Issue with Using AES-256-GCM - Constant Reboots

[pinkfloyd210]

Hello everyone,

I recently updated my OpenVPN to 3.4.3v and I’ve been intrigued by the introduction of the Data Channel Offload (DCO) feature which is designed to improve performance. I understand that it’s essential to use modern security standards, so I’ve changed my configuration to use AES-256-GCM for encryption.

However, I’ve encountered a persistent issue where my connection repeatedly reboots when GCM is enabled. Below is the error log for reference:

Code: Select all

tun error: ovpnagent: communication error
event: tun_setup_failed ovpnagent: communication error
event: disconnected

I’ve confirmed that this issue is specific to when I use any GCM, as switching to a CBC cipher alleviates the reconnection problem, but I’d prefer the security benefits that GCM offers and DCO

Has anyone experienced a similar issue or can provide insights into what might be causing this instability? Any guidance on how to maintain the use of AES-256-GCM without these frequent disconnects would be greatly appreciated!

my config:

Code: Select all

client
dev tun
proto tcp
remote **.com 443
cipher AES-256-GCM
auth SHA256
resolv-retry infinite
nobind
persist-key
persist-tun
mssfix 1460
verb 3
keepalive 10 30
auth-user-pass
client-cert-not-required

Thank you in advance for your time and help.

[solo]

AES-256-GCM is not supported. It might be included in the developer edition.

[pinkfloyd210]

AES-256-GCM is not supported. It might be included in the developer edition.

I tried DE and yes GCM worked fine
but DCO still not