DHCP Relay function

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  • Updated 3 years ago
  • (Edited)

I want to configure DHCP in a single VLAN that has 7 APs (all AP120/121 devices)

Reading Crowdie's posts in https://community.aerohive.com/aerohive/topics/proper_dhcp_setup?topic-reply-list[settings][page]=1#...

the recommendation is to create 2 scopes on two of the APs for fault tolerance, which makes sense

But he also recommends enabling all the other APs as a DHCP relay - is that really necessary if the DHCP servers and the client devices are all in the same VLAN?

In other words, if an AP that is not configured as a DHCP server or a DHCP relay authenticates a client device, and connects the client to the same VLAN as the DHCP server APs, wouldn't the DHCP requests still be serviced by them?

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Steve Bennett

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Posted 3 years ago

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Steve Bennett

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I should clarify that in our case the management network is different from the client network. Mgt0 for all APs is configured with an IP in the 192.168.96.x range, and when the client devices are authenticated, they will be placed in a guest VLAN in the 10.x.x.x range. I am configuring the DHCP server APs to service the client VLAN using the mgt0.1 interface
(Edited)
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Roberto Casula, Champ

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No, it's not necessary to configure the other APs as DHCP relays. That would just result in a lot of unnecessary traffic. If you are implementing firewall policies, be careful to allow both broadcast and unicast DHCP requests and corresponding replies from the DHCP servers.
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Steve Bennett

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Excellent, thanks Roberto