CLI Kernel Management

This is a list of kernel tasks to perform with the MAAS CLI. See MAAS CLI on how to get started. These resources will also be helpful:

• Ubuntu kernels for background on Ubuntu kernels within a MAAS context.
• Kernel boot options for help on kernel boot options.

Set the default kernel boot options

To set kernel boot options that will be applied to all machines:

maas $PROFILE maas set-config name=kernel_opts value='$KERNEL_OPTIONS'

Specify kernel boot options for a machine

To specify kernel boot options for an individual machine a tag needs to be created:

maas $PROFILE tags create name='$TAG_NAME' \
    comment='$COMMENT' kernel_opts='$KERNEL_OPTIONS'

For example:

maas $PROFILE tags create name='nomodeset' \
    comment='nomodeset kernel option' kernel_opts='nomodeset vga'

The tag must then be assigned to the machine in question. This can be done with the web UI or with the CLI. For the latter, see CLI - Manual tag assignment.

If multiple tags attached to a node have the kernel_opts defined, the first one (ordered alphabetically) is used.

Set a default minimum kernel for enlistment and commissioning

To set a default minimum kernel for all new and commissioned machines:

maas $PROFILE maas set-config name=default_min_hwe_kernel value=$KERNEL

For example, to set it to the 16.04 GA kernel:

maas $PROFILE maas set-config name=default_min_hwe_kernel value=ga-16.04

Set a minimum deploy kernel for a machine

To set the minimum deploy kernel on a per machine basis:

maas $PROFILE machine update $SYSTEM_ID min_hwe_kernel=$HWE_KERNEL

For example, to set it to the HWE 16.04 kernel:

maas $PROFILE machine update $SYSTEM_ID min_hwe_kernel=hwe-16.04

Set a specific kernel during machine deployment

To set a specific kernel during the deployment of a machine:

maas $PROFILE machine deploy $SYSTEM_ID distro_series=$SERIES hwe_kernel=$KERNEL

The operation will fail if the kernel specified by hwe_kernel is older than the kernel (possibly) given by default_min_hwe_kernel. Similarly, it will not work if the kernel is simply not available for the given distro series (such as 'hwe-16.10' for 'xenial').

For example, to deploy a Xenial node with the HWE 16.04 edge kernel:

maas $PROFILE machine deploy $SYSTEM_ID distro_series=xenial hwe_kernel=hwe-16.04-edge