Hey everybody. First time poster facing a very infuriating issue (at least for me, because I've been working on this for the last 4 days and have gotten no where). I am trying to set up a lab enviroment where I have three networks (172.x.x.x, 192.x.x.x, 10.x.x.x) which connect to three unmanaged switches; one switch per network. I am also trying to configure DHCP on this router to where if I plug in a device to FastEthernet 0 or FastEthernet 3, it gets a 172.x.x.x address from DHCP. FastEthernet 1 gets a 192.x.x.x address, and FastEthernet 2 gets a 10.x.x.x address. Here's the tricky part. When I tell the router "switchport access vlan x" and then "ip add 172.x.x.x 255.255.254.0", I get the correct network address for that port. The problem is I want all of the networks to be able to talk to each other. The only way that I know to do that is through a trunk. Once I set the ports up on a trunk, they lose the ability to get a DHCP address. Any help would be greatly appreciated.
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