Openvpn bus error on TP Link Archer C20 v4

Hello there, I just bought a TP Link Archer C20 v4, and I have flashed it via tftp boot using this guide:;a=commit;h=5bdd238b634a34b038fbea9046893de29a77c000

All is working well, and I am using it as an access point to extend my ISP's fiber modem+router. The reason why I'm using another router, is because my ISP's router didn't have any QoS feature, so if one person use the bandwith heavily, all other user will suffer very slow internet (a simple HD Netflix stream could cause other person unable to load facebook). C20's base software also has QoS, but unfortunately it only work for connection via WAN, which I didn't have because I extend the network through the LAN port.

The problem is, once I wanted to install openvpn using this tutorial , my openvpn doesn't even work. After doing all of these, and I type "openvpn" or "openvpn --h", it just shows "Bus error". I only installed SQM other than openvpn, is there something wrong with my hardware, or am I doing something wrong?

Please do let me know if I have to provide some kind of log/data. I am quite new in OpenWRT, so I didn't know what to provide at first. Thank you for your time.

Are you running the latest version, 18.06.1?

Yup, I should already have the latest version of the OpenWRT, following the tutorial method.

Generally you wouldn't start OpenVPN manually. It needs a config file to work. If you are using a commercial service they should provide a suggested .ovpn file. Copy that file to your router, for example make a directory /etc/config/openvpnfiles. (this location is suggested since the entire /etc/config directory is kept when you upgrade to a new OpenWrt version). Then edit the /etc/config/openvpn to point to that file using an option config line. Remove all other configurations from /etc/config/openvpn, if you need to fine-tune the configuration edit the .ovpn file instead.

Thank you for your explanation. I should’ve elaborate what I had done first. I have followed the tutorial, installed luci-app-openvpn etc, and copied my provider’s .ovpn. I have edited the /etc/config/openvpn file too. Unfortunately, when I started them via luci, nothing happened. So I started checking around via manual command, and I found that even single “openvpn” command shows “Bus error”, not the help descriptions as usual.

That being said, I have restored my router to its stock firmware, since this openwrt’s connection keeps disconnecting after some time. I used LAN to WAN method, and now I can use my router’s Bandwith Control. For VPN, I just use my Raspberry Pi VPN AP.

Problems not solved, but I don’t have that problem anymore. Thanks for helping me :slight_smile: