Hi,
I am working through an IS-IS configuration in the SYBEX BSCI book. I followed the example configs exactly but my routers can not establish adjacency. Any IS-IS gurus with any ideas?
I don't want to post configs yet as the config from the sample chapter is very straightforward. I'm probably missing a trick.
Thanks
You're not giving any information to go on. How are we supposed to know what you have configured?
MTU mismatch comes first to my mind.I don't know what is in BSCI book, so without seeing what have you configured there are many guesses. Did you configure clns routing? did you configure 'clns routing', is-is routing process with NET, and 'ip router isis' on the interfaces?
'debug isis adj' should give you some idea what might be wrong
Kind regards, iLya
I thought it may be a problem with MTU sizes but the mtu size used by RouterA and RouterB are the same.
OK, here is the scenario and config:
Two routers - RouterA and RouterB connected across a serial interface.
Config for Router A - level 1
---------------------------- RouterA#show run Building configuration...
Current configuration : 640 bytes ! version 12.2 service timestamps debug uptime service timestamps log uptime no service password-encryption ! hostname RouterA ! ! ip subnet-zero ! clns routing ! ! ! interface Ethernet0 ip address 192.168.50.1 255.255.255.0 ip router isis clns router isis no shutdown ! interface Ethernet1 no ip address shutdown ! interface Serial0 no ip address ! interface Serial0.1 ip address 192.168.40.1 255.255.255.0 ip router isis clns router isis ! interface Serial1 no ip address ! router isis net 01.0000.0000.0001.00 is-type level-1 ! ip classless no ip http server ! ! ! line con 0 exec-timeout 0 0 line aux 0 line vty 0 4 login ! end
Config for RouterB - level-1-2
-------------------------- RouterB#show run Building configuration...
Current configuration : 1043 bytes ! version 12.2 service timestamps debug uptime service timestamps log uptime no service password-encryption ! hostname RouterB ! ! ip subnet-zero ! clns routing ! ! ! interface Serial0 no ip address shutdown ! interface Serial1 no ip address clockrate 64000 ! interface Serial1.1 ip address 192.168.30.1 255.255.255.0 ip router isis ! interface Serial2 no ip address clockrate 64000 ! interface Serial2.1 ip address 192.168.40.2 255.255.255.0 ip router isis clns router isis ! router isis net 01.0000.0000.0002.00 ! ip classless no ip http server ! ! ! line con 0 line aux 0 line vty 0 4 login ! end
On RouterA, here is the output of show clns neighbor and debug isis adj: RouterA#show clns neighbor
RouterA#
01:29:09: ISIS-Adj: Sending L1 LAN IIH on Ethernet0, length 1497 01:29:16: ISIS-Adj: Sending serial IIH on Serial0.1, length 1499 01:29:18: ISIS-Adj: Sending L1 LAN IIH on Ethernet0, length 1497 01:29:25: ISIS-Adj: Sending serial IIH on Serial0.1, length 1499 01:29:25: ISIS-Adj: Sending L1 LAN IIH on Ethernet0, length 1497 01:29:33: ISIS-Adj: Sending serial IIH on Serial0.1, length 1499 01:29:35: ISIS-Adj: Sending L1 LAN IIH on Ethernet0, length 1497 01:29:41: ISIS-Adj: Sending serial IIH on Serial0.1, length 1499show clns neighb or 01:29:43: ISIS-Adj: Sending L1 LAN IIH on Ethernet0, length 1497RouterA# RouterA# RouterA# RouterA#show clns int e
01:29:51: ISIS-Adj: Sending serial IIH on Serial0.1, length 1499 0 Ethernet0 is up, line protocol is up Checksums enabled, MTU 1497, Encapsulation SAP ERPDUs enabled, min. interval 10 msec. RDPDUs enabled, min. interval 100 msec., Addr Mask enabled Congestion Experienced bit set at 4 packets CLNS fast switching enabled CLNS SSE switching disabled DEC compatibility mode OFF for this interface Next ESH/ISH in 0 seconds Routing Protocol: IS-IS Circuit Type: level-1-2 Interface number 0x0, local circuit ID 0x1 Level-1 Metric: 10, Priority: 64, Circuit ID: RouterA.01 Number of active level-1 adjacencies: 0 Next IS-IS LAN Level-1 Hello in 7 seconds RouterA#Some debug on RouterB:
01:36:46: ISIS-Adj: Sending serial IIH on Serial2.1, length 1499ug isis a 01:36:49: ISIS-Adj: Sending serial IIH on Serial1.1, length 1499dj IS-IS Adjacency related packets debugging is off RouterB# RouterB#show clns int s2.1 Serial2.1 is up, line protocol is up Checksums enabled, MTU 1500, Encapsulation HDLC ERPDUs enabled, min. interval 10 msec. RDPDUs enabled, min. interval 100 msec., Addr Mask enabled Congestion Experienced bit set at 4 packets CLNS fast switching enabled CLNS SSE switching disabled DEC compatibility mode OFF for this interface Next ESH/ISH in 16 seconds Routing Protocol: IS-IS Circuit Type: level-1-2 Interface number 0x0, local circuit ID 0x100 Level-1 Metric: 10, Priority: 64, Circuit ID: RouterB.00 Number of active level-1 adjacencies: 0 Level-2 Metric: 10, Priority: 64, Circuit ID: RouterB.00 Number of active level-2 adjacencies: 0 Next IS-IS Hello in 2 secondschris wrote:
That won't work with sub-interfaces when main serial interface uses HDLC - the router doesn't know where to deliver packets once they reach the router's main interface. Configure IP directly on the main interface.
Kind regards, iLya
This worked. The example in the book was configured for FRAME-RELAY.
Many Thanks
Charlie Root wrote:
with Frame-relay sub-interfaces surely will work because there is DLCI to distinguish between sub-interfaces.
Kind regards, iLya
When using IS-IS with frame relay, you will also have to add a frame relay map for the CLNS protocol for IS-IS to work.
Cisco da Gama
Have you solved it yet?
Xangadib
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