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Community Member

Trunk problem between 4506 and 2924


The problem is that I can’t configure trunk on 2924(because there isn’t any command with trunk) and if I configure the interface of 2924 with switchport mode multi-vlan and 4506 with switchport mode trunk , the protocol is down,

What is the solution of this problem please?


Community Member

Re: Trunk problem between 4506 and 2924

Sounds like the IOS image on the Cat 2924 is an earlier standard edition software. I would suggest that you look at upgrading the IOS image.

Have a look at

I have encountered this problem before, either way, without VTP capabilities, (no interface commands relating to switchport mode trunk, et al), then there is no way you will get trunking going.

Cisco Employee

Re: Trunk problem between 4506 and 2924

Do you have 8MB or 4MB DRAM on the switch? The following page should help to check to see if your switch supports trunking

Community Member

Re: Trunk problem between 4506 and 2924

I received a message from the vendor and he explain that this switch is an original Edition switch and it does not support trunking like Entreprise Edition Switch.

We find in attachment sh version

May I replace my 2924 with 2950 to activate trunking with core ?


#sh version

Cisco Internetwork Operating System Software

IOS (tm) C2900XL Software (C2900XL-HS-M), Version 11.2(8)SA5, RELEASE SOFTWARE (


Copyright (c) 1986-1999 by cisco Systems, Inc.

Compiled Tue 23-Mar-99 11:44 by rheaton

Image text-base: 0x00003000, data-base: 0x001FAEF8

ROM: Bootstrap program is C2900XL boot loader

c2924-3-6 uptime is 2 days, 21 hours, 16 minutes

System restarted by power-on

System image file is "flash:c2900XL-hs-mz-112.8-SA5.bin", booted via vty0 (172.1


cisco WS-C2924C-XL (PowerPC403GA) processor (revision 0x11) with 4096K/640K byte

s of memory.

Processor board ID 0x09, with hardware revision 0x00

Last reset from power-on

Processor is running Enterprise Edition Software

24 Ethernet/IEEE 802.3 interface(s)

32K bytes of flash-simulated non-volatile configuration memory.

Base ethernet MAC Address: 00:90:B1:9B:C3:40

Configuration register is 0xF


Re: Trunk problem between 4506 and 2924

Replace the 2924 and go to the 2950 which will do trunking , original 4 meg 2924's did not do trunking or etherchannel i believe .

Community Member

Re: Trunk problem between 4506 and 2924

You must have trunk on isl on both sides,

2924 side

int g x/x

switchport trunk encap isl

switchport mode trunk

on the other side the same.

Don´t put on auto the trunk negotiation.

Hope this help


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