Add documentation for configuring nat outgoing ipv6

[anders-elastisys]

What type of PR is this?

/kind documentation

What this PR does / why we need it:

The variable nat_outgoing_ipv6 is not documented anywhere, and it needs to be enabled if you want outgoing ipv6 traffic from pods.

Also fixed the value set for calico_vxlan_mode_ipv6.

Which issue(s) this PR fixes:

Fixes #

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

Add documentation for configuring nat outgoing ipv6

[k8s-ci-robot]

Hi @anders-elastisys. Thanks for your PR.

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[VannTen]

We should rather add the value alongside nat_outgoing in roles/network_plugin/calico_defaults/defaults/main.yml, I think

[anders-elastisys]

@VannTen have it in both? The reason for this PR is to have it documented somewhere, preferably in a markdown file so that is easier to find and to know how to configure. But I agree, it should be defined in the role as well, I will add it.

[VannTen]

On Thu, Feb 01, 2024 at 06:34:56AM -0800, anders-elastisys wrote: @VannTen have it in both? The reason for this PR is to have it documented somewhere, preferably in a markdown file so that is easier to find and to know how to configure. But I agree, it should be defined in the role as well, I will add it.

Well in that case the comment in yaml and the markdown says essentially the same thing (duplication tends to bother me a bit^). My opinion is that we should have "guides" in docs/ and the defaults roles should be automatically assembled into a "reference" documentation (see #10697) ; but it's not exactly that way currently. Oh well. /lgtm

[yankay]

/ok-to-test

[VannTen]

/lgtm
@anders-elastisys please add NONE in the changelog entry in the PR description so it will be correctly classified by the release script
/hold
/assign @yankay
(for approval)

[cyclinder]

Thanks， Can you also add this to inventory/sample/group_vars/k8s_cluster/k8s-net-calico.yml?

# Enables Internet connectivity from containers
# nat_outgoing: true
# nat_outgoing_ipv6: false

[anders-elastisys]

@cyclinder added now, PTAL

[VannTen]

/hold cancel

[cyclinder]

Thanks

/lgtm

[yankay]

Thanks @anders-elastisys @VannTen @cyclinder
/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: anders-elastisys, yankay

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