Advanced Guide for Checking Central Repository Status

Do This First

It's easy to confirm the status of the Central Repository.  First, check the following:

If the Central Repository is reported as available, but you are having issues downloading artifacts, there are a few possible causes. We'll order these from most likely to least likely:

1. Your Internal Network Blocks the Central Repository

This is the most common reason why someone would be unable to reach the Central Repository. Large corporations often limit outbound and inbound network traffic. If you work in such an environment, your best bet would be to discuss this matter with your own network engineers and ask them to open up access to http://repo1.maven.org or https://repo1.maven.org. If that is not effective, you can propose running a local Nexus Repository Manager instance and proxying the Central Repository from a single location in the network.

2. Central Repository is Actually Unavailable

Although it is very rare, the Central Repository has had some interruptions in the past. These days, the Central Repository is a series of machines distributed throughout the world. If the service is down for more than a handful of seconds, a distributed DNS and monitoring system immediately reroutes traffic to available nodes.

3. Blocked due to Past Violation

While this reason is very, very rare, it does happen from time to time. The Central Repository is a free, public service. Millions of developers depend on it every day as a repository for open source components. Since we're committed to making sure it is a stable, dependable resource the maintainers will sometimes have to block IP address that are abusing this free, public resource. It takes a lot a get on the radar, but if you are constantly consuming hundreds of GB s or TBs of data every month, your usage starts to limit public access to this resource.

Diagnosing Intermittent Connectivity Problems

The Central Repository is managed by a CDN. Rarely we have had issues in the past where one of the machines in our pool starts having trouble, and our service provider is slow to remove it.

If you are still experiencing this problem, please provide the following information:

  1. curl -v output when you try to get the files from Central. Example:

    curl -v -X HEAD http://repo1.maven.org/maven2/org/apache/apache/7/apache-7.pom -w "%{time_connect},%{time_starttransfer},%{size_download},%{time_total}\n"

  2. output from curl -v [http://ifconfig.co/all](http://ifconfig.me/all).json, run from the machine that's experiencing issue

  3. output from traceroute repo1.maven.org from machine with issues
  4. output from

    curl -IL http://repo1.maven.org/maven2/org/apache/apache/7/apache-7.pom

Can't download *.gz index files?

Sometimes corporate firewalls are configured to block .gz file downloads. .zip files are not published anymore for search indexes. Speak with your IT department to confirm that gz files are allowed to be downloaded.