Homebrew SSL_connect Error: SSL_ERROR_SYSCALL in connection to raw.githubusercontent.com:443

The Problem

Encountering SSL connection errors can halt your progress, particularly when trying to install packages using Homebrew on macOS. One error you might run into is: SSL_ERROR_SYSCALL in connection to raw.githubusercontent.com:443. This guide will provide detailed fixes to get Homebrew working flawlessly again.

Causes:

• Network issues that disrupt communication between your computer and GitHub’s servers.
• An outdated or misconfigured SSL/TLS library on your system.
• A misconfigured git client that is unable to negotiate an SSL handshake.
• Corporate firewalls or proxy settings that block access to GitHub’s servers.

Solution 1: Check Internet Connectivity

Basic network troubleshooting can ensure your internet connection isn’t the root cause. Verify that your connection is stable and other services aren’t experiencing issues.

• Verify your network connection.
• Attempt to access other websites and services.
• If using Wi-Fi, try switching to a wired connection to test.
• Reset your router or modem if necessary.

Steps:

1. Open a web browser and try visiting different websites.
2. Run a speed test to check your connection’s bandwidth and latency.
3. If issues persist, reboot your router and modem.

Notes: Often, these issues can be resolved by simple network checks and do not require any code changes, thus code example is not applicable. If this doesn’t solve the issue, proceed to more specific solutions.

Solution 2: Update Homebrew and Git

Updating your software can resolve compatibility issues. This includes both Homebrew and git, as well as the necessary libraries.

Steps:

1. Open the Terminal application.
2. Run brew update-reset to reset and update Homebrew.
3. Update git by running brew upgrade git.

Example:

$ brew update-reset
$ brew upgrade git

Output:

Updated Homebrew from [old version] to [new version].
Updated git from [old version] to [new version].

Notes: Updating software may not resolve underlying network issues, but will ensure you are running the latest version of Homebrew and git, potentially avoiding known bugs or compatibility issues.

Solution 3: Configure Git to Use HTTPS Instead of SSH

Some networks block SSH connections, which can be addressed by switching git to use HTTPS. This often bypasses corporate firewalls or proxy settings.

Steps:

1. Open the Terminal application.
2. Run git config --global url."https://".insteadOf git:// to configure git to use HTTPS.

Example:

$ git config --global url."https://".insteadOf git://

Output: This command does not generate output; it changes configuration settings.

Notes: Using HTTPS instead of SSH may be slower due to the HTTPS overhead. However, it often resolves connection issues related to SSL configuration or network blocks.

Solution 4: Disable SSL Verification (Not Recommended)

Disabling SSL verification is generally not recommended as it can make your connections vulnerable to man-in-the-middle attacks. However, as a temporary fix, it may help diagnose the issue or bypass certain network blocks.

Steps:

1. Open the Terminal application.
2. Run git config --global http.sslVerify false to disable SSL verification.

Example:

$ git config --global http.sslVerify false

Output: This command does not generate output; it changes configuration settings.

Notes: Use this method as a last resort and only temporarily. This renders your connection insecure, and you should revert the settings as soon as you find a secure solution to the problem.

Implementing these solutions usually resolves the SSL_ERROR_SYSCALL error. If you continue to experience problems, consider seeking additional assistance, potentially from your corporate IT department if you’re on a managed network, or reaching out to Homebrew’s community support.