ISIS questions

Experts,
1) if ISIS on ethernet interfaces uses 802.2 LLC encapsulation
(DSAP=SSAP=0xFE), it means that it has length field in the header so it
can not put on the wire frames longer than 1535 bytes. This means that
even if I can have big MTU on the inteface, ISIS can only use the max
allowed by 802.2 which is roughly ~1500 bytes and then fragment the
LSP ?

2) if I configure 'metric-style transition' both narrow and wide metrics
are used in parallel, but which one will determine the route selection
in case they are in disagreement?

3) are TLVs 128 and 130 still advertised if I configure wide metric only
and therefore I use TLV 135?

4) according to :
http://www.cisco.com/en/US/partner/docs/ios/12_2t/ip_route/command/reference/p2ftisis.html#wp1057284
The command 'default-information originate [route-map map-name]' without
a route map, the default is advertised only in Level 2 LSPs.
I want a L1 only router to advertise the 0/0 in its area but no luck;
this is the config but no default is advertised .....

pe1#show running-config | b ^router isis
router isis A1
 net 49.0001.0000.0000.0002.00
 is-type level-1
 passive-interface Loopback0
 default-information originate route-map LUCA
!
ip route 0.0.0.0 0.0.0.0 Null0
!
access-list 1 permit 1.0.0.2
!
route-map LUCA permit 10
 match ip address 1

pe1#show ip route
<...>
Gateway of last resort is 0.0.0.0 to network 0.0.0.0
<...>
<...>
S* 0.0.0.0/0 is directly connected, Null0

Thanks,
Bit.

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Received on Sun Apr 11 2010 - 21:42:22 ART