Hello,
I am facing an issue where I loose an isis adjacency between router A and B as soon as we change interface type to point-to-point (when in BROADCAST it is ok) and the 'show clns neighbor' outputs nothing.
The 'debug isis adj-packet' outputs the following when in isis BROADCAST type (isis neighborship UP)
On router A :
ISIS-Adj: Sending L1 LAN IIH on TenGigabitEthernet1/2.10, length 91
ISIS-Adj: Rec L1 IIH from bbbb.bbbb.bbbb (TenGigabitEthernet1/2.10), cir type L1, cir id 0000.0000.0034.01, length 91
On router B :
ISIS-Adj: Rec L1 IIH from aaaa.aaaa.aaaa (TenGigabitEthernet1/2.10), cir type L1, cir id 0000.0000.0034.01, length 91
ISIS-Adj: Sending L1 LAN IIH on TenGigabitEthernet1/2.10, length 91
The 'debug isis adj-packet' outputs the following when in isis POINT-TO-POINT type (isis neighborship DOWN)
On router A :
ISIS-Adj: Sending L1 LAN IIH on TenGigabitEthernet1/2.10, length 9197
ISIS-Adj: Sending serial IIH on TenGigabitEthernet1/2.10, length 9196
ISIS-Adj: Rec L1 IIH from bbbb.bbbb.bbbb (TenGigabitEthernet1/2.10), cir type L1, cir id 0000.0000.0034.01, length 9197
On router B :
ISIS-Adj: Sending L1 LAN IIH on TenGigabitEthernet1/2.630, length 9197
ISIS-Adj: Sending serial IIH on TenGigabitEthernet1/2.10, length 9196
ISIS-Adj: Rec L1 IIH from aaaa.aaaa.aaaa (TenGigabitEthernet1/2.10), cir type L1, cir id 0000.0000.0034.01, length 9197
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Does someone have a clue about the potential cause of this isis adjacency loss when changing isis mode to point-to-point specifically ? Can it be related to MTU ??
Here the config of both interfaces which are the same.
interface TenGigabitEthernet1/2.10
encapsulation dot1Q 630
ip address x.x.x.x x.x.x.x
no ip redirects
no ip unreachables
no ip proxy-arp
ip mtu 9180
ip router isis
ip flow ingress
ip pim sparse-mode
ipv6 address xxxx:xxx:xxxx:xxx:x::x/xx
ipv6 enable
ipv6 mtu 9180
ipv6 router isis
no ipv6 mld router
mpls ip
bfd interval 50 min_rx 50 multiplier 3
no cdp enable
isis metric 30 level-1
isis password <removed>
isis ipv6 metric 30 level-1
( isis network point-to-point )
Any help would be appreciated.
Thanks a lot
Karim
