Troubleshooting Fx Port Connectivity; Fx Port Fails To Achieve Up State; Fcot Is Not Present - 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 .
In the example, VSAN 7 is up, while two VSANs are isolated (VSAN 1 and 8, the first one because of
domain ID misconfiguration, and the second one because of VSAN misconfiguration).

Troubleshooting Fx Port Connectivity

This section describes how to troubleshoot problems with a switch interface in fabric mode (F port). An
F port may be connected to a single N port, which is the mode used by peripheral devices (hosts or
storage).
Two different major scenarios can be recognized in all the possible cases an administrator can incur in
troubleshooting an Fx port:
•
•

Fx Port Fails to Achieve Up State

This section describes the troubleshooting steps to follow if, after connecting an N port to the switch,
the port does not go into the up state.
In order for an Fx port to come up on a switch, the switch port must first acquire bit and word
synchronization with the N port, and receive the FLOGI issued by the connected N port.
If any one of these steps does not occur, the switch port will not come up as an F port.
One of the first steps in troubleshooting an F port not coming up is to issue the show interface command
from the CLI. This tells you where the process of interface initialization stops, and which steps to be
used to solve the problem.
The following examples show different states of the interface, as displayed by the show interface
command. In the examples, note the description of the problem that is printed immediately after the
operational state of the interface.

FCOT Is Not Present

In the example below, the state of the interface is (Fcot is not present). This indicates that the switch does
not detect the presence of an SFP on the interface. If this is the case verify that the SFP on the interface
is seated properly. If reseating the SFP does not resolve the issue, replace the SFP or try another port on
the switch.
switch# show interface fc7/31
c7/31 is down (Fcot not present)
f
OL-5183-02, Cisco MDS SAN-OS Release 1.3
The port doesn't come up (just check the configuration of the interface, the cabling and the port
connected to the switch).
The port comes up, but the host is not able to communicate with the storage subsystem (in this case
the configuration of VSAN and zones need to be checked)
Hardware is Fibre Channel
Port WWN is 21:9f:00:05:30:00:18:a2
Admin port mode is auto, trunk mode is on
vsan is 1
Beacon is turned off
Counter Values (current):
0 frames input, 0 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
Troubleshooting Fx Port Connectivity
Cisco MDS 9000 Family Troubleshooting Guide
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