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4507 Supervisor IV Etherchannel on GBICs

Please help...

We have 2x 4507 chassis with 2x supervisor IV blades in each.

We would like to use both GBIC interfaces on each supervisor to set up etherchannel between them.

4507-Switch-1 4507-Switch-2

1/1 ----------------------> 1/1

2/1 ----------------------> 2/1

Commands used...

interface type mod/num

channel-group 1 desirable

Have used the same commands on all GBIC ports and tried the channel protocol as both PAGP and LACP.

Please can you assist.

Kindest Regards...

Kai Nicholls

Cisco Employee

Re: 4507 Supervisor IV Etherchannel on GBICs

The Supervisor Engine IV chipset supports up to 32 non-blocking Gigabit Ethernet interfaces providing aggregate throughput of 48 Mpps. A fully loaded Catalyst 4507R switch in a redundant configuration with five 6-port Gigabit Ethernet non-blocking line cards (30 interfaces) and 4 uplinks on the Supervisor Engine IV requires 34 non-blocking Gigabit Ethernet ports. Thus, only in a redundant Supervisor configuration, regardless of the number of line cards, only interfaces Gigabit 1/1 and Gigabit 2/1 are active for Catalyst 4507R. The interfaces Gigabit 1/ 2 and Gigabit 2/2 appear in the configuration, but the line protocol is never active on them. These interfaces (Gigabit 1/2 and 2/2) may be configured as needed to save any configuration. The non-redundant switch configuration yields two active Supervisor Engine IV uplinks.

Re: 4507 Supervisor IV Etherchannel on GBICs

The configuration you have done should work, BUT are the ports physically configured the same? The EtherChannel will not form if the ports are not configured identical - i.e. If the are configured as VLAN trunks they MUST have the same Native VLAN, the same list of allowed VLANs, the same encapsulation type, the same QoS trusted state. Also when you should have a Port-Channel interface in the configuration - this also needs the same config as the physical ports.

I would flatten the physical port configurations and shut them down. Then apply the 'channel-group 1 mode desirable non-silent' command and do a 'no shut', this should allow the etherchannel to form. When it has formed apply configuration changes to the 'Port-Channel' interface, these should be pushed down to the physical interfaces.