Cisco Systems DOC-7814982 Limitations, Connecting the Stack Ports

13-8
Catalyst 2950 Desktop Switch Software Configuration Guide
78-14982-01
Chapter 13 Configuring Optional Spanning-Tree Features
Unders tanding Optional Spanning -Tree Features
Limitations
These lim itations ap ply to CSUF:
•CSUF uses the GigaStack GBIC and runs on all Catalyst 3550 switches, all Catalyst 3500 XL
switches, Ca talyst 2 950 swi tches wit h GBI C m odu le slo ts, and onl y on mod ula r Cat alyst 290 0 XL
switches that have the 1000BASE-X module installed.
•Up to nine stac k switche s can be connec ted thro ugh their st ack ports to the multid rop backbo ne.
Only one sta ck p ort pe r s witc h is supp orte d.
•Each s tac k swi tc h ca n b e c onn ect ed t o the spa nnin g-tr ee b ac kb one t hrou gh one up link.
•If the stack con sists of a mixture of Catalyst 355 0, Catalyst 3500 XL, Ca talyst 2950, an d Catal yst
2900 XL switches, up to 64 VLANs with spanning tree enabled are supported. If the stack consist s
of only Cat aly st 3550 switche s, up to 128 VLA Ns wit h spa nn ing t ree e nabl ed ar e suppor ted.
Connecting the Stack Ports
A fast transition occurs across the stack of switches if the multidrop backbone connections are a
continuo us link f rom o ne Gi gaSta ck G BI C to a nother as shown in t he t op hal f of Figure 13-6. The
bottom half of Figure 13-6 shows how to connect the GigaStack GBIC to achieve a normal convergence
time.
You should follow these guidelines:
•A switch supports only one stack port.
•Do not connect alternate stack-root ports to stack ports.
•Connect all stack ports on the switch stack to the multidrop backbone.
•You ca n connec t the open port s on the top and bot tom GigaSta ck GBICs wi thin the same stack to
form a redu ndant lin k.