Nighthawk M5 as backup to existing Fibre via Orbi Mesh 750 series

[Questforspeed]

Hi - just got FTTP 1gb this week after using the Netgear M5 mobile router for the past year through an Orbi mesh 750 system.  Did the job with 4G LTE download of 100+ but obviously no comparison with the new fibre.  I would like to still utilise the M5 as a backup plan should the fibre go down (believe I would use the 'Wifi always on' feature) and push through the mesh system.  Unfortunately not much in the way of advice in terms of how to integrate this into an existing network.  Presume I would have to hard wire the M5 to the ONT and then somehow into the router or the M5 into a LAN in the router?  I'm using the existing orbi 750 router as the only router and did away with the Sky one (went into advanced settings on the router page and filled in the DCHP option 61).  

Any help / thoughts appreciated....

Thanks!

[CrimpOn]

This is exactly what the product data sheet claims (page 3)

https://www.netgear.com/images/datasheet/mobile/MR5100C.pdf 

It appears that page 33 of the User Manual describes what you want:

https://www.downloads.netgear.com/files/GDC/MR5100C/MR5100C_UM_EN.pdf 

The configuration would be ONT --> connected to---> M5 with Ethernet ---> connected to --> Orbi RBR750 with Ethernet

This will be more complicated to manage than a single ISP connection.  Not certain what the data capacity of the M5 is compared to the fiber connection.  Sort of doubt that it was designed to push gigabit traffic, for example.

[Questforspeed]

Hi - thanks! 

I think just reading simply, on the product data sheet link you sent (page 3), I should just be able to link via ethernet the M5 to a LAN port at the back of the Orbi Router (which acts as the main router from the ONT).  It could just be a case of trial and error and I switch off the fibre signal to see if the M5 kicks in or not?  The problem with putting the M5 as the primary point from the ONT is that it only has one ethernet port - so it can't effectively daisy chain to the router then -unless I get an ethernet splitter?  Doesn't really say? 

Worst case I just simply turn on the M5 when anything should go down and use as hotspot as intended but it would have been nice to have seamless coverage.

Thanks 

[CrimpOn]

(The day has just started and already I have been too hasty and spouted off total nonsense. Geez)

Yes, the M5 has only a single Ethernet port.  It appears that "automatically switch from Ethernet to the 5G/4G network" works when the M5 is the primary router and everything is connected to it over WiFi.  No way to connect the RBR750 system.

One way to achieve redundant internet is place a router ahead of the Orbi router which supports two internet connections. One such device is the Ubiquiti Edgerouter X:

https://store.ui.com/us/en/collections/uisp-wired-advanced-routing-compact-poe/products/er-x 

(not clear to me why it would be $59 at the Ubiquiti store and $72 on Amazon)

Page 72 of the User Manual explains how to set up Load Balancing.  Page 73 describes how to set up"Failover" so that one network is not used unless the other network fails.

Another solution is to install a Firewall which allows for multiple internet connections, such as the pfSense Netgate 1100.

https://shop.netgate.com/products/1100-pfsense?_gl=1*1r360d4*_ga*OTg1Njc5NjQ0LjE3MDUwMDEzMDc.*_ga_TM... or a Firewalla.

Any of these solutions involve investment in hardware plus the time required to set up and manage it all.  In addition, placing one of these devices in the network also creates at "Double NAT" situation which can interfere with specific internet applications.  If automatic failover is a requirement, this would be the direction to go.  On the other hand, if the primary ISP is relatively reliable, digging out the M5 when they fail is probably an easier route.

[Questforspeed]

Hi - thanks for clarifications.  Yes I thought as much the 'always on wifi' feature for the M5 would work if that was the primary router distributing the signal, with the fibre connected and the 4G coming on only when that failed.  The issue clearly is trying to use that as a passthrough to the Orbi 750 router and there's no other ethernet connection from the M5 to forward on the fibre and because it needs to have 'always on wifi' we then have the double NAT situation.  I think I can deal with a short period of downtime in the house if the worst happens and I simply connect the M5 to the Orbi Mesh in offloading mode.  Short of getting a mesh with a sim card feature in there's not much I can do really and I've invested heavily in the Orbi and several satellites.  

Thanks again!