Repository synchronization fails on Satellite with "Cannot connect to host proxy:proxy_port ssl:default [Connection reset by peer]" error

Environment

• Red Hat Satellite 6

Issue

• Repository synchronization on a Red Hat Satellite server configured to use an HTTP proxy fails, with error as follows:

  Cannot connect to host proxy:proxy_port ssl:default [Connection reset by peer]
  

Resolution

• Update the HTTP proxy configuration in Red Hat Satellite and change the proxy URL from HTTPS to HTTP as follows:

  hammer http-proxy update --name proxy_name --url http://proxy:proxy_port
  

• Alternatively, update the proxy URL from the Satellite GUI by navigating to Infrastructure > <HTTP Proxies> > Edit and changing the URL to:

  http://proxy:proxy_port
  

Reach out to Red Hat Technical Support in case this does not resolve the issue.

For more KB articles/solutions related to Red Hat Satellite 6.x Repository Issues, please refer to the Consolidated Troubleshooting Article for Red Hat Satellite 6.x Repository Issues.

Root Cause

• The proxy was configured with HTTPS, but the proxy endpoint only accepted HTTP connections. This protocol mismatch caused the SSL/TLS handshake to fail, resulting in the connection being reset by the proxy.

Diagnostic Steps

• Check /var/log/foreman/production.log for the following error, indicating a protocol mismatch where Satellite is attempting an HTTPS connection to a proxy configured for HTTP:

  2026-04-24T00:03:32 [I|bac|cbe395c5] Task {label: Actions::Katello::Repository::Sync, id: f7a3a973-3e60-4667-9cb4-8d168c384d98, execution_plan_id: 7e8afeb5-794c-47ac-bdef-6547b04ae4e0} state changed: stopped  result: warning
  2026-04-24T00:03:32 [I|app|cbe395c5] ForemanWebhooks::EventSubscriber: actions.katello.repository.sync_failed.event.foreman event received
  2026-04-24T00:03:41 [E|bac|cbe395c5] Cannot connect to host proxy:proxy_port ssl:default [Connection reset by peer] (Katello::Errors::Pulp3Error)
       cbe395c5 | /usr/share/gems/gems/katello-4.18.0.9/app/lib/actions/pulp3/abstract_async_task.rb:107:in `block in check_for_errors'
       cbe395c5 | /usr/share/gems/gems/katello-4.18.0.9/app/lib/actions/pulp3/abstract_async_task.rb:105:in `each'
       cbe395c5 | /usr/share/gems/gems/katello-4.18.0.9/app/lib/actions/pulp3/abstract_async_task.rb:105:in `check_for_errors'
       cbe395c5 | /usr/share/gems/gems/katello-4.18.0.9/app/lib/actions/pulp3/abstract_async_task.rb:161:in `poll_external_task'
  

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