tailscale subnet routes and exit mode in LXC

After LXC container such as debian installed

1, edit the LXC container configuration file in host PVE console

/etc/pve/lxc/101.conf #LXC number 101, edit to the actual number

2, add following two lines in the container conf. file

lxc.cgroup2.devices.allow: c 10:200 rwm
lxc.mount.entry: /dev/net/tun dev/net/tun none bind,create=file

3, enable LXC container port forward in LXC console

nano /etc/sysctl.conf 

4, install tailscale script in LXC container console

curl -fsSL https://tailscale.com/install.sh | sh

5, start tailscale service with subnet and exit mode in LXC container console

tailscale up --advertise-routes=192.168.2.0/24 --advertise-exit-node #edit 192.168.2.0 base on your local subnet setup 

6, connect the tailscale admin console by the authendication output from LXC container console

7, enable subnet and exit mode in admin console

8, improve the network performance by UDP setup

apt install ethtool && networkd-dispatcher

NETDEV=$(ip -o route get 8.8.8.8 | cut -f 5 -d " ")
ethtool -K $NETDEV rx-udp-gro-forwarding on rx-gro-list off

printf '#!/bin/sh\n\nethtool -K %s rx-udp-gro-forwarding on rx-gro-list off \n' "$(ip -o route get 8.8.8.8 | cut -f 5 -d " ")" | tee /etc/networkd-dispatcher/routable.d/50-tailscale
chmod 755 /etc/networkd-dispatcher/routable.d/50-tailscale

details steps
https://tailscale.com/kb/1320/performance-best-practices#linux-optimizations-for-subnet-routers-and-exit-nodes

Done!

参考：
https://youtu.be/QJzjJozAYJo?si=XeWGWFLqtZcUiRBz