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C3750

I'm setting up a C3750 48 port switch in an IDF that connects to our 4006 switch in our MDF. Question is connecting the two switches together VIA fiber does the uplink on both ends have to be a trunk port? "switch port mode trunk" or "switch port mode access"? Also both these switches and ports are on the same vlan.

I?m confused as to which commands to use at what times,

Switch port mode trunk and switch port mode access. I understand that access is for connecting hosts and trunks are used for carrying multiple vlan traffic but I have seen both commands used at different times.

Any help would be appreciated.

Adam

1 ACCEPTED SOLUTION

Accepted Solutions

Re: C3750

Adam,

Your understanding of access/trunk modes is partially correct. Access mode doesn't have to be necessarily connecting hosts. Ports connecting switches can be set to access mode as well if the port doesn't have carry traffic for multiple VLANs.

If you specify the mode to be access then the port would never become a trunk port under any circumstance. It's better if you can set the mode to access/trunk without having the port dynamically form access/trunk association on that port.

The two modes can be configured as follows:

Switchport Access Mode:

int f0/1

switchport mode access

switchport access vlan 10

Switchport Trunk Mode:

int f0/1

switchport trunk encapsulation (isl/dot1q)

switchport mode trunk

HTH

Sundar

3 REPLIES
Purple

Re: C3750

Adam,

You need to use 'switchport mode trunk' if you want it to come up as a trunk link. The commands are mutually exclusive and you should not be able to configure both at the same time.

Paresh

PS. Pls do remember to rate posts

New Member

Re: C3750

thanks Paresh, what would it mean if I configured it as an access link?

Re: C3750

Adam,

Your understanding of access/trunk modes is partially correct. Access mode doesn't have to be necessarily connecting hosts. Ports connecting switches can be set to access mode as well if the port doesn't have carry traffic for multiple VLANs.

If you specify the mode to be access then the port would never become a trunk port under any circumstance. It's better if you can set the mode to access/trunk without having the port dynamically form access/trunk association on that port.

The two modes can be configured as follows:

Switchport Access Mode:

int f0/1

switchport mode access

switchport access vlan 10

Switchport Trunk Mode:

int f0/1

switchport trunk encapsulation (isl/dot1q)

switchport mode trunk

HTH

Sundar

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