I am running an OpenVPN 2.4.9 server (without Access web interface) on a CentOS 7 machine for ~30 employees using Windows 10 laptops.
Recently, I noticed some people were disconnecting with UDP error 10051 after a few minutes of being connected. This error only occurs once in a while and always at the same clients and disappears after rebooting the operating system or after waiting an undefined amount of time.
According to Microsoft's documentation this error is indicating that it cannot reach the network.
The clients can still use other networking functions (i.e. browsing the web) so general internet connectivity is available and the windows firewall is not configured to block the port I am using (otherwise the connection couldn't have been established in the first place,right?). There are no firewalls or other middleboxes other than the windows firewall between the server and it's clients.
Is there any advice that can be given to solve this riddle?
Server config:
user nobody
group nobody
persist-key
persist-tun
port 1094
proto udp
proto udp6
dev tun
ca easy-rsa/pki/ca.crt
cert c.crt
key c.key
dh dh.pem
cipher AES-256-CBC
auth SHA512
comp-lzo
reneg-sec 0
inactive 0
keepalive 10 36000
Client config:
client
dev tun
remote vpn.domain.tld 1094
comp-lzo
ca a/ca.crt
cert a/d.crt # EasyRSA generated
key a/d.key
auth-nocache
auth-user-pass
cipher AES-256-CBC
auth SHA512
remote-cert-tls server
reneg-sec 36000
0 Answers