H3C Technologies H3C S12500-X Series Switches - Manual (Page 116)

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Configuring FC tracert
Overview
In an FC SAN, use the fctracert command to obtain bidirectional routing information between source
and destination, and check the network connectivity.
You can use this feature to identify failed nodes and test network connectivity.
FC tracert includes two processes:
• Uplink process—In this process, beginning from the source, each switch along the path to the
destination sends the Switch Trace Route (STR) packet to its next hop until the STR packet reaches the
destination switch. (If the destination of FC tracert is a node, the destination switch refers to the FCF
switch directly connected to the node.) Each switch adds its uplink path information (including its
WWN and domain ID) to the STR packet. After the STR packet reaches the destination switch, the
downlink process starts.
• Downlink process—In this process, beginning from the destination switch, each switch along the
path to the source switch sends the STR packet to its next hop until the STR packet reaches the source
switch. Each switch adds its downlink path information (with the same content as the uplink path
information) to the STR packet. When the source switch receives the STR packet, the FC tracert
process ends. The source outputs information (in the STR packet) about all uplink and downlink
switches along the path.
If an FCF switch fails to forward the STR packet, the switch sets an error reason in the packet and sends
the packet (containing information about switches the packet has passed through) directly to the source
switch.
Figure 32 shows the FC tracert process.
Figure 32 FC tracert flowchart
The following describes the process of an FC tracert operation from Switch A to Switch C.
Source switch
Switch A
Intermediate switch
Switch B
Destination switch
Switch C
STR Request
STR ACC
STR Request
STR ACC
STR Request
STR ACC
STR Request
STR ACC