firewall configuration for mosh connectivity

IPTables:

```
sudo iptables -I INPUT 1 -p udp --dport 60000:61000 -j ACCEPT
```

UFW: 
```
sudo ufw allow 60000:61000/udp
```



sources:
* https://www.digitalocean.com/community/tutorials/how-to-install-and-use-mosh-on-a-vps

