Default Route Missing or Inactive

What happens when a router has no default route, and how to confirm one is present and active in RouterOS.

• troubleshooting
• routing

What a missing default route looks like

Traffic to directly connected LANs works fine (e.g. you can access the router and internal servers), but anything destined for the internet simply fails. When you try to ping 8.8.8.8 from the router’s terminal, you will instantly get a no route to host error.

1. Confirm a default route exists

Check the routing table for the destination 0.0.0.0/0. This acts as the “catch-all” for any IP address the router doesn’t explicitly know about.

CLI Check:

/ip route print
# Look for a line where dst-address is 0.0.0.0/0

If it’s missing entirely, you must add one:

• If using DHCP WAN: Ensure your /ip dhcp-client has add-default-route=yes.
• If using PPPoE WAN: Ensure your /interface pppoe-client has add-default-route=yes.
• If Static WAN: Add it manually: /ip route add dst-address=0.0.0.0/0 gateway=YOUR_ISP_GATEWAY.

2. Confirm the route is actually active

A route can exist in your configuration but be inactive.

CLI Check:

/ip route print detail

Look for the active and reachable flags. If the gateway says unreachable, the router cannot physically talk to the next-hop IP.

• Is the WAN cable unplugged?
• Did you type the gateway IP incorrectly?
• Is the gateway IP outside of your WAN interface’s subnet? (e.g., your WAN IP is 10.0.0.2/24, but your gateway is set to 10.0.1.1 - this will fail).

3. Multiple default routes (Multi-WAN)

If you have two WAN connections and both have a default route, how does the router know which one to use?

RouterOS looks at the distance (Administrative Distance). The lower the number, the higher the priority.

• Primary ISP: distance=1
• Backup ISP: distance=2

If you are using two DHCP Clients, open their properties and change the Default Route Distance. Otherwise, they might both receive a distance of 1, causing traffic to randomly load-balance or fail.