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Table 2. Allowed Mixed Stack Combinations
Mixed Stack Combination
2960-XR IP Lite
2960-X LAN Base
2960-S LAN Base
2960-XR IP Lite
Yes
No
No
2960-X LAN Base
No
Yes
Yes
2960-S LAN Base
No
Yes
Yes
Table 3 shows FlexStack-Plus backward compatibility and performance of 2960-X and 2960-XR with the 2960-S
switches.
Table 3. Backward Compatibility
Scale of Mixed Stack Combination
Max Stack Bandwidth
Stack Limit
Cisco IOS Software Feature Set
2960-XR IP Lite
80Gbps
8
IP Lite
2960-X LAN Base
80Gbps
8
LAN Base
2960-X, 2960-S LAN Base
40Gbps
4
LAN Base
When the 2960-S and 2960-X members are stacked together, the entire stack (even the 2960-X members) fall
back to FlexStack capabilities. Mixing 2960 members limits the max stack members to four, and 20Gbps stack
bandwidth per member, and 40Gbps per stack.
FlexStack Cabling
Special cables are used to connect Cisco Catalyst 2960 Series Switches together in a stack. These special
FlexStack cables can only be used to stack Cisco Catalyst 2960 switches with other Cisco Catalyst 2960 switches
that support FlexStack. Figure 4 shows a picture of two FlexStack cables connected to a fully inserted FlexStack
module. Notice how the tabs on the cables are on opposite sides of each other. The FlexStack cables are keyed as
well. Besides the tabs needing to be away from each other, the keying of the metal portion of the connector
prevents the cable from being connected incorrectly.
Figure 4. FlexStack Module with Cables
When each member in the stack has two operational FlexStack links, then the stack is operating in a fully
redundant mode. The dual FlexStack connections from each member to two other members are what provide the
redundancy. Should any single FlexStack connection break or cease to operate, then the switches in the stack will
use the remaining FlexStack connection that is provided.