Unable to start the vpn-client with the test enviroment

[Senyoret1]

Describe the bug
The vpn-client app does not start in, at least, visorB from the skywire-services test enviroment. This could be a problem with my testing config, but I can not be sure about that.

Environment information:

• OS: Linux

Steps to Reproduce
Steps to reproduce the behavior:

• Use the steps from VPN UI not opening issue #932 to add the vpn-client app to the visors of the skywire-services test enviroment.
• Start the test enviroment with integration-run-generic
• Open the VPN UI for visorB with https://localhost:4200/#/vpn/0348c941c5015a05c455ff238af2e57fb8f914c399aab604e9abb5b32b91a4c1fe/status
• Open the network tab of the browser dev tools, select a valid server and press the connect button, to start the VPN.
• The VPN will never be shown as connected. In the browser dev tools, you will see calls periodically made to /api/visors/{pk}/summary. In those calls, the API returns 2 as the status of the vpn-client app, meaning that there was an error, but the detailed_status property is empty, so there is no way to known what the error was.

Actual behavior
The console shows this:

Got default network gateway IP: 192.168.0.1
RTNETLINK answers: Operation not permitted
Adding direct route to 192.168.0.109, via 192.168.0.1Failed to serve VPN: error setting up direct routes: error adding direct route to 192.168.0.109: error running command "ip r add 192.168.0.109/32 via 192.168.0.1": exit status 2: RTNETLINK answers: Operation not permitted

If I start an additional visor and use it as vpn client, it works well.

[ersonp]

If you want to test a vpn connection within local visors then you need to do a two things

• Run visorB as sudo from tmux and start vpn-server either by having the auto_start:true in the config or do it from the UI.
• Run sudo setcap 'cap_net_admin+p' ./bin/apps/vpn-client in skywire-services

detailed_status being empty when there is an error is fixed here