'Connection reset by peer' error while mirroring repositories

Description

Users encounter a "Connection reset by peer" error when attempting to mirror repositories in GitLab

Environment

• no_proxy configuration includes port numbers in URLs

• Impacted offerings:

  • GitLab Dedicated
  • GitLab Self-Managed

• Impacted versions:

  • All current versions

Solution OR Workaround

1. Check your no_proxy configuration settings for any URLs that include port numbers
2. Remove the port numbers from those URLs in the no_proxy configuration
3. Restart GitLab services if necessary

Cause

When the no_proxy configuration contains URLs with port numbers, it interferes with DNS resolution. This causes the connection to be reset when attempting to mirror repositories, resulting in the "Connection reset by peer" error.

Additional information

• Based on testing, the http_proxy and https_proxy works fine when adding port numbers to the URLs

Related links

• GitLab Documentation on Repository Mirroring
• Setting custom environment variables