# How to bypass "Error: Nexthop has invalid gateway" when adding routes on Linux I was having issues to add a route to my Linux home lab virtualization host, and it was not working and was instead outputting that error all the time. I guess that had something with the actual complexity of my home lab architecture, especially how my VMs had access to the interned and how I was accessing them from the Internet. ```bash davidassigbi@hp-elitebook:~$ ip route default via 10.188.0.1 dev wlo1 proto dhcp metric 600 10.10.10.0/24 dev enp0s25 proto kernel scope link src 10.10.10.2 metric 100 10.188.0.0/16 dev wlo1 proto kernel scope link src 10.188.197.57 metric 600 169.254.0.0/16 dev mybridge scope link metric 1000 192.168.1.0/24 via 192.168.1.5 dev mybridge 192.168.122.0/24 dev virbr0 proto kernel scope link src 192.168.122.1 davidassigbi@hp-elitebook:~$ sudo ip route add 100.96.1.0/24 via 192.168.1.1 dev mybridge Error: Nexthop has invalid gateway. davidassigbi@hp-elitebook:~$ ip a show mybridge 4: mybridge: mtu 1500 qdisc noqueue state UP group default qlen 1000 link/ether ba:5a:99:6e:19:87 brd ff:ff:ff:ff:ff:ff inet 192.168.1.5/24 brd 192.168.1.255 scope global mybridge valid_lft forever preferred_lft forever inet6 fe80::b85a:99ff:fe6e:1987/64 scope link valid_lft forever preferred_lft forever davidassigbi@hp-elitebook:~$ sudo brctl show mybridge bridge name bridge id STP enabled interfaces mybridge 8000.ba5a996e1987 no vnet1 vnet4 vnet6 ``` And the final solution was to add the `onlink` argument, which according to the `ip route` man page says it forces the kernel to assume the interface is directly connected to the system while it actually is not. ```bash davidassigbi@hp-elitebook:~$ sudo ip route add 100.96.1.0/24 via 192.168.1.1 dev mybridge onlink ``` **Resources:** - https://man7.org/linux/man-pages/man8/ip-route.8.html : look up the onlink on the page - https://unix.stackexchange.com/a/644486 : a question on stackexchange discussing the same issue