Red Hat Summit13.3.7. Bare-metal node maintenance
You can connect to a node for general troubleshooting. However, in some cases, you need to perform troubleshooting or maintenance tasks on certain hardware components. This section discusses topics that you need to perform for hardware maintenance.
13.3.7.1. Connecting to a bare-metal node in your cluster
You can connect to bare-metal cluster nodes for general maintenance tasks.
Configuring the cluster node from the host operating system is not recommended or supported.
To troubleshoot your nodes, you can do the following tasks:
- Retrieve logs from a node
- Use debugging
- Use SSH to connect to a node
Use SSH only if you cannot connect to the node with the oc debug command.
Procedure
Retrieve the logs from a node by running the following command:
$ oc adm node-logs <node_name> -u crioUse debugging by running the following command:
$ oc debug node/<node_name>Set
/hostas the root directory within the debug shell. The debug pod mounts the host’s root file system in/hostwithin the pod. By changing the root directory to/host, you can run binaries contained in the host’s executable paths:# chroot /hostYou are now logged in as root on the node.
Optional: Use SSH to connect to the node by running the following command:
$ ssh core@<node_name>
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