Switch User Manual

IP routing configuration examples 189
3
Init The router received a general hello packet (without
its Router ID) from another router.
4
2-Way The router received a Hello directed to it from
another router. (The hello contains its Router ID)
5
ExStart Indicates the start of the Master/Slave election
process.
6
Exchange Indicates the link state database (LSDB) is
exchanged
7
Loading Indicates the processing state of the LSDB for input
into the routing table. The router can request LSA
for missing or corrupt routes.
8
Full Indicates the normal full adjacency state.
OSPF neighbor state information Neighbor state information can be
accessed by using the show ip ospf neighbor command.
5530-24TFD#show ip ospf neighbor
Interface Nbr Router ID Nbr IP Address Pri State RetransQLen Perm
--------- ------------- -------------- --- ----- ----------- ----
10.1.1.22 1.1.1.1 10.1.1.21 100 Full 0 Dyn
10.1.1.17 1.1.1.5 10.1.1.18 0 Full 0 Dyn
10.1.1.9 1.1.1.4 10.1.1.10 1 Full 0 Dyn
Problems with OSPF occur most often during the initial startup, when the
router cannot form adjacencies with other routers and the state is stuck in
the Init or ExStart/Exchange state.
Init State Problems A router can become stuck in an Init state and not
form adjacencies. There are several possible causes for this problem:
•
Authentication mismatch or configuration problem
•
Area mismatch for Stub or NSSA
•
Area ID mismatch
•
Hello Interval or Dead Interval mismatch
To determine any mismatches in OSPF configuration, use the show ip
ospf ifstats mismatch command.
ExStart/Exchange problems Even though routers can recognize each
other and have moved beyond two way communications, routers can
become stuck in the ExStart/Exchange state.
Nortel Ethernet Routing Switch 5500 Series
Configuration-IP Routing Protocols
NN47200-503 03.01 Standard
5.1 27 August 2007
Copyright © 2005-2007, Nortel Networks
.