Scenario

You need to reach a remote subnet that isn't covered by the default route, but you don't want to make any permanent configuration changes.

Task

Check the current routing table to confirm the 10.20.0.0/16 subnet is not present, add a temporary static route for the 10.20.0.0/16 subnet via gateway 192.168.1.1 using interface veth0.

Example

# Before (no route to remote subnet)

10.20.0.0/16 subnet not in routing table
Cannot reach remote network
Need temporary access without permanent changes

# After (temporary route added)

10.20.0.0/16 via 192.168.1.1 dev veth0

Route active and verified
Remote subnet accessible

Step 1: View the current routing table

ip route show

Step 2: Add the temporary static route

sudo ip route add 10.20.0.0/16 via 192.168.1.1 dev veth0

This tells the system to route all traffic destined for the 10.20.0.0/16 network through gateway 192.168.1.1 on interface veth0.

Step 3: Verify the route was added

ip route show

Look for the line: 10.20.0.0/16 via 192.168.1.1 dev veth0

Step 4: Test connectivity

ping -c 2 10.20.0.5

Replace 10.20.0.5 with an actual IP in the remote subnet if you know one exists.