Mirroring channels#

The conda configuration system has several keys that can be used to set up a mirrored context.

The default setup#

By default, conda can serve packages from two main locations:

  • repo.anaconda.com: this is where defaults points to by default. The default value has been marked for pending deprecation as of conda 24.9.0, but it is still the default for older versions. In conda 25.3.0, this default will be removed.

    This base location is hardcoded in the default value of default_channels:

    • https://repo.anaconda.com/pkgs/main

    • https://repo.anaconda.com/pkgs/r

    • https://repo.anaconda.com/pkgs/msys2

  • conda.anaconda.org: this is where conda clients look up community channels like conda-forge or bioconda. This base location can be configured via channel_alias.

So, when it comes to mirroring these channels, you have to account for those two locations.

Mirror defaults#

Use default_channels to overwrite the default configuration. For example:

default_channels:
    - https://my-mirror.com/pkgs/main
    - https://my-mirror.com/pkgs/r
    - https://my-mirror.com/pkgs/msys2

Mirror all community channels#

Redefine channel_alias to point to your mirror. For example:

channel_alias: https://my-mirror.com

This will make conda look for all community channels at https://my-mirror.com/conda-forge, https://my-mirror.com/bioconda, etc.

Mirror only some community channels#

If you want to mirror only some community channels, you must use custom_channels. This takes precedence over channel_alias. For example:

custom_channels:
    conda-forge: https://my-mirror.com/conda-forge

With this configuration, conda-forge will be looked up at https://my-mirror.com/conda-forge. All other community channels will be looked up at https://conda.anaconda.org.

Note

Feel free to explore all the available options in Configuration.