Package installation problem: python 3.12 and dnf on RHEL8/RHEL9

[VadimJCA]

In a very basic setup, we fail to deploy a PostgreSQL 17 cluster from pigsty 3.7.0 because of
TASK [pgsql : install postgres packages] **************************************************************************************************************************************************************************************************** [ERROR]: Task failed: Module failed: Could not import the dnf python module using /usr/bin/python3.12 (3.12.11 (main, Aug 26 2025, 15:44:11) [GCC 8.5.0 20210514 (Red Hat 8.5.0-26)]). Please installpython3-dnfpackage or ensure you have specified the correct ansible_python_interpreter. (attempted ['/usr/libexec/platform-python', '/usr/bin/python3', '/usr/bin/python']) Origin: /opt/pigsty/roles/pgsql/tasks/install.yml:44:7

It looks like pigsty brought it's own python3.12 and uses it instead of whatever python was shipped with the OS. But we can't install python3-dnf to that python3.12 because that specific module can only work with system python, which is 3.6.8 (ant best 3.9 if we go with RHEL9).

I was under the imperssion that there is no need to tweak pigsty's playbooks and inventories other that main pigsty.yml to deploy a simple cluster. And since python3.12 seems to be required at least for the newer jmespath - a generic fallback to system python is not a solution either.

How should we navigate this?

[Vonng]

The issue is caused by recent changes in linux upstream packages. My guess is that installing it via python3.12 -m pip should resolve the problem.

Since EL10 already provides official support and EL8 doesn’t support io_uring, we’re planning to drop EL8 support in the next release. So the simplest solution—if it’s an option for you—is to switch to EL10 or EL9. (or debian / ubuntu)

[VadimJCA]

I'm confused. This /tmp/pkg.tgz - isn't it only for bootstrap script for pigsty itself? While I'm currently stuck with bin/node-add failing over broken URLs on the target host, where the client cluster should appear. Are you telling me bin/node-add will actually look for /tmp/pkg.tgz on target too?

[VadimJCA]

Just checked. It doesn't. That would be too good. So am I to assume you meant I shoud exploit bootstrap on target just to get the necessary packages installed and then run bin/node-add?

[Vonng]

https://doc.pgsty.com/install/offline/

[VadimJCA]

More specific it was https://doc.pgsty.com/install/offline/#offline-package
that helped. Wasn't clear that after offline installation of pigsty I just needed to set repo_enabled: true and node_repo_modules: local.
Thank you!

I switched to Rocky 9.7 everywhere now. So I'm fixing the title.