Cylc 8 global.rc configuration location

Hi all,

Could anyone tell me where the global.rc file is supposed to be located for cylc 8? I’m trying to set the cylc work directory to point to our scratch disk, instead of running out of $HOME/cylc-run.

Previous versions were located in HOME/.cylc/(cylc-version)/global.rc. I tried to do the same with cylc-8, but it doesn’t seem to see it. I installed cylc-8 through conda.




Thanks for testing Cylc8 alpha.

The work is currently at an early phase, we haven’t yet decided on where configurations are going to be stored for the different Cylc components and how that will work with multiple environments etc. For reference the open issue is here:

In the mean time Cylc8 alpha is currently looking for global configuration files in the following locations:

  • /etc/cylc/flow/<version>/flow.rc
  • $HOME/.cylc/flow/<version>/flow.rc

The flow.rc is pretty much the same as the old global.rc with a few deprecations and tweaks (more to come).

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Thanks a lot Oliver–this worked.

You are welcome, but using Cylc 8 is more of a necessity for us since we need to move off of python 2 as fast as possible.

By the way, is there any alpha documentation available for cylc 8?

Hi Dan,

We have a Cylc 8 version of the User Guide, which we will make available with the upcoming 8.0a2 alpha release. It does document some changes and improvements to the workflow configuration syntax, but a) there are actually not many of those as we are trying to maintain backward compatibility in that respect; and b) it does not yet document the Cylc 8 architecture, how to use it, or any of the implications thereof - which is where the really big Cylc 8 changes are.

We definitely do not recommend using Cylc 8 for anything important yet, it is still undergoing heavy development and many important issues have not been addressed at this stage. Hopefully you have seen the warnings here:

However, if you want (or need) to keep experimenting, feel free to keep asking questions here.

Note that cylc-8.0a1 was a very early release. We intend to release cylc-8.0a2 by end of January - or soon thereafter - with some major improvements. Or you can start at the bleeding edge, with git clones of all the Cylc 8 components.

The Cylc 8 User Guide, BTW, is maintained in its own repository, here:



Thanks for the documentation link–I figured out what the issue was. I was originally thinking that my errors might have been related to some deprecated items not being upgraded properly, but as it turns out, one of my Python functions that was written to handle some quirks of our PBS system was relying on cylc.batch_sys_handlers, which no longer exists. Apparently the issue that we originally had is no longer an issue for cylc 8 (hooray)!

We’ve actually been running cylc 8 continuously since mid-December to schedule background jobs, and I’ve just set it up on our HPC system which is using a PBS queue. The jobs seem to be completing ok, so I think things are fully functional.

We are a research institution, so we won’t be running anything operational with cylc 8 yet.


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Wow, well done - that’s brilliant! :grin:

Yes I should have mentioned that the back-end Cylc 8 workflow service and CLI (cylc-flow) is fully functional at Python 3 already (with some provisos, e.g. authentication needs work and authorization isn’t done at all yet). It’s mainly the new UI and associated components (Hub and UI Server) that are still evolving fast.

In Cylc 8 use (e.g.)

from cylc.flow.batch_sys_handlers.pbs import PBSHandler