Disable swap in a Linux environment

Below are the steps to disable swap for mostLinux distributions. If the following commands aren’t installed, you will have to install them. Consult your distributions documentation to configure swap.

1. Use the following command to check if swap is enabled:

   sudo swapon -sv

   If swap is enabled, you should see output similar to the following:

   NAME TYPE SIZE USED PRIO/dev/sda3 partition 2G 655.2M -1

2. If swap is enabled, you will have to disable it using the following processes:

   1. Disable any swap using the following command:

      sudo swapoff -av

   2. Open /etc/fstab and remove any swap partitions or files that are configured.

   3. Reboot your machine.

   4. Run the following command again ensuring there is no output:

      sudo swapoff -av

   5. If there is output, repeat Step 2, ensuring all swap files are removed from /etc/fstab.

Configure vm.swappiness in a Linux environment

Below are the steps to configure vm.swappiness for mostLinux distributions. If the following commands aren’t installed, you will have to install them. Consult your distributions documentation to configure swap.

1. Use the following command to check the value of vm.swappiness:

   sudo sysctl -n vm.swappiness

   If the value is anything other than1, it means you have some swap behavior still enabled.

2. If the swappiness value is anything except1, configure it using the following process:

   1. Open /etc/sysctl.conf and addvm.swappiness = 1 to the file on its own line.

   2. Reboot your machine.

   3. Run the following command ensuring that the output is now 1.

      sudo sysctl -n vm.swappiness

   4. If there is an output other than 1, repeat Step 2 and ensure that /etc/sysctl.conf is configured correctly.

Schedule docker images clean up

We recommend setting up a process to automatically remove docker images to avoid running out of disk space. You can create a cron job using the commanddocker system prune -af to remove all unused images. The schedule depends on the size of images you use, disk space available, and how often you run builds on a runner.

For example, do the following to clean up images once a week on Sunday at midnight:

1. Use the crontab -e command to open your user account’s crontab file.

2. Append the following entry0 0 * * 0 docker system prune -af

3. Save and close the file.

For more details, refer to the crontabdocumentation.

Starting your runner

1. Navigate to the Runners page:

   • For Workspace runners, visitWorkspace settings >Workspace runners.

   • For Repository runners, visitRepository settings >Runners.

2. SelectAdd runner.

3. From theRunner installation dialog, underSystem and architecture, selectLinux Docker (x86_64)orLinux Docker (arm64).

4. Use the pre-configured Docker command provided inRun step on theRunner installation dialogto run the runner.

   • If this is the first time running the runner, it will pull the image.

   • Before starting a new runner, always pull the runner image manually using the following command to ensure you are always running the most up-to-date runner.

     docker pull docker-public.packages.atlassian.com/sox/atlassian/bitbucket-pipelines-runner

     If you’re looking to update an existing runner to latest version, follow the instructions ofUpdating a runner version | Bitbucket Cloud | Atlassian Support

   • If you encounter the following error, run the ‘docker container rm -f runner’ command below to remove the runner.
     Error

     docker: Error response from daemon: docker: Error response from daemon: Conflict. The container name "/runner-76b247e7-b925-5e7b-9da2-1cda14c4ff2c" is already in use by container "c3403236e3af5962ed3a9b8771561bd2021974941cc8a89a40c6c66cecb18f53". You have to remove (or rename) that container to be able to reuse that name.See 'docker run --help'.

     docker container rm -f runner command

     docker container rm -f runner-76b247e7-b925-5e7b-9da2-1cda14c4ff2c

Changing the working directory of your runner

If you want to change the working directory that the runner uses on your host machine, add the following two flags to the docker run command when you start the runner:

In this command, the first value in-v parameter will be the local directory on your machine that will serve as the working directory. The second value will be the directory inside the runner. It can be anything you like, it just needs to match the value specified in theWORKING_DIRECTORY environment variable.

Access files on the host device

It's not possible to access the local files with the docker runtime. By default, the runner limits access to the host, This is to avoid pipeline failures due to dependencies on files that may not be on all machines the runners are on.

As a workaround we can suggest accessing the files on the host with an SFTP client from the Runner's build by running the following command:

For information on using the OpenSSHsftp command, visit theOpenBSD manual page server — sftp.

Using an image from an insecure Docker registry

To use an image from an insecure Docker registry on the Linux Docker runner, use acustom docker-in-docker service. For example:
dockerfile

bitbucket-pipelines.yml