Deploying the Dell PowerConnect 8100 with the Cisco Catalyst
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Consult the User Guides for each device for more information on bridge priority settings.
Method 2: MSTP
In addition, users can minimize downtimes by using a standard protocol on the Cisco Catalyst. Spanning
tree modes available on the Cisco Catalyst WS-C6504-E with IOS 12.2(33)SXI4a are MST, PVST, and
Rapid-PVST. Of the three, only MST is an IEEE standard protocol. MS T is also the only protocol
available on both the Cisco Catalyst and the Dell PowerConnect 8100.
This option is less desirable because it requires migrating exiting Cisco devices over to MST, which were
previously running a Cisco proprietary spanning tree protocol (PVST+ or RPVST+). Such a migration
would typically require some reconfiguration and possible topology redesign. Consult the User Guides
for your devices on how to set up MST.
Network administrators often run into problems receiving multiple Cisco proprietary protocols on
standards based switches, which causes unexpected results on the network. Therefore, Dell
PowerConnect has developed an easy way to block Cisco protocols as necessary. By creating built-in
ACLs (Access Control Lists) that block individual Cisco protocols on each port, the user can now filter
out unwanted packets from their network. For example, use the following command to enable
automatic filtering of CDP packets on the interface:
console(config)#interface gi1/0/3
console(config-if)#service-acl input blockcdp
console(config-if)#exit
The no service-acl input command removes this filtering for the interface.
In the same way, administrators can block the other proprietary protocol packets individually (cdp,
vtp, dtp, pagp, udld, sstp) as shown below replacing the ( ) with the keyword:
console(config)#interface gi1/0/3
console(config-if)#service-acl input ( )
-options put in place of parenthesis
blockcdp blocks all cdp packets on this interface
blockvtp blocks all vtp packets on this interface
blockdtp blocks all dtp packets on this interface
blockpagp blocks all pagp packets on this interface
blockudld blocks all udld packets on this interface
blocksstp blocks all sstp packets on this interface
blockall blocks all cisco proprietary protocols on this interface
Use one or more of these filters on each port by running a mix of options on a single line, (for example,
service-acl input blockpagp blockudld), or simply use the blockall option to block all Cisco protocols on
the port.
Note: These interface ACLs take precedence over any global configuration that may be active on the
switch (for example, if a form of CDP is globally running on the switch, the service-acl blockcdp