How to Save Data Packets to an Externally Mounted Hard Drive?
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Since autonomous driving data packets recorded daily are quite large, we plan to use an external hard drive to store this data. How can this be achieved?

- Maintainer: daohu527@gmail.com
- Version: 1.0.0
- Date: 11/02/2024
- Description:

Answer
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By default, data is stored within the container. To achieve data persistence and prevent data loss, it’s necessary to mount the external hard drive to a specific directory on the host, then mount that directory into the container. This way, the data is stored on the hard drive and won’t be lost when the container stops.

Steps to Mount a Hard Drive to a Container in Ubuntu
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1. **Identify the external hard drive device**

   .. code-block:: bash

      lsblk

   Find your external hard drive device name (e.g., `/dev/sdb1`).

2. **Create a mount directory**

   Create a directory to mount the hard drive (e.g., `/apollo/data/bag`).

   .. code-block:: bash

      cd apollo
      sudo mkdir -p data/bag

3. **Mount the hard drive**

   Use the `mount` command to mount the hard drive to this directory.

   .. code-block:: bash

      sudo mount /dev/sdb1 data/bag

4. **[Skip] Start the container and mount the directory**

   When starting the container, bind the mount directory to a path within the container (e.g., `/data`).

   .. code-block:: bash

      docker run -v /mnt/external_drive:/data your_container_image

   > Since the `apollo` directory is already mounted in the container, this step can be skipped.

Thus, data on the external hard drive can be accessed within the container’s `/data` directory and will persist even if the container restarts or stops.

Recording Data Packets
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Record data packets and specify the save path.

.. code-block:: bash

   cyber_recorder record -a -o=data/bag