Window server is loosing connectivity when first client login

cerri

Hello everybody,

we've this scenario:
* Windows Server 2016 with RAS enabled as NAT
* One network adapter for WAN access
* One virtual adapter for VPN functionalities

Windows is working fine, and I mean that services on Windows machine are reachable (es: RDP) on WAN access (filtered)
When a client connection is established, the Windows server is not reachable anymore but the client can navigate flawlessy (we want to use the Windows server as vpn gateway for internet purposes).

We need to stop RAS service in console to let services be reachable again.

What is wrong with our scenario?
To be honest, this configuration was working until few days ago.
Windows server is updated.

ServerConf:
port 1195
proto udp
dev tun
ca Server\\ca.crt
cert Server\\monitoring.init-s.it.crt
key Server\\monitoring.init-s.it.key
dh Server\\dh2048.pem
topology subnet
server 10.10.10.0 255.255.255.128
push "redirect-gateway def1 bypass-dhcp"
push "dhcp-option DNS 213.133.98.98"
push "dhcp-option DNS 213.133.99.99"
push "dhcp-option DNS 213.133.100.100"
duplicate-cn
keepalive 10 120
tls-auth Server\\ta.key 0 # This file is secret
data-ciphers AES-256-GCM:AES-128-GCM
compress lz4-v2
push "compress lz4-v2"
persist-key
persist-tun
status openvpn-status.log
log-append openvpn.log
verb 3
explicit-exit-notify 1[/quote]

cerri

Hello, the problem was a Windows Server Update: KB5014742

After installing this update, Windows devices might be unable to use the Wi-Fi hotspot feature. When attempting to use the hotspot feature, the host device might lose the connection to the Internet after a client device connects.

The problem was solved uninstalling that update.