Interface Bouncing Between Offline And Initializing - Cisco MDS 9000 Series Troubleshooting Manual

Chapter 3 Troubleshooting Switch Level Issues and Interswitch Connectivity
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 .
If, on the other hand, just the Rx path to the switch was broken and the TX path was intact, there would be no
bit synchronization. In this case, the switch would not attempt to move to the link initialization stage, and
therefore the OLS & NOS counters would never increment. Some possible causes of the problem could be
a faulty SFP, or a speed mismatch between the Fx port and the Nx port, in case speed autonegotiation is
disabled or doesn't work properly with the specific HBA/Storage port.
One of the first steps in the effort to solve the incompatibility, is to verify the speed configuration on the
switch port. If the switch port is configured for a specific speed, configure the switch port for auto-speed
detection. If the port still does not come up or the speed autonegotiation was already in place, the next
possible step is to statically configure the speed of the port in order to match the one of the Nx port
directly connected.
In case this doesn't solve the issue, and the port stays in the same status, the problem is probably a
physical issue. Verify all physical parts between and including the switch port, the SFP on the switch
port, and if used on the HBA, the HBA itself and the fiber connections.

Interface Bouncing between Offline and Initializing

In the above example, the state of the link bounces between initializing and offline. This indicates that
the link has acquired bit and word synchronization, but has not been able to negotiate the type of link
the switch port needs to become operative (because the initialization failed or an FLOGI is not issued by
the HBAs or the FLOGI has been rejected by the switch).
switch# show interface fc7/2
fc7/2 is down (Initializing)
switch# sh int fc7/2
fc7/2 is down (Offline)
OL-5183-02, Cisco MDS SAN-OS Release 1.3
Hardware is Fibre Channel
Port WWN is 21:82:00:05:30:00:18:a2
Admin port mode is F, trunk mode is on
vsan is 1
Beacon is turned off
Counter Values (current):
143274267 frames input, 182897329172 bytes, 0 discards
0 runts, 0 jabber, 0 too long, 0 too short
0 input errors, 0 CRC, 0 invalid transmission words
0 address id, 0 delimiter
0 EOF abort, 0 fragmented, 0 unknown class
3016111132 frames output, 6029792843852 bytes, 0 discards
Received 14 OLS, 14 LRR, 0 NOS, 31 loop inits
Transmitted 87 OLS, 23 LRR, 65 NOS, 37 loop inits
Counter Values (5 minute averages):
0 frames input, 41 bytes, 0 discards
0 runts, 0 jabber, 0 too long, 0 too short
0 input errors, 0 CRC, 0 invalid transmission words
0 address id, 0 delimiter
0 EOF abort, 0 fragmented, 0 unknown class
0 frames output, 112 bytes, 0 discards
Received 0 OLS, 0 LRR, 0 NOS, 0 loop inits
Transmitted 0 OLS, 0 LRR, 0 NOS, 0 loop inits
Hardware is Fibre Channel
Port WWN is 21:82:00:05:30:00:18:a2
Admin port mode is F, trunk mode is on
vsan is 1
Beacon is turned off
Counter Values (current):
143274267 frames input, 182897329172 bytes, 0 discards
0 runts, 0 jabber, 0 too long, 0 too short
0 input errors, 0 CRC, 0 invalid transmission words
Troubleshooting Fx Port Connectivity
Cisco MDS 9000 Family Troubleshooting Guide
3-15