248 lines
12 KiB
Markdown
248 lines
12 KiB
Markdown
# CRI Plugin Config Guide
|
|
This document provides the description of the CRI plugin configuration.
|
|
The CRI plugin config is part of the containerd config (default
|
|
path: `/etc/containerd/config.toml`).
|
|
|
|
See [here](https://github.com/containerd/containerd/blob/master/docs/ops.md)
|
|
for more information about containerd config.
|
|
|
|
The explanation and default value of each configuration item are as follows:
|
|
```toml
|
|
# Use config version 2 to enable new configuration fields.
|
|
# Config file is parsed as version 1 by default.
|
|
version = 2
|
|
|
|
# The 'plugins."io.containerd.grpc.v1.cri"' table contains all of the server options.
|
|
[plugins."io.containerd.grpc.v1.cri"]
|
|
|
|
# disable_tcp_service disables serving CRI on the TCP server.
|
|
# Note that a TCP server is enabled for containerd if TCPAddress is set in section [grpc].
|
|
disable_tcp_service = true
|
|
|
|
# stream_server_address is the ip address streaming server is listening on.
|
|
stream_server_address = "127.0.0.1"
|
|
|
|
# stream_server_port is the port streaming server is listening on.
|
|
stream_server_port = "0"
|
|
|
|
# stream_idle_timeout is the maximum time a streaming connection can be
|
|
# idle before the connection is automatically closed.
|
|
# The string is in the golang duration format, see:
|
|
# https://golang.org/pkg/time/#ParseDuration
|
|
stream_idle_timeout = "4h"
|
|
|
|
# enable_selinux indicates to enable the selinux support.
|
|
enable_selinux = false
|
|
|
|
# sandbox_image is the image used by sandbox container.
|
|
sandbox_image = "k8s.gcr.io/pause:3.1"
|
|
|
|
# stats_collect_period is the period (in seconds) of snapshots stats collection.
|
|
stats_collect_period = 10
|
|
|
|
# enable_tls_streaming enables the TLS streaming support.
|
|
# It generates a self-sign certificate unless the following x509_key_pair_streaming are both set.
|
|
enable_tls_streaming = false
|
|
|
|
# 'plugins."io.containerd.grpc.v1.cri".x509_key_pair_streaming' contains a x509 valid key pair to stream with tls.
|
|
[plugins."io.containerd.grpc.v1.cri".x509_key_pair_streaming]
|
|
# tls_cert_file is the filepath to the certificate paired with the "tls_key_file"
|
|
tls_cert_file = ""
|
|
|
|
# tls_key_file is the filepath to the private key paired with the "tls_cert_file"
|
|
tls_key_file = ""
|
|
|
|
# max_container_log_line_size is the maximum log line size in bytes for a container.
|
|
# Log line longer than the limit will be split into multiple lines. -1 means no
|
|
# limit.
|
|
max_container_log_line_size = 16384
|
|
|
|
# disable_cgroup indicates to disable the cgroup support.
|
|
# This is useful when the daemon does not have permission to access cgroup.
|
|
disable_cgroup = false
|
|
|
|
# disable_apparmor indicates to disable the apparmor support.
|
|
# This is useful when the daemon does not have permission to access apparmor.
|
|
disable_apparmor = false
|
|
|
|
# restrict_oom_score_adj indicates to limit the lower bound of OOMScoreAdj to
|
|
# the containerd's current OOMScoreAdj.
|
|
# This is useful when the containerd does not have permission to decrease OOMScoreAdj.
|
|
restrict_oom_score_adj = false
|
|
|
|
# max_concurrent_downloads restricts the number of concurrent downloads for each image.
|
|
max_concurrent_downloads = 3
|
|
|
|
# disable_proc_mount disables Kubernetes ProcMount support. This MUST be set to `true`
|
|
# when using containerd with Kubernetes <=1.11.
|
|
disable_proc_mount = false
|
|
|
|
# 'plugins."io.containerd.grpc.v1.cri".containerd' contains config related to containerd
|
|
[plugins."io.containerd.grpc.v1.cri".containerd]
|
|
|
|
# snapshotter is the snapshotter used by containerd.
|
|
snapshotter = "overlayfs"
|
|
|
|
# no_pivot disables pivot-root (linux only), required when running a container in a RamDisk with runc.
|
|
# This only works for runtime type "io.containerd.runtime.v1.linux".
|
|
no_pivot = false
|
|
|
|
# default_runtime_name is the default runtime name to use.
|
|
default_runtime_name = "runc"
|
|
|
|
# 'plugins."io.containerd.grpc.v1.cri".containerd.default_runtime' is the runtime to use in containerd.
|
|
# DEPRECATED: use `default_runtime_name` and `plugins."io.containerd.grpc.v1.cri".runtimes` instead.
|
|
# Remove in containerd 1.4.
|
|
[plugins."io.containerd.grpc.v1.cri".containerd.default_runtime]
|
|
|
|
# 'plugins."io.containerd.grpc.v1.cri".containerd.untrusted_workload_runtime' is a runtime to run untrusted workloads on it.
|
|
# DEPRECATED: use `untrusted` runtime in `plugins."io.containerd.grpc.v1.cri".runtimes` instead.
|
|
# Remove in containerd 1.4.
|
|
[plugins."io.containerd.grpc.v1.cri".containerd.untrusted_workload_runtime]
|
|
|
|
# 'plugins."io.containerd.grpc.v1.cri".containerd.runtimes' is a map from CRI RuntimeHandler strings, which specify types
|
|
# of runtime configurations, to the matching configurations.
|
|
# In this example, 'runc' is the RuntimeHandler string to match.
|
|
[plugins."io.containerd.grpc.v1.cri".containerd.runtimes.runc]
|
|
# runtime_type is the runtime type to use in containerd e.g. io.containerd.runtime.v1.linux
|
|
runtime_type = "io.containerd.runc.v1"
|
|
|
|
# pod_annotations is a list of pod annotations passed to both pod
|
|
# sandbox as well as container OCI annotations. Pod_annotations also
|
|
# supports golang path match pattern - https://golang.org/pkg/path/#Match.
|
|
# e.g. ["runc.com.*"], ["*.runc.com"], ["runc.com/*"].
|
|
#
|
|
# For the naming convention of annotation keys, please reference:
|
|
# * Kubernetes: https://kubernetes.io/docs/concepts/overview/working-with-objects/annotations/#syntax-and-character-set
|
|
# * OCI: https://github.com/opencontainers/image-spec/blob/master/annotations.md
|
|
pod_annotations = []
|
|
|
|
# container_annotations is a list of container annotations passed through to the OCI config of the containers.
|
|
# Container annotations in CRI are usually generated by other Kubernetes node components (i.e., not users).
|
|
# Currently, only device plugins populate the annotations.
|
|
container_annotations = []
|
|
|
|
# privileged_without_host_devices allows overloading the default behaviour of passing host
|
|
# devices through to privileged containers. This is useful when using a runtime where it does
|
|
# not make sense to pass host devices to the container when privileged. Defaults to false -
|
|
# i.e pass host devices through to privileged containers.
|
|
privileged_without_host_devices = false
|
|
|
|
# 'plugins."io.containerd.grpc.v1.cri".containerd.runtimes.runc.options' is options specific to
|
|
# "io.containerd.runc.v1". Its corresponding options type is:
|
|
# https://github.com/containerd/containerd/blob/v1.2.0-rc.1/runtime/v2/runc/options/oci.pb.go#L39.
|
|
[plugins."io.containerd.grpc.v1.cri".containerd.runtimes.runc.options]
|
|
# NoPivotRoot disables pivot root when creating a container.
|
|
NoPivotRoot = false
|
|
|
|
# NoNewKeyring disables new keyring for the container.
|
|
NoNewKeyring = false
|
|
|
|
# ShimCgroup places the shim in a cgroup.
|
|
ShimCgroup = ""
|
|
|
|
# IoUid sets the I/O's pipes uid.
|
|
IoUid = 0
|
|
|
|
# IoGid sets the I/O's pipes gid.
|
|
IoGid = 0
|
|
|
|
# BinaryName is the binary name of the runc binary.
|
|
BinaryName = ""
|
|
|
|
# Root is the runc root directory.
|
|
Root = ""
|
|
|
|
# CriuPath is the criu binary path.
|
|
CriuPath = ""
|
|
|
|
# SystemdCgroup enables systemd cgroups.
|
|
SystemdCgroup = false
|
|
|
|
# 'plugins."io.containerd.grpc.v1.cri".cni' contains config related to cni
|
|
[plugins."io.containerd.grpc.v1.cri".cni]
|
|
# bin_dir is the directory in which the binaries for the plugin is kept.
|
|
bin_dir = "/opt/cni/bin"
|
|
|
|
# conf_dir is the directory in which the admin places a CNI conf.
|
|
conf_dir = "/etc/cni/net.d"
|
|
|
|
# max_conf_num specifies the maximum number of CNI plugin config files to
|
|
# load from the CNI config directory. By default, only 1 CNI plugin config
|
|
# file will be loaded. If you want to load multiple CNI plugin config files
|
|
# set max_conf_num to the number desired. Setting max_config_num to 0 is
|
|
# interpreted as no limit is desired and will result in all CNI plugin
|
|
# config files being loaded from the CNI config directory.
|
|
max_conf_num = 1
|
|
|
|
# conf_template is the file path of golang template used to generate
|
|
# cni config.
|
|
# If this is set, containerd will generate a cni config file from the
|
|
# template. Otherwise, containerd will wait for the system admin or cni
|
|
# daemon to drop the config file into the conf_dir.
|
|
# This is a temporary backward-compatible solution for kubenet users
|
|
# who don't have a cni daemonset in production yet.
|
|
# This will be deprecated when kubenet is deprecated.
|
|
# See the "CNI Config Template" section for more details.
|
|
conf_template = ""
|
|
|
|
# 'plugins."io.containerd.grpc.v1.cri".registry' contains config related to the registry
|
|
[plugins."io.containerd.grpc.v1.cri".registry]
|
|
|
|
# 'plugins."io.containerd.grpc.v1.cri".registry.mirrors' are namespace to mirror mapping for all namespaces.
|
|
[plugins."io.containerd.grpc.v1.cri".registry.mirrors]
|
|
[plugins."io.containerd.grpc.v1.cri".registry.mirrors."docker.io"]
|
|
endpoint = ["https://registry-1.docker.io", ]
|
|
```
|
|
|
|
## Untrusted Workload
|
|
|
|
The recommended way to run untrusted workload is to use
|
|
[`RuntimeClass`](https://kubernetes.io/docs/concepts/containers/runtime-class/) api
|
|
introduced in Kubernetes 1.12 to select RuntimeHandlers configured to run
|
|
untrusted workload in `plugins."io.containerd.grpc.v1.cri".containerd.runtimes`.
|
|
|
|
However, if you are using the legacy `io.kubernetes.cri.untrusted-workload`pod annotation
|
|
to request a pod be run using a runtime for untrusted workloads, the RuntimeHandler
|
|
`plugins."io.containerd.grpc.v1.cri"cri.containerd.runtimes.untrusted` must be defined first.
|
|
When the annotation `io.kubernetes.cri.untrusted-workload` is set to `true` the `untrusted`
|
|
runtime will be used. For example, see
|
|
[Create an untrusted pod using Kata Containers](https://github.com/kata-containers/documentation/blob/master/how-to/how-to-use-k8s-with-cri-containerd-and-kata.md#create-an-untrusted-pod-using-kata-containers).
|
|
|
|
## CNI Config Template
|
|
|
|
Ideally the cni config should be placed by system admin or cni daemon like calico,
|
|
weaveworks etc. However, there are still users using [kubenet](https://kubernetes.io/docs/concepts/cluster-administration/network-plugins/#kubenet)
|
|
today, who don't have a cni daemonset in production. The cni config template is
|
|
a temporary backward-compatible solution for them. This is expected to be
|
|
deprecated when kubenet is deprecated.
|
|
|
|
The cni config template uses the [golang
|
|
template](https://golang.org/pkg/text/template/) format. Currently supported
|
|
values are:
|
|
* `.PodCIDR` is a string of the first CIDR assigned to the node.
|
|
* `.PodCIDRRanges` is a string array of all CIDRs assigned to the node. It is
|
|
usually used for
|
|
[dualstack](https://github.com/kubernetes/enhancements/blob/master/keps/sig-network/20180612-ipv4-ipv6-dual-stack.md) support.
|
|
* `.Routes` is a string array of all routes needed. It is usually used for
|
|
dualstack support or single stack but IPv4 or IPv6 is decided at runtime.
|
|
|
|
The [golang template actions](https://golang.org/pkg/text/template/#hdr-Actions)
|
|
can be used to render the cni config. For example, you can use the following
|
|
template to add CIDRs and routes for dualstack in the CNI config:
|
|
```
|
|
"ipam": {
|
|
"type": "host-local",
|
|
"ranges": [{{range $i, $range := .PodCIDRRanges}}{{if $i}}, {{end}}[{"subnet": "{{$range}}"}]{{end}}],
|
|
"routes": [{{range $i, $route := .Routes}}{{if $i}}, {{end}}{"dst": "{{$route}}"}{{end}}]
|
|
}
|
|
```
|
|
|
|
## Deprecation
|
|
The config options of the CRI plugin follow the [Kubernetes deprecation
|
|
policy of "admin-facing CLI components"](https://kubernetes.io/docs/reference/using-api/deprecation-policy/#deprecating-a-flag-or-cli).
|
|
|
|
In summary, when a config option is announced to be deprecated:
|
|
* It is kept functional for 6 months or 1 release (whichever is longer);
|
|
* A warning is emitted when it is used.
|