Daily Usage Issues

IPv6 support?

Started by MatthewSteeples on 3,113 views

We're looking at disabling IPv4 on our VPN tunnels, but NCrunch doesn't appear to want to connect over IPv6. Looking at Resource Monitor the Grid Nodes appear to be listening on v6 addresses, but the client in Visual Studio won't accept IPv6 addresses in the config, or resolve them if the DNS entries only have DNS records. Are there plans to fix this?
Hi, thanks for sharing this issue.

The network code in place was originally built on components that do support IPv6, although it's been a long time since we tested it. It wouldn't surprise me if there is a hole in our compatibility somewhere. I'm marked this for investigation.

Do you have the option to work around this issue using a hostname or DNS alias?
For now we're OK to continue with IPv4, but I wanted to bring it to your attention. The main reason we noticed it is that we run a split-tunnel VPN, with DNS queries carried out by the user's ISP. In this instance our user's ISP (in what I assume is an effort to increase security) doesn't resolve addresses to private IP addresses, so we either need to update their host file, hardocde IPv4 addresses or use IPv6. We've gone with the 1st option for now.
Thanks, we'll check it out.
This issue has changed slightly with the release of v5. DNS entries resolve, but VS fails to connect to the Gridnode's IPv6 address with the following error:

Connection Failure: None of the discovered or specified addresses match the socket address family.
Parameter name: context
Thanks for reporting this. We've had IPv6 for a while, and none of this code has changed for several years. Is there any chance of the connection being blocked on your network? The blocking actions of firewalls and routers can sometimes kick in unexpectedly.
Not as far as I can tell. I can connect to the same device over IPv4, and I can RDP into it over IPv6. Looking at TCPView (from Sysinternals) it doesn't look like a v6 connection is even being attempted, which ties in with the error being shown. I've restarted Windows and checked there's no rules in the firewall for it (only use the built in Windows one).

Separately, although possibly related, it's not possible to specify an IPv6 address in the server box, only DNS entries that resolve to v6 addresses
MatthewSteeples wrote:
Separately, although possibly related, it's not possible to specify an IPv6 address in the server box, only DNS entries that resolve to v6 addresses


Thanks, we'll check it out.

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