PPTP Client on OpenWRT

Refresh the OpenWRT’s repository
```
opkg update
```

PPTP client installation

opkg install ppp-mod-pptp kmod-pptp kmod-nf-nathelper-extra
reboot

OpenWRT network configuration

config interface 'PPTP_VPN'
        option proto        'pptp'
        option server       'pptp.server'
        option username     'myusername'
        option password     'mypassword'
        option defaultroute '0'  # not using as default route
        option peerdns      '0'  # not using the dns servers

(Optional) Adding static routes for connection via your VPN

config route
        option interface 'PPTP_VPN'
        option target    '10.10.10.0/24'  # LAN / WAN to connect via PPTP
        option gateway   '172.16.0.1'     # gateway from PPTP