Can the Same VLAN be Used/Joined on Multiple ATP Ports?

NEP

Hello,

Is there any way to allow a VLAN to hand out DHCP on multiple ports?

Our current setup has two ports configured on an ATP 800. One port has a bunch of VLANs and config for the current site. Another port just has a single VLAN. It was a bolt-on from infrastructure that we moved from another location. We are in the process of replacing that bolt-on infrastructure and were planning to reuse the VLAN.

I have configured our switches to accept traffic on the latter VLAN, however, the device I'm testing with is not getting a DHCP address. I think I've tracked it down to the device being on a different port than what the VLAN is "assigned" to.

So, the question from above is, can a device's traffic coming into the ATP on one port be allowed to join VLAN that is on another port?

If not, is there another way to accomplish this? I suppose the easiest thing to do is to create a new VLAN for the new infrastructure and allow traffic between them. However, that would prevent me from moving some pieces as is.

I'm interested to hear what other people think. Thanks.

Edit 7/29/24: PeterUK's post is marked as the answer to my question but I wanted to give a little more info. I set up a ping to a resource that would be affected by the change. Then under Config > Interface > VLAN, changed the "Base Port" on the VLAN to the new "Representative Interface" and clicked Apply. Then under Config > Interface > Port Group, changed the "Representative Interface" for the "Physical Port" and clicked Apply. The pinging device "dropped" immediately and was "down" for 15 seconds. I scheduled downtime for this, so that people would close their open files. Not all complied but their active file locks weren't lost with the disconnect. At any rate, the change went completely unnoticed.

PeterUK

If the ATP 800 has port group you can have two ports under the same Ge#

PeterUK

If the ATP 800 has port group you can have two ports under the same Ge#

NEP

It does have Port Groups. Suppose I didn't think about that with the original setup.

Right now the ports are a different interface (ge). So, guessing I would need to add the VLAN to the original interface and then change the second port (ie. bolt-on infrastructure) to the same port group. Or would the steps be different?

Is it safe to assume that this would incur downtime?

Zyxel_Melen

Hi @NEP,

Your steps are correct. But there will be a downtime during the process. The clients will not be able to find the default gateway temporarily.

NEP

Perfect! Thanks for the clarification Melen.

NEP

@PeterUK I marked your response as the answer. Also, added some information to the original post because the process was slightly different than I expected. Namely creating the VLAN on the other Base Port. You can only have one of any VLAN ID so it must be moved. Anyway, thanks for your help.