--- title: Charmhub | Deploy Operator Libs Linux using Charmhub - The Open Operator Collection description: Deploy the latest version of Operator Libs Linux on any cloud. url: https://charmhub.io/operator-libs-linux/libraries/grub --- # Operator Libs Linux [Jon Seager](https://charmhub.io/publisher/jnsgruk "View all packages from Jon Seager") * [Jon Seager](https://charmhub.io/publisher/jnsgruk "View all packages from Jon Seager") Platform: 22.04 20.04 stable 2 ``` juju deploy operator-libs-linux ``` [Learn to deploy on juju >](https://juju.is/docs/juju/manage-applications) [Toggle side navigation](https://charmhub.io/operator-libs-linux/libraries/grub#drawer) ## charms.operator\_libs\_linux.v0.grub * [*Docstrings*Docstrings](https://charmhub.io/operator-libs-linux/libraries/grub) [*Code*Source code](https://charmhub.io/operator-libs-linux/libraries/grub/source-code) * + Download Fetch library ``` charmcraft fetch-lib charms.operator_libs_linux.v0.grub ``` [Download grub.py](https://charmhub.io/operator-libs-linux/libraries/grub/download) + *Last updated* 31 Aug 2023 + *Revision* Library version 0.3 Simple library for managing Linux kernel configuration via GRUB. This library is only used for setting additional parameters that will be stored in the "/etc/default/grub.d/95-juju-charm.cfg" config file and not for editing other configuration files. It's intended to be used in charms to help configure the machine. Configurations for individual charms will be stored in "/etc/default/grub.d/90-juju-", but these configurations will only have informational value as all configurations will be merged to "/etc/default/grub.d/95-juju-charm.cfg". Example of use: ``` class UbuntuCharm(CharmBase): def __init__(self, *args): ... self.framework.observe(self.on.install, self._on_install) self.framework.observe(self.on.update_status, self._on_update_status) self.framework.observe(self.on.remove, self._on_remove) self.grub = grub.GrubConfig(self.meta.name) log.debug("found keys %s in GRUB config file", self.grub.keys()) def _on_install(self, _): try: self.grub.update( {"GRUB_CMDLINE_LINUX_DEFAULT": "$GRUB_CMDLINE_LINUX_DEFAULT hugepagesz=1G"} ) except grub.ValidationError as error: self.unit.status = BlockedStatus(f"[{error.key}] {error.message}") def _on_update_status(self, _): if self.grub["GRUB_CMDLINE_LINUX_DEFAULT"] != "$GRUB_CMDLINE_LINUX_DEFAULT hugepagesz=1G": self.unit.status = BlockedStatus("wrong GRUB configuration") def _on_remove(self, _): self.grub.remove() ``` --- Index * [class ValidationError](https://charmhub.io/operator-libs-linux/libraries/grub#validationerror) * + [def \_\_init\_\_( self, key, message)](https://charmhub.io/operator-libs-linux/libraries/grub#validationerror-__init__) * + [def \_\_str\_\_( self)](https://charmhub.io/operator-libs-linux/libraries/grub#validationerror-__str__) * [class IsContainerError](https://charmhub.io/operator-libs-linux/libraries/grub#iscontainererror) * [class ApplyError](https://charmhub.io/operator-libs-linux/libraries/grub#applyerror) * [def check\_update\_grub( )](https://charmhub.io/operator-libs-linux/libraries/grub#check_update_grub) * [def is\_container( )](https://charmhub.io/operator-libs-linux/libraries/grub#is_container) * [class Config](https://charmhub.io/operator-libs-linux/libraries/grub#config) * + [def \_\_init\_\_( self, charm\_name)](https://charmhub.io/operator-libs-linux/libraries/grub#config-__init__) * + [def \_\_contains\_\_( self, key)](https://charmhub.io/operator-libs-linux/libraries/grub#config-__contains__) * + [def \_\_len\_\_( self)](https://charmhub.io/operator-libs-linux/libraries/grub#config-__len__) * + [def \_\_iter\_\_( self)](https://charmhub.io/operator-libs-linux/libraries/grub#config-__iter__) * + [def \_\_getitem\_\_( self, key)](https://charmhub.io/operator-libs-linux/libraries/grub#config-__getitem__) * + [def applied\_configs( self)](https://charmhub.io/operator-libs-linux/libraries/grub#config-applied_configs) * + [def blocked\_keys( self)](https://charmhub.io/operator-libs-linux/libraries/grub#config-blocked_keys) * + [def charm\_name( self)](https://charmhub.io/operator-libs-linux/libraries/grub#config-charm_name) * + [def path( self)](https://charmhub.io/operator-libs-linux/libraries/grub#config-path) * + [def apply( self)](https://charmhub.io/operator-libs-linux/libraries/grub#config-apply) * + [def remove( self, apply)](https://charmhub.io/operator-libs-linux/libraries/grub#config-remove) * + [def update( self, config, apply)](https://charmhub.io/operator-libs-linux/libraries/grub#config-update) #### class ValidationError Description Exception representing value validation error. None Methods ValidationError. \_\_init\_\_( *self* , key: str , message: str ) ValidationError. \_\_str\_\_( *self* ) Description Return string representation of error. None #### class IsContainerError Description Exception if local machine is container. None #### class ApplyError Description Exception if applying new config failed. None #### def check\_update\_grub() Description Report whether an update to /boot/grub/grub.cfg is available. None #### def is\_container() Description Report whether the local machine is a container. None #### class Config Manages GRUB configuration. Description This object will load current configuration option for GRUB and provide option to update it with simple validation, remove charm option and apply those changes. Methods Config. \_\_init\_\_( *self* , charm\_name: str ) Description Initialize the GRUB config. None Config. \_\_contains\_\_( *self* , key: str ) Description Check if key is in config. None Config. \_\_len\_\_( *self* ) Description Get size of config. None Config. \_\_iter\_\_( *self* ) Description Iterate over config. None Config. \_\_getitem\_\_( *self* , key: str ) Description Get value for key form config. None Config. applied\_configs( *self* ) Description Return list of charms configs which registered config in LIB\_CONFIG\_DIRECTORY. None Config. blocked\_keys( *self* ) Description Get set of configured keys by other charms. None Config. charm\_name( *self* ) Description Get charm name or use value obtained from JUJU\_UNIT\_NAME env. None Config. path( *self* ) Description Return path for charm config. None Config. apply( *self* ) Description Check if an update to /boot/grub/grub.cfg is available. None Config. remove( *self* , apply: bool ) Remove config for charm. Description This function will remove config file for charm and re-create the `95-juju-charm.cfg` GRUB config file without changes made by this charm. Config. update( *self* , config , apply: bool ) Description Update the Grub configuration. None