# `juju config` > See also: [deploy](https://documentation.ubuntu.com/juju/4.0/reference/juju-cli/list-of-juju-cli-commands/deploy.md#command-juju-deploy), [status](https://documentation.ubuntu.com/juju/4.0/reference/juju-cli/list-of-juju-cli-commands/status.md#command-juju-status), [model-config](https://documentation.ubuntu.com/juju/4.0/reference/juju-cli/list-of-juju-cli-commands/model-config.md#command-juju-model-config), [controller-config](https://documentation.ubuntu.com/juju/4.0/reference/juju-cli/list-of-juju-cli-commands/controller-config.md#command-juju-controller-config) ## Summary Get, set, or reset configuration for a deployed application. ## Usage ```text juju config [options] [--reset ] [][=] ...] ``` ### Options | Flag | Default | Usage | |----------------------------|-----------|----------------------------------------------------------------------------| | `-B`, `--no-browser-login` | false | Do not use web browser for authentication | | `--color` | false | Use ANSI color codes in output | | `--file` | | Path to yaml-formatted configuration file | | `--format` | yaml | Specify output format (json|yaml) | | `-m`, `--model` | | Model to operate in. Accepts [:]| | | `--no-color` | false | Disable ANSI color codes in tabular output | | `-o`, `--output` | | Specify an output file | | `--reset` | | Reset the provided comma delimited keys | ## Examples To view all configuration values for an application, run ```none juju config mysql --format json ``` To set a configuration value for an application, run ```none juju config mysql foo=bar ``` To set some keys and reset others: ```none juju config mysql key1=val1 key2=val2 --reset key3,key4 ``` To set a configuration value for an application from a file: ```none juju config mysql --file=path/to/cfg.yaml ``` ## Details To view all configuration values for an application: ```none juju config ``` By default, the config will be printed in a `yaml` format. You can instead print it in a `json` format using the `--format` flag: ```none juju config --format json ``` To view the value of a single config key, run ```none juju config key ``` To set config values, run ```none juju config key1=val1 key2=val2 ... ``` This sets “key1” to “val1”, etc. Using the `@` directive, you can set a config key’s value to the contents of a file: ```none juju config key=@/tmp/configvalue ``` The maximum size of a config value read from a file this way is 5 MiB. You can also reset config keys to their default values: ```none juju config --reset key1 juju config --reset key1,key2,key3 ``` You may simultaneously set some keys and reset others: ```none juju config key1=val1 key2=val2 --reset key3,key4 ``` Config values can be imported from a yaml file using the –file flag: ```none juju config --file=path/to/cfg.yaml ``` The `yaml` file should be in the following format: ```none apache2: # application name servername: "example.com" # key1: val1 lb_balancer_timeout: 60 # key2: val2 ... ``` This allows you to, e.g., save an app’s config to a file: ```none juju config app1 > cfg.yaml ``` and then import the config later. You can also read from stdin using `-`, which allows you to pipe config values from one app to another: ```none juju config app1 | juju config app2 --file - ``` You can simultaneously read config from a yaml file and set/reset config keys as above. The command-line args will override any values specified in the file. Rather than specifying each setting name/value inline, the `--file` flag option may be used to provide a list of settings to be updated as a yaml file. The yaml file contents must include a single top-level key with the application’s name followed by a dictionary of key/value pairs that correspond to the names and values of the settings to be set. For instance, to configure apache2, the following yaml file can be used: ```none apache2: servername: "example.com" lb_balancer_timeout: 60 ``` If the above `yaml` document is stored in a file called `config.yaml`, the following command can be used to apply the config changes: ```none juju config apache2 --file config.yaml ``` Finally, the `--reset` flag can be used to revert one or more configuration settings back to their default value as defined in the charm metadata: ```none juju config apache2 --reset servername juju config apache2 --reset servername,lb_balancer_timeout ```