Pin Ubuntu version and update docs to require privileged mode

Dockerfile

@@ -1,7 +1,6 @@
-FROM ubuntu:latest
+FROM ubuntu:20.04
 
-RUN apt-get update && apt-get install -y software-properties-common openresolv iptables iproute2
-RUN add-apt-repository ppa:wireguard/wireguard && apt-get update && apt-get install -y wireguard-tools
+RUN apt-get update && apt-get install -y openresolv iptables iproute2 wireguard
 
 COPY entrypoint.sh /entrypoint.sh
 

README.md

@@ -9,7 +9,7 @@ Now simply mount the configuration file and run! For example, if your configurat
 
 ```bash
 docker run --name wireguard                                          \
-    --cap-add=NET_ADMIN                                              \
+    --privileged                                                     \
     -v /path/to/conf/mullvadus2.conf:/etc/wireguard/mullvadus2.conf  \
     jordanpotter/wireguard
 ```
@@ -21,23 +21,3 @@ docker run -it --rm                                                  \
     --net=container:wireguard                                        \
     appropriate/curl http://httpbin.org/ip
 ```
-
-## Troubleshooting
-
-### Asymmetric Routing
-
-If you see any errors similar to:
-
-```bash
-sysctl: setting key "net.ipv4.conf.all.rp_filter": Read-only file system
-sysctl: setting key "net.ipv4.conf.default.rp_filter": Read-only file system
-```
-
-Then your host is set to discard packets when the route for outbound traffic differs from the route for incoming traffic. To correct this, you'll want to set these values in `/etc/sysctl.conf`:
-
-```bash
-net.ipv4.conf.default.rp_filter = 2
-net.ipv4.conf.all.rp_filter = 2
-```
-
-Afterwards, reboot.