Rube Goldberg would be proud ...

Rube Goldberg was a cartoonist who has a character that invented fantastic chain reaction machines. I may have been channelling his muse for inspiration in getting around my latest NBN failure:
  1. We moved house (Note: there is no such thing as an NBN relocation … its a fiction … its a cancellation and a new connection)
  2. When people order a static IP they really want the same one when they relocate it (see 1)
  3. The Sparkies came, the modem was turned off for a couple of hours … things didn't come back
On the Friday afternoon before a long weekend …

And so it begins …

Building a backup link from stuff I mostly had on hand



My 'router' is a Ubiquiti UniFi Dream Machine (UDM) Pro that supports a failover network.

Step
1 buy an SPF+ Gigabit Ethernet (Ubiquiti UF-RJ45-1G)

Step
2 Configure failover mode on UDM Pro (Create a NEW network that uses the SPF+ interface)

Step
3 Even though the SPF+ module supports 100MBps, the UDM Pro will not operate that device at that speed. Plug a 10 / 100 / 1000 switch in to convert 1G to 100M.

Step
4 Use a TP-Link MR3020 in WISP mode to connect to the Ethernet and join a WiFi Network

Step
5 Use a Telstra Pre-Paid 4GX Modem to provide Internet

BackupLink

Step 6 Curse Carrier Grade NAT (CGNAT) - basically this is the type of NAT you don't want as basically it means that there is no way to connect from the Internet to you

Step
7 Create a VPN to a service which does port forwarding

BackupLink2

At this point you can provide services from devices inside your network eg. receive mail on your mail server


Conclusion



Doable but far from ideal … the technician is coming tomorrow