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With StackWise-480, once a packet is on the ring, it is guaranteed to be delivered to the destination interface. Add
to this that StackWise-480 rings will dynamically load balance, and you can see that ring congestion is not an issue
on StackWise-480.
Troubleshooting Tips and Operational Details
FlexStack Member Addition
When a new switch joins an existing stack (that is, a stack that has already elected a master), then the new switch
will be rebooted after it joins. This is to remove any old configuration. When the new switch completes the reload, it
will become a member of the existing stack. The new member will be assigned the next available unused member
number if it was not preprovisioned. Preprovisioning of switch members is covered in the Cisco Catalyst 2960-S
and 2960-X software configuration guide on Cisco.com. This behavior is covered in more detail in subsequent
sections.
Details on FlexStack Cables and Connections
Match the keys on the cable with the connector when connecting FlexStack cables. It should slide in easily. When
a good connection is made, there should be a “click” as the cable connects correctly. If it does not slide in easily,
try turning the cable 180 degrees to match the keys on the cable with the connector. The tabs on the cables face
away from each other.
Figure 11 shows a stack with a single bad FlexStack cable or connection (indicated by link B). This stack provides
only half bandwidth and does not have redundant connections. A broken FlexStack link is operationally the same
as not having a FlexStack link.
To see if the stack has a broken or unconnected stack port, use the “show switch stack-ports” command. Stack
port connections for the nonredundant stack shown in Figure 11:
Figure 11. Failed Stack Link
C2960-NonRedundant# show switch stack-ports
Switch # Port 1 Port 2
-------- ------ ------
1 Ok Down
2 Ok Ok
3 Ok Down
C2960-NonRedundant# show switch neighbors
Switch # Port 1 Port 2
-------- ------ ------
1 2 None
2 1 3
3 2 None
Only member 2 (in the middle)
has two active stack
connections.
Member 2 connects to member 1 on port
1 and member 3 on port 2.