this is the issue
router isis 100
router isis 100====most people forget sometimes instead of that this is correct for SP ip router ISIS ___!!!
but if you type sh clns ==== clns not enable
especially for troubleshooting
remeber IS-IS uses clns and has IP stack above was usage of clns which most beginers make mistakes they assume by typing router without precidence of ip
when they say read they mean it!!!! as knowldge has no limit and you can never finish all the knowldge on topic there will always be more you dont know or you know but you can do it differently
aspiring to be CCIE SP i dont want to be a statistic just for no its pride that i can do this and its relevant to my job situation been in networking business since 1998