Installation
Cylc 8 and its core software dependencies can be installed quickly from Conda Forge, into a conda environment; or from PyPI, into a Python 3 virtual environment.
Quick Installation
Cylc runs on Unix-like systems including Linux and Mac OS.
Via Conda (recommended)
Note
We recommend using the fast Mamba environment solver to install Cylc. Mamba can be used as a drop-in replacement for the conda command, or as a conda command plugin. The classic conda environment solver may be too slow for a complex package like Cylc.
$ conda install -c conda-forge cylc-flow
# Install the browser-GUI (optional)
$ conda install -c conda-forge cylc-uiserver
# Install Rose support (optional)
$ conda install -c conda-forge cylc-rose metomi-rose
Via Pip (+npm)
Note
Requires Python 3.7 - 3.9
Important
We recommend installing Cylc versions into virtual environments. This avoids software dependency conflicts and allows multiple Cylc versions to be installed on your system.
Without virtual environments, users can inadvertently break Cylc (or other
Python programs) by pip
-installing conflicting package versions to
$HOME/.local
, which takes precedence over central library locations.
$ pip install cylc-flow
# Install the browser-GUI (optional)
# (requires nodejs & npm)
$ pip install cylc-uiserver
# Install Rose support (optional)
$ pip install cylc-rose metomi-rose
There are also certain optional extra requirements which you may choose to install:
# Support for running the tutorial workflows
$ pip install 'cylc-flow[tutorial]'
# The GUI with multi-user (hub) support
$ pip install 'cylc-uiserver[hub]'
$ npm install configurable-http-proxy
You might also want to configure:
Non-Python Requirements
These dependencies are not installed by Conda or pip:
bash
GNU coreutils
ssh
rsync
mail
(optional - for automated email functionality)
These dependencies are installed by Conda but not by pip:
Graphviz (optional - used by
cylc graph
for displaying workflow graphs)configurable-http-proxy (optional - for multi-user setups; can also be installed using npm)
Installing On Mac OS
Cylc requires some extra packages to function on Mac OS. We recommend installing them using the Homebrew package manager:
$ brew install bash coreutils gnu-sed
You will need to prepend the coreutils
and gnu-sed
installations to
your $PATH
, follow the instructions in the brew install
output.
Note
atrun (the at
command) does not run out-of-the-box on Mac OS
for security reasons and must be manually enabled.
Note
Newer version of Mac OS set zsh
as the default shell (as opposed to
bash
). You do not need to change this but be aware that Cylc uses
bash
(for job scripts) which has a subtly different syntax.
Warning
For Mac OS Versions 10.15.0 (Catalina) and higher SSH is disabled by default. The ability to SSH into your Mac OS box may be required for certain Cylc installations.
See the Apple support page for instructions on enabling SSH.
Advanced Installation
For distributed and multi-user installation we recommend using Conda and installing Cylc components only where required.
Tip
For examples of Conda environments and installation options see Conda Environments for examples and details.
The Cylc Components
Cylc is split into a number of components providing different functionality:
- Cylc Flow
Provides the scheduler “kernel” of Cylc along with the command line interface.
- Cylc UI Server
Provides the “Cylc Hub” and the browser-based “Cylc GUI”.
- Cylc Rose
Provides support for Rose suite configurations in Cylc workflows.
Installation Types
Cylc install locations may fall into the following “roles”:
- User Machines
Where users write workflows and interact with the command line.
- Cylc Servers
Where Cylc schedulers run to manage workflows.
- Job Hosts
Where jobs run, e.g. supercomputers or clusters
Note
These roles may overlap. For example, Cylc servers can also be job hosts.
Recommended Installation
Managing Environments
For Cylc to run, the correct environment must be activated. Cylc can not do this automatically. You may need to have multiple Cylc versions available too.
We recommend using a wrapper script named cylc
to activate the correct
environment before calling the environment’s cylc
command.
Cylc comes with a wrapper that can be adapted to point at your Cylc
environments. Extract it to a directory in your $PATH
like this:
cylc get-resources cylc /path/to/cylc # should be in $PATH
chmod +x /path/to/cylc
You may need to modify this file for your local installation e.g:
- CYLC_HOME_ROOT="${CYLC_HOME_ROOT:-/opt}"
+ CYLC_HOME_ROOT="${CYLC_HOME_ROOT:-/path/to}"
Note
Developers can set $CYLC_HOME_ROOT_ALT
to point
to their development environments. For example:
CYLC_HOME_ROOT_ALT=${HOME}/.conda/envs
You may wish to use the same approach for the isodatetime
command, and, if using
Rose for the rose
and rosie
commands.
To do so create a symbolic link to the wrapper, for each of these commands:
cd /path/to # Using the path where you installed the wrapper script
ln -s cylc rose
ln -s cylc rosie
ln -s cylc isodatetime
Configuration
Cylc uses sane and safe defaults and is suitable for use “out of the box”, if all you need to do is run jobs locally in the background. However, many things may need to be configured, e.g:
Platform Configuration (jobs hosts, runners, etc)
Cylc Flow
Cylc Flow is configured by the global.cylc
file which supports
configuration of the system on both a site and user basis.
Note
Prior to Cylc 8, global.cylc
was named global.rc
, but that name is
no longer supported.
The global.cylc file should be available on user machines (where users interact with Cylc on the command line) and on cylc servers (where Cylc schedulers run). It is not required to be available on job hosts.
More information about supported configuration items and defaults can be found: Global Configuration.
Cylc UI Server
The Cylc UI Server can be configured on a site and user basis. Guidance for configuration file storage, configuration variables and defaults can be found: UI Server Configuration.
Bash Profile
Cylc job scripts are bash scripts, which is good for
manipulating files and processes, They invoke bash -l
to allow environment
configuration in login scripts.
Warning
Sites and users should ensure their bash login scripts configure the environment correctly for Cylc and do not write anything to stdout.
Shell Auto-Completion
Cylc provides auto-completion for the Bash shell which can save you typing:
Cylc commands
Workflow IDs
Cycle points
Task names
To extract the auto-completion file run the following command:
cylc get-resources cylc-completion.bash <path-to-copy-file>
Then follow the comments in the file to install it.
Text Editors
There is support for the .cylc
file format in various text editors.
See Syntax Highlighting For Workflow Configuration for more details.