Hello everyone -
I'm having a very strange issue with a new Catalyst 4506 I'm standing up right now, and haven't seen this before... I'm just about finished configuring the device, and am putting the final configurations in and have run into some trouble.
The switch is very basic, a SUPIV, an 18 port GBIC blade, and a 48 port gigabit ethernet blade. I'm trying to configure my GBIC ports set to trunking, with dot1q encapsulation, and the first 2 ports it works without an issue. On the rest of the ports on the blade, the command simply isn't there. Basically, i'm trying to do an - interface range gi2/1 - 2/8, switchport trunk encapsulation dot1q, and then switchport mode trunk. After inputting the switchport trunk encapsulation command, I get the message "command failed on interface gigabit ethernet 2/3", aborting.
Not sure what's causing this, if anyone has seen this issue before, please shed a little light .
Yes, the command works without any issues on the 48 port blade. That said, I could just get away with using switchport mode trunk without setting an
encapsulation, the command doesn't fail. From the research that i've done it seems like there's a limit on how many ISL trunks you can configure on a 4500 series switch, but that really doesn't make any sence to me.
The ports are all unconfigured, there's a configuration on the switch, but this is the first time i've tried to setup the different interface configurations.
It is a limitation on that particular module. The first 2 ports are non-blocking and support either ISL or 802.1q trunking. The remaining 16 ports which are oversubscribed only support 802.1q trunking and so the "switchport trunk encapsulation ..." command is not available for those ports.