Have you ever had the situation when you are abroad and suddenly the internet connection fails at home? Now you are left in the dark about your home devices since there is no way to get into your home network and check what could potentially have gone wrong.
This article explains how to get around this situation with the simplest technical approach.
The below scenario allows to automatically failover to the WWAN router (Router B) internet connection as soon as the WAN interface on the OpenWrt router (Router A) goes offline. At that moment the automatically created default route 0.0.0.0/0 with metric 0 is removed from the routing table on the OpenWrt WAN router (Router A) and the secondary default route with metric 100 becomes active which forwards all traffic from the LAN to the WWAN router (Router B).
+---------------------------------+
| |
+--WAN (xDSL/Cable)---+ Internet +----WWAN (3G/LTE)-----+
| | | |
| +---------------------------------+ |
| |
| |
| |
| |
+---------+----------+ +----------+-----------+
| Router A (Primary) | | Router B (Secondary) |
+----+---------------+ +-----------------+----+
| 192.168.001.001 /24 192.168.001.250 /24 |
| GW: 192.168.001.001 |
| Routing Table: |
| 0.0.0.0/0 -> WAN-If Metric 0 |
| 0.0.0.0/0 -> 192.168.001.250 Metric 100 |
| |
| |
| |
+-LAN-+---------+-----------------------------------+------------------------------------+-------+-----+
| | |
| | |
| | |
| | |
| | |
| | |
| | |
+-----+----+ +-----+----+ +-----+----+
| Device 1 | | Device 2 | | Device 3 |
+----------+ +----------+ +----------+
192.168.001.100 /24 192.168.001.101 /24 192.168.001.102 /24
GW: 192.168.001.001 GW: 192.168.001.001 GW: 192.168.001.001
It's assumed that the WAN router (Router A) and the local LAN is already installed and configured.
Potential Blacklist entries: