Issue title: unknown service api.v1.CRIPluginService
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**Description**

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**Steps to reproduce the issue:**
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**Describe the results you received:**


**Describe the results you expected:**


**Output of `containerd --version`:**

```
(paste your output here)
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 Comments: 
 Comment 0: hi @lygstate , could you mind to provide more information here? Thanks
 Comment 1: Can you check your `/etc/containerd/config.toml`, and make sure `cri` plugin is not disabled?
 Comment 2: @Random-Liu Yeap, it's disabled, and I don't know how to open, I  am using rancheros + k3s.
 Comment 3: @lygstate Remove `cri` from the `disabled_plugins`, and restart containerd. That should help you solve the issue.
{'source': 'GithubIssues', 'repo_name_with_owner': 'containerd/containerd', 'issue_id': 421945111, 'repo_stars': 11197.0}