pppoe-stop

pppoe-stop

`pppoe-stop` is a utility provided as part of the `rp-pppoe` (Roaring Penguin PPPoE) client suite for Linux. Its primary function is to gracefully terminate an active Point-to-Point Protocol over Ethernet (PPPoE) broadband internet connection previously established using commands like `pppoe-start`.

When invoked, `pppoe-stop` typically performs the following actions:

1. Identify Running Process: It locates the Process ID (PID) of the `pppoe` daemon or the `pppoe-connect` script that is currently managing the active connection. This is often done by reading a PID file, commonly located at `/var/run/pppoe-connect.pid` or `/var/run/pppoe.pid`.
2. Send Termination Signal: It sends a termination signal (usually `SIGTERM`) to the identified process, requesting it to shut down cleanly.
3. Force Kill (if necessary): If the process does not respond to the `SIGTERM` within a reasonable timeout, `pppoe-stop` may send a more forceful `SIGKILL` signal to ensure the process is terminated.
4. Cleanup: It ensures that the network interface associated with the PPPoE connection is properly brought down, and any temporary files or resources allocated by the connection are released.

This command is essential for users to manage their broadband connections, allowing them to disconnect when necessary, freeing up network resources and the public IP address. Due to its interaction with network interfaces and system processes, `pppoe-stop` usually requires root privileges to execute successfully.

1. Root Privileges: Requires root privileges or `sudo` to execute, as it interacts with system-level processes and network interfaces.
2. PID File Dependency: Its success heavily depends on the presence and correctness of the PID file (e.g., `/var/run/pppoe-connect.pid`). If this file is missing, corrupt, or contains an incorrect PID, `pppoe-stop` may fail to identify and terminate the running connection.
3. Single Connection: Typically designed to stop the one active PPPoE connection managed by `pppoe-start`. If multiple complex PPPoE configurations are running (which is uncommon with `rp-pppoe`), this command might only affect the primary one.
4. Wrapper Script: `pppoe-stop` is often a high-level shell script that calls underlying system commands (`kill`, `rm`). Problems can arise if these underlying commands fail or if the environment is unexpected.

Due to its system-level operations, `pppoe-stop` must almost always be run with `sudo` privileges: `sudo pppoe-stop`.

The command typically looks for the PID of the running `pppoe-connect` process in a file like `/var/run/pppoe-connect.pid`. Ensure this file is present and valid for the command to function correctly.

The `pppoe-stop` command is an integral part of the Roaring Penguin PPPoE client (rp-pppoe) suite, which gained prominence in the early 2000s. It was developed to provide a straightforward command-line interface for managing PPPoE connections on Linux systems, a common method for broadband internet access (especially ADSL) at the time. Its development paralleled the widespread adoption of PPPoE, offering a robust and reliable way to initiate and terminate these connections from the command line, complementing the `pppoe-start` command.

pppoe-start(8), pppoe-connect(8), pppoe(8), pppd(8), ifconfig(8), ip(8)