extension-host

README

Steadybit extension-host

This Steadybit extension provides a host discovery and various actions for host targets.

Learn about the capabilities of this extension in our Reliability Hub.

Configuration

Environment Variable	Helm value	Meaning	Required	Default
STEADYBIT_LABEL_<key>=<value>		Environment variables starting with STEADYBIT_LABEL_ will be added to discovered targets' attributes. Example: STEADYBIT_LABEL_TEAM=Fullfillment adds to each discovered target the attribute team=Fullfillment	no
STEADYBIT_DISCOVERY_ENV_LIST		List of environment variables to be evaluated and added to discovered targets' attributes. Example: STEADYBIT_DISCOVERY_ENV_LIST=STAGE adds to each target the attribute stage=<value of $STAGE>	no
STEADYBIT_EXTENSION_DISCOVERY_ATTRIBUTES_EXCLUDES_HOST	discovery.attributes.excludes.host	List of Target Attributes which will be excluded during discovery. Checked by key equality and supporting trailing "*"	false

The extension supports all environment variables provided by steadybit/extension-kit.

When installed as linux package this configuration is in/etc/steadybit/extension-host.

Needed capabilities

The capabilities needed by this extension are: (which are provided by the helm chart)

• SYS_ADMIN
• SYS_RESOURCE
• SYS_BOOT
• NET_RAW
• SYS_TIME
• SYS_PTRACE
• KILL
• NET_ADMIN
• DAC_OVERRIDE
• SETUID
• SETGID
• AUDIT_WRITE

Installation

Using Helm in Kubernetes

helm repo add steadybit-extension-host https://steadybit.github.io/extension-host
helm repo update
helm upgrade steadybit-extension-host \
    --install \
    --wait \
    --timeout 5m0s \
    --create-namespace \
    --namespace steadybit-agent \
    steadybit-extension-host/steadybit-extension-host

Using Docker

This extension is by default deployed using our agent.sh docker compose script.

Or you can run it manually:

docker run \
  --rm \
  -p 8085:8085 \
  --name steadybit-extension-host \
  --privileged
  --network=host
  --pid=host
  ghcr.io/steadybit/extension-host:latest

Linux Package

Please use our agent-linux.sh script to install the extension on your Linux machine. The script will download the latest version of the extension and install it using the package manager.

Register the extension

Make sure to register the extension at the steadybit platform. Please refer to the documentation for more information.

Troubleshooting

When the host is using cgorups v2 and the cgroup filesystem is mounted using the nsdelegate option will prevent that the action running processces in other cgroups (e.g. stress cpu/memory, disk fill) will fail. In that case you need to remount the cgroup filesystem without the nsdelegate option.

sudo mount -o remount,rw,nosuid,nodev,noexec,relatime -t cgroup2 none /sys/fs/cgroup