Dockershim deprecated with release of Kubernetes 1.24

Docker container runtime will no longer ship by default with K8s


The day has come. At long last Dockershim is dead.

The removal was one of several notable changes that came with today's Kubernetes 1.24 release. The shift on Dockershim has broad albeit well-documented implications for those running Kubernetes in production, James Laverack, lead solutions engineer for the release, told The Register.

The news shouldn't, however, come as a surprise, he noted. Dockershim was deprecated with Kubernetes 1.20 in late 2020.

Those affected by the change will need to do some careful planning before upgrading their clusters to the latest Kubernetes release, Laverack said. "The main takeaway for platform teams and others running Kubernetes in production is, as they make the upgrade to 1.24, they have to be aware of what container runtime they're running in their clusters, and if it's Docker, they're going to need to take some action."

The good news, he added, is this is a relatively straightforward process that has a well-documented upgrade path.

Why deprecate Dockershim?

The decision to remove Dockershim was rooted in a desire to eliminate duplicated effort and simplify the Kubernetes codebase, according to Laverack.

Previously, "the Kubernetes project had introduced a container runtime interface to allow platform teams or others to customize what container runtime they want to use," he said.

"That means that within the codebase of Kubernetes, and particularly the Kubelet, there have been two paths: one for CRI implementations and one for Docker, and this led to a lot of duplicated effort."

While the Docker CRI no longer ships with Kubernetes 1.24 or later, that doesn't mean it's no longer supported. Any number of CRIs can be deployed on version 1.24, including Docker.

The latest Kubernetes release also marks a change in philosophy surrounding which features are enabled by default. Prior to this release, beta features were enabled by default in most instances, Laverack said. With Kubernetes 1.24, "that has changed so that new APIs are now disabled by default."

This won't affect anything that's already in beta prior to version 1.24, he noted.

The change aims to discourage the use of beta features in production environments and prevent projects from staying in beta for too long, Laverack explained.

"This is really to encourage users to only build guarantees upon stable workloads that we're not going to deprecate," he said.

New features

As with previous releases, Kubernetes 1.24 adds a number of notable features and improvements.

One of the headliners is the general availability of capacity and volume expansion functionality for block storage within the Kubernetes API.

The capability, first introduced in beta with version 1.11, eliminates the need for third-party tools to indirectly manage block storage. "There have been ways to do this just by talking to the underlying storage engine. This is a way to do it through the native API," Laverack said.

"This really helps cluster administrators understand and administer storage within their clusters and also enables applications to be built on top of Kubernetes that can manage storage automatically."

Alongside the block storage enhancements, the release also adds IP collision mitigations in beta. The feature is analogous to defining a scope of IPs that can be assigned dynamically by a DHCP server. The result is users can now assign static IPs to their workloads and know for certain there won't be IP collisions because it had, unbeknownst to them, already been assigned.

And in an effort to improve supply chain security for Kubernetes clusters, version 1.24 adds an experimental support for verifying Kubernetes artifacts.

"If you are a platform team running Kubernetes you can use this to verify that what you're getting is in fact a correctly produced, untampered, unmodified version of Kubernetes," Laverack said. ®

Narrower topics


Other stories you might like

  • Stolen university credentials up for sale by Russian crooks, FBI warns
    Forget dark-web souks, thousands of these are already being traded on public bazaars

    Russian crooks are selling network credentials and virtual private network access for a "multitude" of US universities and colleges on criminal marketplaces, according to the FBI.

    According to a warning issued on Thursday, these stolen credentials sell for thousands of dollars on both dark web and public internet forums, and could lead to subsequent cyberattacks against individual employees or the schools themselves.

    "The exposure of usernames and passwords can lead to brute force credential stuffing computer network attacks, whereby attackers attempt logins across various internet sites or exploit them for subsequent cyber attacks as criminal actors take advantage of users recycling the same credentials across multiple accounts, internet sites, and services," the Feds' alert [PDF] said.

    Continue reading
  • Big Tech loves talking up privacy – while trying to kill privacy legislation
    Study claims Amazon, Apple, Google, Meta, Microsoft work to derail data rules

    Amazon, Apple, Google, Meta, and Microsoft often support privacy in public statements, but behind the scenes they've been working through some common organizations to weaken or kill privacy legislation in US states.

    That's according to a report this week from news non-profit The Markup, which said the corporations hire lobbyists from the same few groups and law firms to defang or drown state privacy bills.

    The report examined 31 states when state legislatures were considering privacy legislation and identified 445 lobbyists and lobbying firms working on behalf of Amazon, Apple, Google, Meta, and Microsoft, along with industry groups like TechNet and the State Privacy and Security Coalition.

    Continue reading
  • SEC probes Musk for not properly disclosing Twitter stake
    Meanwhile, social network's board rejects resignation of one its directors

    America's financial watchdog is investigating whether Elon Musk adequately disclosed his purchase of Twitter shares last month, just as his bid to take over the social media company hangs in the balance. 

    A letter [PDF] from the SEC addressed to the tech billionaire said he "[did] not appear" to have filed the proper form detailing his 9.2 percent stake in Twitter "required 10 days from the date of acquisition," and asked him to provide more information. Musk's shares made him one of Twitter's largest shareholders. The letter is dated April 4, and was shared this week by the regulator.

    Musk quickly moved to try and buy the whole company outright in a deal initially worth over $44 billion. Musk sold a chunk of his shares in Tesla worth $8.4 billion and bagged another $7.14 billion from investors to help finance the $21 billion he promised to put forward for the deal. The remaining $25.5 billion bill was secured via debt financing by Morgan Stanley, Bank of America, Barclays, and others. But the takeover is not going smoothly.

    Continue reading

Biting the hand that feeds IT © 1998–2022