Add docs on review apps disk space

1 files changed, 51 insertions, 0 deletions

diff --git a/doc/maintenance.md b/doc/maintenance.md
index b096275b..ef8636a7 100644
--- a/doc/maintenance.md
+++ b/doc/maintenance.md
@@ -165,3 +165,54 @@ Instead, we use a YAML file which is then converted into the `_redirects` file:
 1. The [Rake task creates `public/_redirects`](https://gitlab.com/gitlab-org/gitlab-docs/-/blob/4fc73c9a5f1652cc2e0b284bfe1e937887a37183/Rakefile#L217-231) by parsing `redirects.yaml`.
 1. After Pages deploys the site, the `_redirects` file is at <https://docs.gitlab.com/_redirects>,
    and the redirects should be working.
+
+## Review apps
+
+The review apps server is hosted in GCP using the [sandbox](https://about.gitlab.com/handbook/infrastructure-standards/realms/sandbox/)
+service provided by GitLab's infrastructure team. It is running Debian 11, and
+it has 100GB of space.
+
+The current owners of the GCP project are:
+
+- Amy
+- Axil
+- Evan
+- Marcel
+- Marcin
+
+If you need access, ask one of the above people to [add you to the owners](https://console.cloud.google.com/iam-admin/iam?project=axil-635e068f).
+
+### Delete old review apps when there is not enough disk space
+
+Each review app takes about 2.5GB of disk space.
+Sometimes the review app server is full and there is no more disk space.
+A cron job to remove review apps older than 14 days runs hourly,
+but the disk space still occasionally fills up.
+
+To manually free up more space, an owner of the GCP project can:
+
+1. Navigate to the [GCP VM daashboard](https://console.cloud.google.com/compute/instances?project=axil-635e068f).
+1. Select the SSH button to connect to the VM through your browaser.
+1. Run the `clean-pages` script by providing it the number of days:
+
+   ```shell
+   sudo -u gitlab-runner /home/gitlab-runner/clean-pages 10
+   ```
+
+There's an issue to [migrate from the DigitalOcean server to GCP buckets](https://gitlab.com/gitlab-org/gitlab-docs/-/issues/735)),
+which should solve the disk space problem.
+
+See [this issue](https://gitlab.com/gitlab-org/gitlab-docs/-/issues/1152) for
+more information.
+
+### Resize review apps disk space
+
+If the disk space is still running low, you can resize it:
+
+1. Go to the [disk page](https://console.cloud.google.com/compute/disksDetail/zones/us-central1-a/disks/docs-review-apps?project=axil-635e068f)
+1. Select **Edit**.
+1. Fill in the new size in GB.
+1. Select **Save**.
+1. Reboot the VM.
+
+See the [official GCP documentation](https://cloud.google.com/compute/docs/disks/resize-persistent-disk).