interface Ethernet0,
changed state to administratively down
00:38:10: %LINEPROTO-5-UPDOWN: Line protocol on
Interface Ethernet0, changed state to down
r1(config-if)#no shut
r1(config-if)#
00:38:21: IP-EIGRP: 150.10.2.0/24 routing table not
updated
00:38:23: %LINK-3-UPDOWN: Interface Ethernet0, changed
state to up
00:38:24: IP-EIGRP: 150.10.2.0/28 - don't advertise
out Ethernet0 <<<<----
00:38:24: IP-EIGRP: 150.10.1.0/24 - do advertise out
Ethernet0
00:38:24: IP-EIGRP: 150.10.2.0/24 - not in IP routing
table <<<<----
00:38:24: %LINEPROTO-5-UPDOWN: Line protocol on
Interface Ethernet0, changed state to up
00:38:26: IP-EIGRP: 150.10.2.0/28 - don't advertise
out Ethernet0
00:38:26: IP-EIGRP: 150.10.1.0/24 - do advertise out
Ethernet0
00:38:26: IP-EIGRP: 150.10.2.0/24 - not in IP routing
table
00:38:27: IP-EIGRP: Processing incoming UPDATE packet
r1(config-if)#^Z
r1#sh ip
00:38:36: %SYS-5-CONFIG_I: Configured from console by
console route
Gateway of last resort is not set
150.10.0.0/16 is variably subnetted, 2 subnets, 2
masks
C 150.10.1.0/24 is directly connected, Ethernet0
C 150.10.2.0/28 is directly connected, Loopback0
r1#sh ip eigrp top
IP-EIGRP Topology Table for AS(100)/ID(150.10.2.1)
P 150.10.1.0/24, 1 successors, FD is 281600
via Connected, Ethernet0
P 150.10.2.0/24, 1 successors, FD is 128256
via Summary (128256/0), Null0
P 150.10.2.0/28, 1 successors, FD is 128256
via Connected, Loopback0
r1#
r2#sh ip route <<<<--- poor r2 is screwed...
Gateway of last resort is not set
150.10.0.0/24 is subnetted, 1 subnets
C 150.10.1.0 is directly connected, Ethernet0
r2#sh ip eigrp top
IP-EIGRP Topology Table for AS(100)/ID(150.10.1.2)
P 150.10.1.0/24, 1 successors, FD is 281600
via Connected, Ethernet0
--- Geoff Zinderdine <geoffz@mts.net> wrote:
> What do you mean it won't take the command? Even
> though it doesn't show in
> the config or survive a reboot, it does nuke the
> route to null0. Do we have
> to worry about it surviving a reboot?
>
This archive was generated by hypermail 2.1.4 : Mon Oct 07 2002 - 07:44:06 GMT-3