vlan and dhcp

we've a few kvm's that have a mix of vlan tags. they are dhcp clients.

I'm trying to figure out where to put the dhcp server.

Now if I use a kvm for dhcp server with a vlan set to 20 , only other vlan20 kvm's get a dhcp address .

I wonder how others deal with this.
Does it make sense to just use a dhcp server on each vlan?

We have a layer-3 switch...

Also when I run dhcp on a physical box and that box has vlan 20 set, kvm's with vlan 30 do get an address.

The issue could be with some of the per port settings on the switch....

But in general I'd like advice on where it is best to put the dhcp server - kvm or pve host etc. Any suggestions?