# graphite() destination options

The `graphite()` destination has the following options:

## hook-commands()

_Description:_ This option makes it possible to execute external programs when the relevant driver is initialized or torn down. The `hook-commands()` can be used with all source and destination drivers with the exception of the `usertty()` and `internal()` drivers.

Note The AxoSyslog application must be able to start and restart the external program, and have the necessary permissions to do so. For example, if your host is running AppArmor or SELinux, you might have to modify your AppArmor or SELinux configuration to enable AxoSyslog to execute external applications. 

### Using `hook-commands()` when AxoSyslog starts or stops

To execute an external program when AxoSyslog starts or stops, use the following options:

#### `startup()`

Type: | string  
---|---  
Default: | N/A  
  
_Description:_ Defines the external program that is executed as AxoSyslog starts.

#### `shutdown()`

Type: | string  
---|---  
Default: | N/A  
  
_Description:_ Defines the external program that is executed as AxoSyslog stops.

### Using the hook-commands() when AxoSyslog reloads

To execute an external program when the AxoSyslog configuration is initiated or torn down, for example, on startup/shutdown or during a AxoSyslog reload, use the following options:

#### `setup()`

Type: | string  
---|---  
Default: | N/A  
  
_Description:_ Defines an external program that is executed when the AxoSyslog configuration is initiated, for example, on startup or during a AxoSyslog reload.

#### `teardown()`

Type: | string  
---|---  
Default: | N/A  
  
_Description:_ Defines an external program that is executed when the AxoSyslog configuration is stopped or torn down, for example, on shutdown or during a AxoSyslog reload.

### Example: Using hook-commands() with a network source

In the following example, the `hook-commands()` is used with the `network()` driver and it opens an [iptables](<https://en.wikipedia.org/wiki/Iptables> "https://en.wikipedia.org/wiki/Iptables") port automatically as AxoSyslog is started/stopped.

The assumption in this example is that the `LOGCHAIN` chain is part of a larger ruleset that routes traffic to it. Whenever the AxoSyslog created rule is there, packets can flow, otherwise the port is closed.
```
 
    source {
        network(transport(udp)
        hook-commands(
              startup("iptables -I LOGCHAIN 1 -p udp --dport 514 -j ACCEPT")
              shutdown("iptables -D LOGCHAIN 1")
            )
         );
    };
    
```

## host()

|   
---|---  
Type: | hostname or IP address  
Default: | localhost  
  
_Description:_ The hostname or IP address of the Graphite server.

## port()

|   
---|---  
Type: | number  
Default: | 2003  
  
_Description:_ The port number of the Graphite server.

## payload()

Type: | parameter list of the `payload()` option  
---|---  
Default: | empty string  
  
_Description:_ The payload() option allows you to select which value pairs to forward to graphite.

The syntax of `payload` is different from the syntax of `value-pairs()`: use the command-line syntax used in the [format-json template function](../../../docs/axosyslog-core/chapter-manipulating-messages/customizing-message-format/reference-template-functions/index.md). For details on using the payload() option, see [graphite-output](../../../docs/axosyslog-core/chapter-manipulating-messages/customizing-message-format/reference-template-functions/index.md).

Note If left empty, there is no data to be forwarded to Graphite. 

Last modified June 27, 2023: [Update paths to follow-up moving the files (6585a5b1)](<https://github.com/axoflow/axosyslog-core-docs/commit/6585a5b156244e39bb831bf4e8289529f30dea0f>)