Meraki MX100: Run as DHCP or Relay DHCP to another server

[mugrene]

Greetings

I am configuring Meraki MX100 to my network (to replace cisco asa 5525-x), this will be sitting in my network rack at HQ. Currently I have windows server 2019 running the following roles: DHCP (Different scopes are running), DNS, ADDS,....

Beside this, I planning to create different VLANs in new Meraki MX100. Should I use MX100 as DHCP server? or relay to that Windrows server running DHCP as role.What is the best choice? use Meraki MX100 as DHCP Server or relay DHCP to another server?

Thank you for your valuable support.

[PhilipDAth]

Do you prefer to do your management in Windows or the Meraki Dashboard?  Put DHCP wherever you prefer to do management.

[mugrene]

Hi @PhilipDAth 

Thank you for your quick feedback. I am looking the one which performs well and which simplify and leads to easy management. Meraki DHCP or Windows server DHCP?

[DarrenOC]

Hi @mugrene , both perform well and are easy to manage.

Just a thought - if the MX fails you’ll also loose your DHCP capabilities.  If this was a branch site I’d say go for it and use the dhcp on the Mx but it’s not it’s your HQ where I presume the majority of your users and main services reside.

[DarrenOC]

Hi @mugrene 

as this is your HQ site and you already have the server in situ I would leave the DHCP scopes on the server and relay.

[KarstenI]

One more reason to run DHCP on the server and not the MX: All systems are automatically registered in DNS and can be tracked and/or accessed by hostname/FQDN.

[mugrene]

Hi @KarstenI 

So, you advise me to run DHCP on windows server rather than on MX, unfortunately once I hit save it gives the following error for the subnet where DHCP is belonging. Any help?

[Claes_Karlsson]

I don't think it's necessary to do a relay to the windows server if the server lives in the same broadcast domain, since the DHCP discovery/offer/request is all L2 traffic and won't traverse the MX. I think that is what the MX is trying to say to you, unless the 10.10.0.254 address belong to the MX. But I would put my money on the first one 🙂

/CK

[CptnCrnch]

Correct. DHCP will send a broadcast, therefore there's no need to relay within the same broadcast domain.

[mugrene]

Hi @CptnCrnch 

For my case, VLAN 100 (HQ SERVERS)10.10.0.0/24 for Client addressing, should I use "run a DHCP Server: option 1 in below picture" or Do not respond to DHCP request: option 2 in below picture"

[CptnCrnch]

Your MX simply shouldn't respond to DHCP requests in that subnet. Your existing DHCP server will handle it automatically.

[Claes_Karlsson]

Option 2 for sure, do not respond to DHCP requests.

/CK

[KarstenI]

Option 2) "do not respond to DHCP requests" as there is already the "real" DHCP server in that VLAN.