Hi ,
R1(IOS) 920--------------------R2(XR) NCS
Both interfaces configured with MTU 9212 , But ISIS was showing INIT state . After disabling hello padding at both ends it came up.
i have some queries regarding CLNS MTU on XR and IOS devices.
> on IOS device MTU 9212 configured on interface but why CLNS MTU is always less than 3 bytes ?
R1# show run interface TenGigabitEthernet0/0/12 | include mtu
mtu 9212
R1#show clns interface tenGigabitEthernet 0/0/12 | include MTU
Checksums enabled, MTU 9209, Encapsulation SAP
R1#
> on XR device CLNS MTU is 14 byte less than interface MTU
R2: -
Interface TenGigE0/0/0/27, ifh 0x0f000048 (up, 9212)
-------- -----------------
None hw_oor (up, 9212)
None qos_out (up, 9212)
None qos_in (up, 9212)
None ether (up, 9212)
arp arp (up, 9198)
clns clns (up, 9198)
ipv4 ipv4 (up, 9198)
mpls mpls (up, 9198)
ether_sock ether_sock (up, 9198)
> How do we need adjust the MTU on both devices for ISIS to come up with "hello padding" ?
> what would be size of padded hello frames with these MTU settings sent from R1 to R2 and vice-versa ?
