Google SSO Authentication failure on IPv6-only clients due to auth.pritunl.com lacking AAAA record

Pritunl Pritunl VPN
1

Hello Pritunl Support Team,

I am reaching out to report a connectivity issue when attempting to authenticate via Google SSO from a client machine that only has an IPv6 address.

Problem Description: The authentication flow fails at the final stage because auth.pritunl.com does not seem to support IPv6.

Steps to Reproduce:

  1. Use a client machine with only an IPv6 stack enabled.

  2. Initiate the VPN connection.

  3. The client is redirected to our self hosted Pritunl server.

  4. The server successfully redirects to the Google Login page.

  5. After successful Google authentication, the browser attempts to redirect to auth.pritunl.com to finalize the handshake.

  6. The connection fails because the client cannot resolve or reach auth.pritunl.com.

Technical Details: A DNS lookup confirms that auth.pritunl.com only has an A record (IPv4), with no AAAA record available:

$ host ``auth.pritunl.com
auth.pritunl.com`` has address 129.213.65.110

Because of this, any client in an IPv6-only environment is unable to complete the SSO flow. I have verified that if Google SSO is disabled, I can connect to the VPN without issues, which confirms the bottleneck is specifically the reachability of the Pritunl auth portal.

Request: Are there any plans to add IPv6 support (AAAA records) to auth.pritunl.com? This is becoming increasingly critical as we move toward IPv6 infrastructure.

Looking forward to your feedback.

2

Hi @zach
I wanted to make sure this technical report didn’t get buried. It seems to be a reproducible connectivity issue with the auth server on IPv6. Would love to hear your thoughts on this when you’re available.

3

I was going to do this last weekend to limit the impact of any disruptions but forgot. I will try to do this later tonight.

4

Thank you for the reply and for looking into this!

I’m glad to hear that this is on your radar. I am happy to wait for an update.

5

IPv6 is now active for auth.pritunl.com there’s no plans on activating it for app.pritunl.com due to older versions of Pritunl using app.pritunl.com/ip to get the public IPv4 address of the Pritunl server for the auto configuration. But the clients don’t need to access app.pritunl.com only auth.pritunl.com. Once enough servers are updated to use app4.pritunl.com and app6.pritunl.com it will be transitioned to support both IPv4 and IPv6.

6

Thank you for the update!

I’ve just verified it on my end, and I can confirm that the AAAA record for auth.pritunl.com is now present. The Google SSO authentication flow is working perfectly for our IPv6-only clients.

Really appreciate you taking the time to fix this!

Best regards, Serhii