Product: https://eu.store.ui.com/eu/en/products/ucg-ultra
Quad-core ARM® Cortex®-A53 at 1.5 GHz
3 GB RAM
Tailscale can be installed as per instructions for linux (both stable and unstable builds).
# /etc/default/tailscaled
PORT="41641"
FLAGS="--state=/data/tailscale/tailscaled.state"
# https://www.reddit.com/r/Tailscale/comments/1fjysnc/comment/lny2zh0/
TS_TUN_DISABLE_TCP_GRO=true
systemcdl edit tailscaled.service
# https://tailscale.com/kb/1023/troubleshooting#tcp-connection-issues-between-two-devices
# https://tailscale.com/kb/1214/site-to-site#clamp-the-mss-to-the-mtu
ExecStartPost=/bin/bash -c 'iptables -t mangle -I UBIOS_FORWARD_TCPMSS 1 -o tailscale0 -p tcp -m tcp \
--tcp-flags SYN,RST SYN -j TCPMSS --clamp-mss-to-pmtu'
ExecStopPost=/bin/bash -c 'iptables -t mangle -D UBIOS_FORWARD_TCPMSS -o tailscale0 -p tcp -m tcp \
--tcp-flags SYN,RST SYN -j TCPMSS --clamp-mss-to-pmtu'
ExecStartPost=/bin/bash -c 'iptables -w -t nat -I UBIOS_POSTROUTING_USER_HOOK 1 -o tailscale0 -m comment --comment "ts-nat" -j MASQUERADE '
ExecStopPost=/bin/bash -c 'iptables -w -t nat -D UBIOS_POSTROUTING_USER_HOOK -o tailscale0 -m comment --comment "ts-nat" -j MASQUERADE '
Outcome: it works fast for low sustained bandwidth scenarios, doesn't work for media streamimg. The UCG device has a Linux kernel version too old to benefit from TCP GRO, and there's just not enough CPU power.