MG21 and Failover

[RobertStark]

I am posting here as I don't see any other topic area which covers cellular and I figured this is a setting for my network on my SD-WAN MX-84. Hi, I just received the MG21, got the license registered and the cellular SIM put it. All seems to be working. The only thing I am having a hard time with is finding out how to do the cellular failover. Maybe I am not seeing the proper documentation. But my needs are this. I would like the traffic to be directed through cellular only after a network failure of my main uplink (from fiberoptic link). I was told there was some sort of rules that could be set on the firewall. Any pointers to the info would be great. Thanks.

[KarstenI · Accepted solution]

You find the relevant settings under "SD-WAN & traffic shaping". Assuming the MG21 is connected to WAN2, you have to:

• Set the primary Uplink to WAN1
• Disable Load balancing
• Disable Active-Active AutoVPN
• Have no Flow- and uplink preferences configured.

Now your fibre line is primary and the cellular gateway will be used as a backup.

[RobertStark]

Thank you for that answer. I started to work on this today and realized I might have a problem. I am wondering about my configuration. I would like to plug in my MG21 directly to my MX84 Security Appliance as a WAN2. However, for some reason the "bigger and better" security appliance I bought does not have POE. which means I would have to purchase a power source and makes this less appealing as this is for emergencies like when the internet goes out (and power goes out). I have backup electricity for all of my appliances. Anyways, I can plug it in to my MS220-48LP switch which can provide POE which plugs into my security appliance. Does this complicate the situation if I am trying to stick with POE to power my cellular gateway? Any thoughts? I also though of the possibility of using two wires. There are two ports on my Cellular Gateway. I could plug one ethernet cable into the WAN2 on the security appliance and the the POE port on the cellular gateway could be plugged into the switch for power.

[KarstenI]

As a rule of thumb, the external traffic should not run through an internal switch.

I would go for an external power injector. Either a regular one or something like a ZyXel 5-port PoE switch as I have to connect my MG41 to the MX68.

[RobertStark]

Thank you!

[RobertStark]

Thanks again. I would like to say for the record, that Meraki should have POE on at least a couple of the ports on the Mx84 for this very reason. I realize that the cellular ran on USB at one time, but if they offer a product that uses ethernet and POE, like the MG21, then they should have a solution on the security appliance to match. 

[KarstenI]

Well, the newer models, like the MX85, has PoE on one of the WAN-ports. But the older devices all don't have this.