External DHCP Server setup

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I have a ZD5000, and trying to configure a AP to get ip from a NEW external DHCP server (Win2003 or Win2008). AP is currently working fine and receiving DHCP for another OLD external DHCP server (L3 switch). AP port is tagged with VLANs 7&8, VLAN ID is 8. NEW DHCP server sits on VLAN 9 but I have configured a scope on the server to hand out address in the format: xx.xx.8.0/23; OLD DHCP server sits on VLAN 7 and hands out xx.xx.7.0/24. ZD is set with a static ip: xx.xx.7.x/24 (VLAN 7). Both DHCP servers will remain as I have other APs on the old and serves different purposes. I just need this one AP to hand out address the would put those devices on VLAN 8 thus the scope setup on the new server. How do I configure?
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E Q

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Posted 3 years ago

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Monnat Systems, AlphaDog

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Hi EQ,

I understand that you want everything else to be same like SSID or user however you just want one specific AP to get IP from VLAN 8. Correct?

If yes, This is Doable.
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E Q

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Correct , I want devices that connect to that AP to be on VLAN 8. Everything else stays the same.
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Eizens Putnins

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To make DHCP server work with this VLAN, you must add it to L3 switch DHCP relay configuration  (otherwise it will not get requests from different VLANs) and add the  scope to the DHCP server. You also probably want to configure Option 43.
You can use 2 DHCP servers, but usually you don't want to have 2 different DHCP servers on network with different configuration, it is potentially source for problems.
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Ramprakash

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Hi EQ,

one option is what Eizens suggested. Second one is as below:

Firstly, you need to create new set of WLAN's which 1) you want to be on that AP. 2) Need to get IP from VLAN 8. During the process just have a distinct WLAN Name however keep ESSID same as the one which you want on the AP to be broadcasted..Secondly, in the advanced setting of THAT wlan you tag it with VLAN ID 8.

By doing so you will have two WLAN's on ZD with same SSID however different network configuration like in your case VLAN info.

Now you need to create a new WLAN group and add newly created WLAN's just now to them.

Then apply these new crealed WLAN group to the AP on both radios in AP configuration.

This should do it.

regards

Ramprakash
(Edited)
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Michael Brado, Official Rep

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Adding to Ramprakash's comment.  Trunk VLAN 8 to your APs, and clients who connect to a WLAN tagged for VLAN 8, will have their DHCP requests tagged before they hit the Ethernet at the AP.
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Eizens Putnins

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1. Adding to proposed solution -- you still need to add new DHCP server to DHCP relay config, as it is providing IP to VLAN8, but sits on VLAN9, otherwise clients will not get IP addresses.

2. Much better way to replace VLAN for SSID on any AP is to create new AP group,  set for group VLAN substitution to 8 for respective WLAN and move needed AP to this group.

Hope it helps,

Eizens