3 ms·

It's surprising k8s being so new seems to have no concept of ipv6

the_duke 7y ago
It does, in alpha. Soon to hit beta though: https://github.com/kubernetes/enhancements/issues/508 https://github.com/kubernetes/enhancements/issues/508 Most internal networks still run IPv4, and will continue to do so for a long time.
sascha_sl 7y ago
Because ipv6 is not a simple addition, but a complex suite of new protocols meant to replace v4, except that is never going to happen in our lifetimes. v6 should've simply been v4 with more bits
- forgot-my-pw 7y ago
  No backwards compatibility could be IPv6's biggest mistake. Now everyone is forced to maintain 2 IP addresses.
  - gatherhunterer 7y ago
    I think that’s intended as a feature. IPv4 is just not good enough, we will run out of addresses. I think they want to kill IPv4 and replace it rather than improving upon it. At some point programs will ignore IPv4 altogether and our IP addresses will not be fundamentally flawed anymore.
    - sascha_sl 7y ago
      layers are only ever added, never removed
  - kgersen75 7y ago
    that's not true. you can have IPv6 only in the backend and expose IPv4 only at the very frontend (like Cloudfare does the other way around). Dual stack are not really needed and usually add complexity for few little benefits. The main problem of IPv6 is the lack of people willing to learn it, teach it and adopt it. Something brand new like Kubernetes should have from the start been IPv6 only , with IPv4 at the egress parts only.
  - pas 7y ago
    So far no one ever managed to come up with a plan that is backward compatible and does enough. (Aka the fundamental problem is that if you change v4 semantics you have to deploy new software/firmware/hardware, and if you are doing that anyway, a clean slate seemed like the easier option.) And don't forget v6 has well defined semantics with regards to v4 interoperability for a lot of things (::ffff:, NAT64, DNS64), so you can be on v6 and reach all of v4 via a gateway.)
- mrweasel 7y ago
  IPv6 should not be an addition to Kubernetes, but the default. IPv4 could then be an addition for when you need external communication to IPv4 networks. There's no reason why IPv6 isn't the default for internal communication between containers. We've been deploying IPv6 for at least 10 years and have hosts that are exclusively IPv6. Then along comes Docker and Kubernetes with their retro IPv4 only stack and now customer wonder why we're struggling to make containers work or suppliers that can't understand why we can't easily deploy the latest version of their software, which is only distributed as a Docker image.
  - pas 7y ago
    Well, since k8s is developed by mere humans on simple notebooks, and initially it got deployed to stock Linux they started with v4. And they had to start with v4. And to get more contributors they also needed v4. Yes, the network effects are strong with this one. But soon. Bit by bit, I hope the true dualstack will come, and then the v4 will fade away over generations.

It does, in alpha. Soon to hit beta though: https://github.com/kubernetes/enhancements/issues/508 https://github.com/kubernetes/enhancements/issues/508 Most internal networks still run IPv4, and will continue to do so for a long time.

sascha_sl 7y ago

Because ipv6 is not a simple addition, but a complex suite of new protocols meant to replace v4, except that is never going to happen in our lifetimes. v6 should've simply been v4 with more bits

forgot-my-pw 7y ago
No backwards compatibility could be IPv6's biggest mistake. Now everyone is forced to maintain 2 IP addresses.
- gatherhunterer 7y ago
  I think that’s intended as a feature. IPv4 is just not good enough, we will run out of addresses. I think they want to kill IPv4 and replace it rather than improving upon it. At some point programs will ignore IPv4 altogether and our IP addresses will not be fundamentally flawed anymore.
  - sascha_sl 7y ago
    layers are only ever added, never removed
- kgersen75 7y ago
  that's not true. you can have IPv6 only in the backend and expose IPv4 only at the very frontend (like Cloudfare does the other way around). Dual stack are not really needed and usually add complexity for few little benefits. The main problem of IPv6 is the lack of people willing to learn it, teach it and adopt it. Something brand new like Kubernetes should have from the start been IPv6 only , with IPv4 at the egress parts only.
- pas 7y ago
  So far no one ever managed to come up with a plan that is backward compatible and does enough. (Aka the fundamental problem is that if you change v4 semantics you have to deploy new software/firmware/hardware, and if you are doing that anyway, a clean slate seemed like the easier option.) And don't forget v6 has well defined semantics with regards to v4 interoperability for a lot of things (::ffff:, NAT64, DNS64), so you can be on v6 and reach all of v4 via a gateway.)
mrweasel 7y ago
IPv6 should not be an addition to Kubernetes, but the default. IPv4 could then be an addition for when you need external communication to IPv4 networks. There's no reason why IPv6 isn't the default for internal communication between containers. We've been deploying IPv6 for at least 10 years and have hosts that are exclusively IPv6. Then along comes Docker and Kubernetes with their retro IPv4 only stack and now customer wonder why we're struggling to make containers work or suppliers that can't understand why we can't easily deploy the latest version of their software, which is only distributed as a Docker image.
- pas 7y ago
  Well, since k8s is developed by mere humans on simple notebooks, and initially it got deployed to stock Linux they started with v4. And they had to start with v4. And to get more contributors they also needed v4. Yes, the network effects are strong with this one. But soon. Bit by bit, I hope the true dualstack will come, and then the v4 will fade away over generations.