`apt-cache` - query the APT package cache

apt-cache madison|policy PKG

Options you will use

madison PKG: every version the configured repos offer
policy PKG: installed version, candidate, where they come from

Examples

$ apt-cache madison kubeadm

which 1.35.x patch versions exist (after apt-get update)

Gotchas

pkgs.k8s.io has one repository per minor version: to see 1.35 packages, the sources list must say /v1.35/deb/.

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