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New Member

Migration of users in different vlans of 3750 Switches

I have 30 switches of access (3750). I require To migrate 1200 users connected to this switches of vlan 1 ( /22) to vlan 2 ( /22). They changed in server DHCP the rank /22 to /22. ¿In this case the only solution is to change the ports of switches of vlan 1 to vlan 2?. Can i configure 2 vlans in the ports of switches 3750?. What you recommend to make this migration in the efficient form?


Re: Migration of users in different vlans of 3750 Switches


I would suggest u to use VTP i.e if u create the new vlan on the vtp server it is going to be propagated to all switches in the VTP domain.And where r all these vlans are terminating i mean where is the SVI for this vlan create a SVi for this vlan and assign it a DHCP HELPER-ADDRESS user it.then as u change the vlan ports on the switches they are going to get the ip address form the range u specified.



Re: Migration of users in different vlans of 3750 Switches


No you cannot make a port part of 2 vlans. What really you can od is to use the range command and assign all the ports that you want from vlan 1 to vlan 2 on every switch.

conf t

interface range gig 0/1/0 - 12

switchport access vlan 2

HTH, Please rate if it does.

-amit singh

New Member

Re: Migration of users in different vlans of 3750 Switches

well you could use the command interface range fastehternet 0/1 - 48 (change the command according to your ports) and then execute the switchport access vlan 2 command.

Like this all the ports will be changed in one shot. When to do it.....well during a weekend.

The biggest problem is see is that the workstations have to get a new IP address from DHCP after the migration so i suggest that you put the lease expiration to one day. Like this all the workstations will ask for a new ip address every day and after the change to vlan 2 they will ask an ip and everybody will have connectivity and it should be transparent for the user than.

FYI A switch port can always only belong to a single vlan or it has to be a trunk port to support multiple vlans what is not recommended in your situation.


rate this post if it helped


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