OpenVPN - Multiple Phones Loose VPN, never reconnect

[cmariotti]

We have a few clients with their Yealink phones behind their own firewalls... these phones each make an OpenVPN connection to our pfSense Firewalls at our datacenter which hosts their phone servers.

Every so often, their phone(s) loose their OpenVPN connections... Sometimes it is just one phone... sometimes it is both phones... they no longer have OpenVPN connections and are never seen again until the phone is powered off/on. Once powered on, no problems connecting / working.

What can I do so that the Yealink phones reestablish a connection, no matter how long their internet might go down for (no clue if this is the actual problem, is there a way to pull up the logs specifically for lost connections)? Any suggestions on how to keep things running smoothly?

Here is the .cfg file:

dev tun
persist-tun
persist-key
cipher AES-128-CBC
auth SHA1
tls-client
client
resolv-retry infinite
remote 172.172.172.172 1197 udp
ca /config/openvpn/keys/ca.crt
cert /config/openvpn/keys/client1.crt
key /config/openvpn/keys/client1.key
tls-auth /config/openvpn/keys/ta.key 1
ns-cert-type server