iproute2¶

### add
ip route add table main default via 192.168.2.1 dev enp3s0

### delete
ip route delete table main default via 192.168.2.1 dev enp3s0

### delete, short
ip route delete table main default

### delete, shorter if main is the default table
ip route delete default

### delete, then add at the same time
ip route replace default via ...