Overview

Commands can be sent to a single device through a direct Telnet session. However, when the same command needs to be applied across multiple Decoders, the commandallrx.sh utility provides a fast and efficient method to do so.

This command does not allow individual Decoder selection. It sends a command to multiple Decoders based on where it is executed.

Execution Behavior

The behavior of commandallrx.sh depends on where it is executed:

• Executed from an Encoder: The command is sent only to Decoders that are currently viewing that Encoder.
• Executed from a Decoder: The command is sent to all Decoders in the system.

This is useful for system-wide changes or targeting active viewing groups, but caution should be used when issuing commands that impact multiple devices.

Syntax

The commandallrx.sh script executes a command on multiple Decoders:

commandallrx.sh [command]

Where [command] is the command to be executed on each Decoder.

Command Requirements

• If the command contains spaces, it must be enclosed in double quotes.
• An ampersand (&) appended inside the quotes executes the command in the background on each Decoder. This is required for longer-running commands.
• An ampersand (&) appended outside the quotes executes the script itself in the background on the local device.

Command Examples

• Command with spaces:

  commandallrx.sh "start_image_pull 320 1 1"

• Execute the command in the background on all Decoders:

  commandallrx.sh "start_image_pull 320 1 1&"

• Execute the command in the background on all Decoders and locally:

  commandallrx.sh "start_image_pull 320 1 1&" &

How It Works

When commandallrx.sh is executed, the device performs the following sequence:

1. Run node_list locally and identify all devices labeled as JustAddPower-RX.
2. Collect the IP addresses of those devices.
3. Telnet into each device and send the command in sequence.
   • Devices are processed in the order returned by node_list.
4. Execute the command on the local device last (firmware dependent).

The results of node_list determine which Decoders receive the command:

• Encoders only list Decoders that are actively connected to them.
• Decoders list all Decoders in the system.

This is what causes the difference in execution behavior.

Considerations

The following considerations should be kept in mind when using commandallrx.sh:

• Decoder-only targeting: This script only sends commands to Decoders. Encoders cannot be targeted.
• No command chaining: The [command] cannot include a semicolon (;), preventing multiple commands from being executed in a single call.
• Background execution required for certain commands: Commands such as reboot must include an ampersand (&) to execute properly.
• Local execution may vary: Depending on firmware version, the command may not execute on the local device. If needed, execute the command locally afterward.

Common Use Cases

1. Apply a command to all Decoders in the system:

   Execute from any Decoder to broadcast the command system-wide.

   commandallrx.sh "start_image_pull 320 1 1&" &

2. Apply a command only to Decoders viewing a specific Encoder:

   Execute from the Encoder to target only the Decoders currently connected to it.

   commandallrx.sh "e e_vw_enable_0_0_0_0&"