PostgreSQL 16 Install Error On Rocky Linux 9: OpenSSL Mismatch

by Alex Johnson 63 views

Facing issues with PostgreSQL 16 on Rocky Linux 9? You're not alone. Many users have encountered problems when trying to install or update postgresql16-contrib-16.11-1pgdg.rhel9.x86_64 on Rocky Linux 9 due to an OpenSSL version mismatch. This article delves into the root cause of the issue, its implications, and potential solutions to help you get your PostgreSQL 16 instance up and running smoothly. The error typically arises because the package is built against a newer version of OpenSSL than what's available in the standard Rocky Linux 9 repositories.

Understanding the Problem: OpenSSL and PostgreSQL Compatibility

The core of the problem lies in the compatibility between PostgreSQL packages and the OpenSSL libraries. Specifically, the postgresql16-contrib package, provided by the PostgreSQL Global Development Group (PGDG) repositories, requires a specific OpenSSL version that is not available in the default Rocky Linux 9 installation. This mismatch prevents the package from installing or updating, leading to a frustrating error message. Let's break down the error message to understand it better:

Error:
Problem 1: cannot install the best update candidate for package postgresql16-contrib-16.10-1PGDG.rhel9.x86_64
 - nothing provides libcrypto.so.3(OPENSSL_3.4.0)(64bit) needed by postgresql16-contrib-16.11-1PGDG.rhel9.x86_64 from pgdg16

This part of the error tells us that postgresql16-contrib-16.11-1pgdg.rhel9.x86_64 needs libcrypto.so.3 with OPENSSL_3.4.0. However, this specific version isn't present in the Rocky Linux 9 system. This is a common issue when software packages are built against newer library versions than those available in your operating system's package repositories. The PGDG repositories provide pre-built packages for various Linux distributions, but these packages are built in an environment with specific dependencies. When those dependencies (like OpenSSL) are newer than what's in your system, you get an incompatibility.

Problem 2: problem with installed package postgresql16-contrib-16.10-1PGDG.rhel9.x86_64
 - package postgresql16-contrib-16.10-1PGDG.rhel9.x86_64 from @System requires postgresql16(x86-64) = 16.10-1PGDG.rhel9, but none of the providers can be installed
 - package postgresql16-contrib-16.10-1PGDG.rhel9.x86_64 from pgdg16 requires postgresql16(x86-64) = 16.10-1PGDG.rhel9, but none of the providers can be installed
 - cannot install both postgresql16-16.11-1PGDG.rhel9.x86_64 from pgdg16 and postgresql16-16.10-1PGDG.rhel9.x86_64 from @System
 - cannot install both postgresql16-16.11-1PGDG.rhel9.x86_64 from pgdg16 and postgresql16-16.10-1PGDG.rhel9.x86_64 from pgdg16
 - cannot install the best update candidate for package postgresql16-16.10-1PGDG.rhel9.x86_64
 - nothing provides libcrypto.so.3(OPENSSL_3.4.0)(64bit) needed by postgresql16-contrib-16.11-1PGDG.rhel9.x86_64 from pgdg16

The remaining parts of the error message highlight conflicts between different versions of PostgreSQL packages and further emphasize the missing OpenSSL dependency. These conflicts occur because the package manager (like dnf in this case) cannot resolve the dependencies due to the OpenSSL incompatibility.

Why This Happens and Who It Affects

This issue typically arises because the PGDG repositories build their packages in an environment that may be slightly ahead in terms of library versions (like OpenSSL) compared to the stable releases of operating systems such as Rocky Linux 9. The original reporter in the provided text correctly suspects that the build environment for the PGDG RPMs might be using a newer version of OpenSSL. This means that the packages are built with a dependency on a more recent OpenSSL version than what's available in the default Rocky Linux 9 repositories. Consequently, users of RHEL 9, Rocky Linux 9, and AlmaLinux 9 are most likely to encounter this problem. There's also a possibility that users of Oracle Linux 9 may face a similar situation.

Potential Solutions and Workarounds

While the ideal solution would involve the PGDG repositories providing packages built against the OpenSSL version available in Rocky Linux 9, there are several workarounds you can try:

1. Check for Updated Packages:

  • Verify Repository Synchronization: Ensure that your system's package manager has correctly synchronized with the PGDG repositories. Run sudo dnf clean all followed by sudo dnf update to refresh the package metadata and check if newer packages that resolve the dependency issue are available. Sometimes, the issue is resolved by simply waiting for the package maintainers to update the repository.
  • Review Available Versions: Examine the available versions of the postgresql16-contrib package in the PGDG repository to see if there's a version compatible with your OpenSSL installation using sudo dnf list postgresql16-contrib --showduplicates. If an older version that doesn't require the newer OpenSSL is available, you might consider installing that.

2. Downgrading or Using an Older Version (If Possible):

  • Downgrade PostgreSQL: If the OpenSSL mismatch prevents installation, consider temporarily downgrading your PostgreSQL installation to a version compatible with your current OpenSSL version. This might involve removing the newer PostgreSQL packages and installing an older version that doesn't depend on the problematic OpenSSL version.
  • Install Specific Older Packages: If a specific older version of postgresql16-contrib is known to work, you can try installing it directly using a command like sudo dnf install postgresql16-contrib-16.x.x-PGDG.rhel9.x86_64, replacing 16.x.x with the appropriate version number. However, this is not always recommended due to potential compatibility issues.

3. Using a Different Repository or Build Environment (Advanced):

  • Alternative Repositories: Explore if there are alternative PostgreSQL repositories that provide packages built against the OpenSSL version in Rocky Linux 9. However, be cautious when using third-party repositories, as they may not be as well-maintained or thoroughly tested as the official PGDG repository.
  • Building from Source: As a last resort, you could consider building the postgresql16-contrib package from source. This allows you to compile it against the OpenSSL version installed on your system. This approach is more complex and requires a good understanding of the build process and dependencies.

4. Using --skip-broken or --nobest (Use with Caution):

  • --skip-broken: The error message suggests using --skip-broken. This tells dnf to skip any packages that have broken dependencies. This can potentially allow you to install other packages, but it could leave your system in an inconsistent state, where some packages are installed but others that depend on them are not. Use this option cautiously, and only if you fully understand the implications. It may be a temporary fix to allow other updates but it won't resolve the core issue.
  • --nobest: The --nobest option tells dnf to not only consider the best candidate for installation. This might help if a less recent version of the package is available and compatible with your system's OpenSSL version. It may help you install a functional package at the expense of it not being the absolute latest version. Again, consider the compatibility and potential security implications of not being on the newest version.

5. Contacting PGDG or Rocky Linux Support:

  • Report the Issue: If the problem persists, report the issue to the PGDG maintainers or the Rocky Linux community. This helps them become aware of the problem and work towards a permanent solution. Provide detailed information about your system configuration and the error messages you are encountering.
  • Community Forums: Seek help from the Rocky Linux community forums or other relevant online communities. Other users may have encountered the same problem and found a solution or workaround.

Detailed Steps for a Potential Solution (Using dnf)

Note: Before proceeding, it's highly recommended to back up your system or at least the PostgreSQL data directory to prevent data loss. These steps are a general guide, and specific commands might need adjustment based on your environment. Always carefully review what you're doing before executing any commands. Also, these are not guaranteed to work, and using the wrong commands can cause damage.

  1. Update the System:

    sudo dnf update -y

    This ensures your system is up-to-date, which sometimes resolves dependency issues.

  2. Clean DNF Cache:

    sudo dnf clean all

    This clears the DNF cache to get a fresh start with package information.

  3. Check Available PostgreSQL Packages:

    sudo dnf list postgresql16-contrib --showduplicates

    This lists all available versions of the postgresql16-contrib package from the enabled repositories, helping you identify compatible versions.

  4. Attempt Installation (with Caution):

    If you've identified a specific version from step 3 that might be compatible, attempt to install it. If not, try installing with the skip-broken flag.

    # Example:  Replace 16.10 with a compatible version, if available
sudo dnf install postgresql16-contrib-16.10-1PGDG.rhel9.x86_64
# or try the skip broken command.
sudo dnf install --skip-broken postgresql16-contrib

  5. Check for Missing Dependencies:

    If the installation fails, examine the output for more details about missing dependencies. This will provide hints regarding the packages you need to install or update manually. Repeat steps to ensure all dependencies are met.

  6. Resolve Conflicts (If Any):

    If there are package conflicts, you'll need to resolve them. This might involve removing conflicting packages. Be extremely careful when removing packages, as you could break your system. Make sure you understand the implications before removing packages.

  7. Final Update and Verification:

    sudo dnf update -y
sudo dnf install postgresql16-contrib

    Run these commands to ensure that the system is fully up to date and that all the dependent packages are properly installed. Then check PostgreSQL's service status.

    sudo systemctl status postgresql-16

  8. Restart PostgreSQL Service (If Necessary):

    sudo systemctl restart postgresql-16

    After installing or updating the PostgreSQL server and contrib packages, restart the service to apply the changes.

Long-Term Solutions and Prevention

While the workarounds mentioned above can help in the short term, the best solution involves addressing the root cause. Here's what you can consider for long-term solutions:

  • Waiting for Package Updates: The simplest approach might be to wait for the PGDG repositories to release updated packages that are compatible with the OpenSSL version in Rocky Linux 9. This is often the most straightforward solution, as it doesn't require any manual intervention.
  • Package Maintainer Communication: Consider contacting the PGDG maintainers to report the issue. This informs them about the problem and helps them prioritize the development of compatible packages. Providing them with details about the Rocky Linux 9 environment and the OpenSSL version will assist them in addressing the issue effectively.
  • Custom Package Builds: For advanced users, building custom packages from source can provide the most control. This involves downloading the source code, making necessary modifications (if required), and compiling the packages with the desired OpenSSL version. Building from source is complex and time-consuming, but can provide the most flexibility.
  • Monitoring and Maintenance: Regularly monitor the PGDG repositories and the Rocky Linux security updates for package updates. Keep your system updated to the latest security and stability updates.

Conclusion

The OpenSSL version mismatch when installing postgresql16-contrib-16.11-1pgdg.rhel9.x86_64 on Rocky Linux 9 is a common issue. By understanding the root cause, trying out workarounds, and considering long-term solutions, you can successfully install and update your PostgreSQL 16 instance. Remember to prioritize your data and consider using the community for help and support. The issue is likely to be resolved by waiting for the package maintainers to update their packages or by updating to a newer OpenSSL version.

For more detailed information and troubleshooting guides, consider visiting these sites:

  • PostgreSQL Official Documentation: Explore the official PostgreSQL documentation for detailed information about PostgreSQL configurations and settings. PostgreSQL Documentation
  • Rocky Linux Official Documentation: Consult the official Rocky Linux documentation for up-to-date system information and troubleshooting tips. The documentation covers a wide range of system administration topics.
  • PGDG Repository: The official repository is the best location for the latest updates. Check for the most current updates on the PGDG project site.