I have a .NET 8 application which, among other things, has the following functionality: it contains a hosted service that fetches some records from a database, produces some .txt files and writes them on the path /mnt/import. The background service must run on a specified interval.

The code for the background service look like this

using Microsoft.Extensions.Hosting;

namespace ArrivalConfirmation.ExporterService.Shared.Hosting.Abstractions;

public class ScheduledBackgroundService(TimeSpan period) : BackgroundService
{
    private readonly PeriodicTimer _timer = new(period);

    public TimeSpan Period { get; } = period;

    /// <summary>Contains the logic that runs at the specified time interval.</summary>
    /// <param name="stoppingToken">Triggered when <see cref="IHostedService.StopAsync(CancellationToken)"/> is called.</param>
    /// <returns>A <see cref="ValueTask"/> representing the asynchronous operation.</returns>
    private ValueTask RunLoopAsync(CancellationToken stoppingToken) 
    {
        /* Other code removed for brevity. */
        await File.WriteAllTextAsync(path, content);
    }

    /// <summary>Calls the <see cref="RunLoopAsync(CancellationToken)"/> method at the specified time interval.</summary>
    /// <param name="stoppingToken">Triggered when <see cref="IHostedService.StopAsync(CancellationToken)"/> is called.</param>
    protected override sealed async Task ExecuteAsync(CancellationToken stoppingToken) {
        while (!stoppingToken.IsCancellationRequested && await _timer.WaitForNextTickAsync(stoppingToken)) {
            await RunLoopAsync(stoppingToken);
        }
    }

    /// <inheritdoc />
    public override void Dispose() {
        _timer.Dispose();
        base.Dispose();
    }
}

The weird thing is that when this code runs it works as expected locally, but when deployed to production, the files are written, but are lost after a short period of time.

The application runs on Azure Kuberneres Service and when deployed a docker image is used. This image is nothing special, it is just the image created from the default Dockerfile provided by Visual Studio.

On the aforementioned path, a persistent volume is mounted. I have tried to write files from the command line in k8s and the files remain after pod up or down. The even more strange thing is that when I tried to write files outside the scope of the background service the files also stay and not deleted. But when the same code runs inside a background service the files are deleted automatically after some seconds.

Does anyone have any clue what can cause this behavior? Thanks in advance.