How can I ping IPv6 from a Google cloud instance

Question

I have a Google cloud instance. I do not need IPv6 but I need to be able to connect to public IPv6. I have added a firewall rule which allows ::/0 for outgoing traffic. Now When I try to ping ipv6.google.com, it gives response- network is unreachable. What do I need to do to be able to ping any IPv6 like ipv6.google.com. Thank you.

Answer 1

Google cloud now supports external ipv6 on VM instances. Each instance can get a /96 external ip range and it can be used to access internet (without NAT) or be used for VM to VM traffic.

At this moment (July 2021) it's only supported limited regions:

• asia-east1
• asia-south1
• europe-west2
• us-west2

See more detailed in

https://cloud.google.com/compute/docs/ip-addresses/configure-ipv6-address https://cloud.google.com/vpc/docs/vpc#ipv6-addresses

Note that connecting to Google APIs and services using external IPv6 addresses is currently not supported and will result in a destination unreachable ICMP response. Most applications will fallback to IPv4 transparently. So don't be surprise if you cannot ping ipv6.google.com. You should able to ping other ipv6 websites.

Answer 2

Google Cloud now supports IPv6 for Compute Engine.

• Issue: Cannot create ICMPv6 firewall rules.

• Enabling IPv6 requires creating a new VPC. Manually create subnets - do not select auto mode for subnet creation. Existing VMs can be moved to the new VPC by changing the VPC selection in the VM edit window.

• When deploying SSL certificates using Let's Encrypt, certbot prefers to connect to the system using IPv6. Ensure that IPv6 is fully configured prior to using certbot. Or wait to configure IPv6 until after the SSL certificates are deployed.

I have deployed a production system jhanley.com using IPv4 and IPv6.

Other than those minor points, IPv6 is easy to deploy and works well.