Maximun VLANs in my MX84

[Johnfnadez]

I have 21 Vlans in my MX and each one is for an SSID just 6 not. I´m having issues with the DHCP Leases in the last vlan that I configured.

Does anyone know if Meraki has a limitation for that or a best practices for the VLANs specifically.

Regards

[TheITWay]

Hello @Johnfnadez, 

The Security Appliances do not limitation regarding the number of VLANs allowed. That will depend on the memory and the CPU utilization and other features you are running as well (content filtering, threat protections, VPN tunnels, etc). 

What kind of issues are you having in those VLANs:

- Is the MX not providing IP addresses?
  + Did you take pcaps to see if there are DHCP Discovers and Offers?

- Does the MX say that there are not available IP addresses?

  + Did you check the DHCP section in the Appliance Status and the IP reservations in the DHCP section?

- The MX does not provide IP leases at all?

  + Did you check the DHCP configuration for that VLAN?

You can find more information about the MX84 and the comparison against other MXs here:
https://www.lonsys.co.uk/wp-content/uploads/2016/11/meraki_whitepaper_mx_sizing_guide.pdf

[MerakiDave · Accepted solution]

No there is no limitation but you may come to a point (with hundreds or thousands of VLANs) that it becomes rather cumbersome to maintain and administer that on a single page in Meraki Dashboard.  Not only that, but if you're scaling it up to hundreds of VLANs or more, you're going to want to offload DHCP services to a powerful external DHCP server.

At the scale you mentioned, I'm not concerned about the MX.  What I *am* concerned about is that you're indicating that 15 of your VLANs are for SSIDs and that is likely an issue if this is within the same coverage area.  Even though you can configure and run 15 SSIDs in a wireless network, that is never a good idea, try to limit that to 3 or 4 or maybe 5 if you can.  Control and Management frames are robustly modulated and every additional SSID configured will steal away that much more airtime utilization and drive up the duty cycle dramatically, impacting (slowing down) all clients.

[BrechtSchamp]

As a small addition to what @MerakiDave wrote above.

You may want to look into the option of serving multiple VLANs over one SSID. More info about that here:

https://documentation.meraki.com/MR/Client_Addressing_and_Bridging/VLAN_Tagging#Per-User_VLAN_Taggin...