Resolving The Wrong Hello Interval Problem; Wrong Dead Interval On An Isl Interface - Cisco MDS 9000 Series Troubleshooting Manual

Troubleshooting FSPF Issues
S e n d c o m m e n t s t o m d s f e e d b a c k - d o c @ c i s c o . c o m .
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Step 4 To determine the value of the Hello timer on the adjacent switch, enter the following command:
NEIGHBOR
switch2# show fspf v 1 interfac fc1/16
The system output looks like this:
no shutdown
NEIGHBOR
switch2# show fspf v 1 interfac fc1/16
FSPF interface fc1/16 in VSAN 1
FSPF routing administrative state is active
Interface cost is 500
Timer intervals configured, Hello 20 s, Dead 80 s, Retransmit 5 s -----1
FSPF State is INIT -----2
Statistics counters :
Number of packets received : LSU
Number of packets transmitted : LSU
Number of times inactivity timer expired for the interface = 0
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Step 5 An alternative to check the hello interval setting is the show run command.
switch1# show run
interface fc1/1
fspf hello-interval 5 vsan 1
no shutdown
The system output looks like this.
switch1# show run
interface fc1/1
no shutdown
This output indicates that the neighbor FSPF hello is set to the default. The default setting does not
display in the output from the show run command.

Resolving the Wrong Hello Interval Problem

The Hello interval must match on both sides of an ISL, so you should change either side to match the
other. Use the default Hello interval unless you are sure you need change it. To change the default Hello
interval, enter the following commands:
ML-88(config)# interface fc 1/16
ML-88(config-if)# fspf hello-interval XX vsan 1

Wrong Dead Interval on an ISL Interface

To identify a mismatch in dead intervals on the two sides of an ISL interface, follow these steps:
Cisco MDS 9000 Family Troubleshooting Guide
4-8
Shows that the hello timer is not set to the default, so you should check the neighbor configuration
to make sure it matches.
Shows that FSPF is not in FULL state, indicating a problem.
Shows that the neighbor FSPF Hello interval is set to the default (20 seconds).
Indicates that FSPF is not in FULL state, indicating a problem.
Chapter 4 Troubleshooting Switch Fabric Level Issues
0 LSA 0 Hello 2 Error packets 1
0 LSA 0 Hello 4
OL-5183-02, Cisco MDS SAN-OS Release 1.3
Retransmitted LSU 0