[qianxjcraig]

Issue number:

Related: #4916, #4903

Description of changes:

Bump bottlerocket-settings-models to v0.33.0, and add migrations and defaults for:

• settings.kubernetes.merge-default-eviction-settings (feat: k8s: add merge-default-eviction-settings setting bottlerocket-settings-sdk#159, kubelet: support mergeDefaultEvictionSettings bottlerocket-core-kit#1089)
• settings.kernel.zram.size (feat: kernel: add configurable zram size bottlerocket-settings-sdk#160, corndog: support configurable boot-time zram size bottlerocket-core-kit#1093), with a zram service that re-renders corndog.toml without restarting anything

Depends on:

• A core-kit release with kubelet: support mergeDefaultEvictionSettings bottlerocket-core-kit#1089 and pubsys: template AMI names #1093
• variants: add dranet to nvidia variants #4974, which also bumps settings-models; this will be rebased on it

Testing done:

cargo test --locked --workspace passes, and the merged aws-k8s-1.35 defaults contain the zram service.

Terms of contribution:

By submitting this pull request, I agree that this contribution is dual-licensed under the terms of both the Apache License, version 2.0, and the MIT license.

[qianxjcraig]

Rebased #4991 on develop after #4974

[qianxjcraig]

Tested upgrade and downgrade on aws-k8s-1.35 (x86_64), with images built locally against core-kit from develop.

1.68.1 -> 1.69.0

$ apiclient get os.version_id
"version_id": "1.69.0"
$ journalctl -b -u migrator
migrator: Running migration 'migrate_v1.69.0_kubernetes-merge-default-eviction-settings.lz4'
migrator: Running migration 'migrate_v1.69.0_kernel-zram-size.lz4'
systemd: Finished Bottlerocket data store migrator.
$ apiclient get services.zram
{"services": {"zram": {"configuration-files": ["corndog-toml"], "restart-commands": []}}}
$ cat /sys/block/zram0/disksize
1073741824
$ systemctl is-system-running
running

1.69.0 -> 1.68.1 (after setting kernel.zram.size=512Mi and kubernetes.merge-default-eviction-settings=true)

$ apiclient get os.version_id
"version_id": "1.68.1"
$ journalctl -b -u migrator
migrator: Running migration 'migrate_v1.69.0_kernel-zram-size.lz4'
migrator: Running migration 'migrate_v1.69.0_kubernetes-merge-default-eviction-settings.lz4'
systemd: Finished Bottlerocket data store migrator.
$ apiclient get settings.kernel.zram services.zram settings.kubernetes.merge-default-eviction-settings
{}
$ systemctl is-system-running
running

1.68.1: the new settings are rejected

$ apiclient set kernel.zram.size=512Mi
Failed to change settings: ... Status 400 ... unknown field `zram`, expected one of `lockdown`, `modules`, `sysctl`, `hugepages`, `drivers`
$ apiclient set kubernetes.merge-default-eviction-settings=true
Failed to change settings: ... Status 400 ... unknown field `merge-default-eviction-settings`, expected one of `cluster-name`, ...
$ apiclient get settings.kernel.zram settings.kubernetes.merge-default-eviction-settings
{}

Rendered config, 1.68.1

$ cat /etc/corndog.toml
lockdown = "integrity"
$ grep -i evict /etc/kubernetes/kubelet/config
(no output)

Rendered config, 1.69.0 (after setting kernel.zram.size=512Mi and kubernetes.merge-default-eviction-settings=true)

$ cat /etc/corndog.toml
lockdown = "integrity"

[zram]
size = "512Mi"
$ grep mergeDefaultEvictionSettings /etc/kubernetes/kubelet/config
mergeDefaultEvictionSettings: true

[piyush-jena]

You will need another migrations for the metadata. So another rust crate with main.rs containing this:

fn run() -> Result<()> {
    migrate(AddMetadataMigration(&[SettingMetadata {
        metadata: &["affected-services"],
        setting: "settings.kernel.zram",
    }]))
}

This is because you added this in the shared-defaults:

[metadata.settings.kernel.zram]
affected-services = ["zram"]

[piyush-jena]

^

I was told that metadata migrations might not be required anymore. Can you please verify this?

[piyush-jena]

nvm I verified