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New Member

Peculiar Trunk Config Problem

Hi ,

Recently I faced a trunk configuration problem for Cat 3548 switch series.

The scenario is like this :

3 Nos Cat 3548 connected via GBIC ports in a stack mode

2 servers connect to the switch stack.Each server has 2 Nos NIC and are connected to the switch stack. 1 NIC has an Valid eIP from a ISP and another has private IP.

Rest of the ports are workstation connected and has been divided amongst 3 vlans 4,5 and 6. 4 and 5 shall access servers in VLAN 6

VTP was configured by taking the 1st switch as the server and configuring the VTP domain ,password and enabling the pruning. VLANS were created and as there was no router or any L3 SWITCH the port connecting the servers were statically member for all the VLANs 1 4 5 6. ALl server ports in the switches were made mode multi and member of all vlans. When the GBIC port was getting configfured for trunking the switch rejected the trunk command saying that one or more ports are all ready in multi mode . So I proceeded to make the other switches in Client mode and after nearly 600 secs I made them into servers configured the VLANs and then changed them into clients. As the trunks did not get configured I had to make the GBIC ports as multi mode .Pls help me as to how I can config the trunks


Re: Peculiar Trunk Config Problem


Multi-VLAN ports and trunk ports on the same switch isn't allowed.

"A multi-VLAN port cannot coexist with a trunk port on the same switch"


New Member

Re: Peculiar Trunk Config Problem


Thanx .One more thing is that as the switch 2 switch links are in multi mode and not trunk configured are those links emulating the trunking and carrying VLAN info ? or there can be a future problem.. Pls help