From: VAUTRIN Olivier (olivier.vautrin@xxxxxxxx)
Date: Sat Nov 03 2001 - 20:24:01 GMT-3
Hello Everybody,
Someone told me that only the OSPF DR (in a frame-relay network) can be
configured for OSPF on demand. I would like to have some info about it.
I tried a lab with 3 routers linked by Frame-relay like this:
A-----B
\ /
\ /
C
C is the DR.
A and B have a priority of 0 (so they cannot be DR)
A,B and C are in the backbone area.
A and B are linked by ISDN and you can see at the end of my mail the
configuration of B.
During this lab, the ISDN link was always up.
I got some traces:
with debug ip ospf lsa
and debug dialer packet
00:27:03: OSPF: Generate external LSA 170.10.8.2, mask 255.255.255.255, type
5, age 3600, metric 16777215, seq 0x80000012
00:27:03: %LINK-3-UPDOWN: Interface Virtual-Access2, changed state to down
00:27:03: OSPF: Sending update on BRI0 to 224.0.0.5
00:27:03: OSPF: Send Type 5, LSID 170.10.8.2, Adv rtr 170.10.4.3, age 3600,
seq 0x80000012 <--------?????
00:27:03: BRI0: ip (s=170.10.8.3, d=224.0.0.5), 84 bytes, outgoing
interesting (ip PERMIT)
00:27:03: BRI0: sending broadcast to ip 170.10.8.2 -- failed, not connected
00:27:03: OSPF: Sending update on Serial0 to 0.0.0.3
00:27:03: OSPF: Send Type 5, LSID 170.10.8.2, Adv rtr 170.10.4.3, age 3600,
seq 0x80000012
00:27:03: OSPF: received update from 170.10.9.5, Serial0
00:27:03: OSPF: Rcv Update Type 5, LSID 170.10.8.2, Adv rtr 170.10.4.3, age
3600, seq 0x80000012
00:27:03: Mask /32
00:27:03: OSPF: Received same lsa
00:27:03: Remove LSA from retransmission list
00:27:03: OSPF: received update from 170.10.9.5, Serial0
So, I am receiving Type 5 LSA all the time. How is it possible??
There is no topology change in my network as you can see with the fabulous
command "show ip ospf stat":
RouterB#sh ip ospf stat
Area 0: SPF algorithm executed 10 times
SPF calculation time
Delta T Intra D-Intra Summ D-Summ Ext D-Ext Total Reason
00:42:33 0 0 0 0 0 0 4 R,
00:41:41 0 0 4 0 8 0 12 R, N, X
00:41:31 4 0 12 0 16 0 36 R, SN, X
00:41:09 4 0 8 0 16 0 28 R, N,
00:40:59 4 0 8 0 24 0 40 R, X
00:39:07 4 0 8 0 20 0 36 R,
00:36:55 4 0 8 0 24 0 36 R,
00:36:45 4 0 12 0 20 0 36 R,
00:18:27 4 0 8 0 20 0 32 R,
00:18:17 4 0 8 0 20 0 36 R, <-----
and so a long time ago
Any ideas?
Cheers,
Olivier Vautrin.
RouterB#s
Building configuration...
Current configuration:
!
version 11.3
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname RouterB
!
enable secret 5 $1$4SQN$zLchrcsPGPJF0okQq45y61
!
ip subnet-zero
no ip domain-lookup
isdn switch-type basic-net3
!
!
!
!
process-max-time 200
!
interface Loopback0
ip address 170.10.4.3 255.255.255.0
!
interface Ethernet0
no ip address
shutdown
!
interface Serial0
ip address 170.10.7.3 255.255.255.240
encapsulation frame-relay
ip ospf priority 0
no ip mroute-cache
bandwidth 800
no fair-queue
frame-relay map ip 170.10.7.2 300 broadcast
!
interface Serial1
ip address 170.10.3.3 255.255.255.0
bandwidth 800
!
interface BRI0
ip address 170.10.8.3 255.255.255.0
encapsulation ppp
ip ospf demand-circuit
bandwidth 128
dialer map ip 170.10.8.2 name RouterA broadcast 1005
dialer load-threshold 1 outbound
dialer-group 1
isdn switch-type basic-net3
ppp multilink
hold-queue 75 in
!
router ospf 1
summary-address 170.10.7.0 255.255.255.0
redistribute rip subnets
redistribute bgp 200 subnets
network 170.10.7.3 0.0.0.0 area 0
network 170.10.8.3 0.0.0.0 area 0
distance 130
!
router rip
redistribute ospf 1 metric 1
redistribute bgp 200 metric 1
passive-interface BRI0
passive-interface Serial0
network 170.10.0.0
distance 140
distance 120 0.0.0.0 255.255.255.255 rip
!
router bgp 200
no synchronization
neighbor 170.10.5.4 remote-as 200
neighbor 170.10.5.4 update-source Loopback0
no auto-summary
!
ip classless
ip bgp-community new-format
!
!
ip access-list standard rip
permit 170.10.1.0 0.0.0.255
permit 170.10.2.0 0.0.0.255
permit 170.10.5.0 0.0.0.255
dialer-list 1 protocol ip permit
alias exec c conf t
alias exec r show ip route
alias exec s show run
alias exec b sho ip int brief
!
line con 0
exec-timeout 0 0
password c
logging synchronous
line aux 0
exec-timeout 0 0
password c
logging synchronous
line vty 0 4
exec-timeout 0 0
password c
logging synchronous
login
!
end
RouterB#sh ver
Cisco Internetwork Operating System Software
IOS (tm) 2500 Software (C2500-IS56I-L), Version 11.3(11b)T1, RELEASE
SOFTWARE (fc2)
TAC Support: http://www.cisco.com/cgi-bin/ibld/view.pl?i=support
Copyright (c) 1986-2001 by cisco Systems, Inc.
Compiled Thu 08-Mar-01 02:58 by cmong
Image text-base: 0x0303F344, data-base: 0x00001000
ROM: System Bootstrap, Version 5.2(8a), RELEASE SOFTWARE
BOOTFLASH: 3000 Bootstrap Software (IGS-RXBOOT), Version 10.2(8a), RELEASE
SOFTWARE (fc1)
R26 uptime is 45 minutes
System restarted by reload
System image file is "flash:/c2500-is56i-l.113-11b.T1.bin", booted via flash
cisco 2500 (68030) processor (revision F) with 16384K/2048K bytes of memory.
Processor board ID 05269939, with hardware revision 00000000
Bridging software.
X.25 software, Version 3.0.0.
Basic Rate ISDN software, Version 1.1.
1 Ethernet/IEEE 802.3 interface(s)
2 Serial network interface(s)
1 ISDN Basic Rate interface(s)
32K bytes of non-volatile configuration memory.
16384K bytes of processor board System flash (Read ONLY)
Configuration register is 0x2102
This archive was generated by hypermail 2.1.4 : Fri Jun 21 2002 - 06:45:03 GMT-3