Emerge config file needs updating
Generally, such migrations are not mandatory, and systems can continue to use the old profile - just update the packages as explained in the Gentoo Handbook.
However, Gentoo strongly recommends updating the profile if it becomes deprecated.
The files in the parent directories are part of the profile as well (and are therefore shared by different subprofiles). Profiles obsoleted by new ones are kept in is put in the profile directory.
The content of this file is the name of the profile that should be "upgraded to"; Portage uses this information to automatically warn administrators when they should update to a new profile.
Please read the UTF-8 article to learn how to create the proper locale.
Alternatively, if setting a locale is not preferred, then users need to specify .
To view the list of supported profiles, call Some systems are too old to just switch the profile.
Newer profiles might need more recent Portage versions or other software that cannot be installed anymore because the package definitions (ebuilds) for those older software versions are not available anymore.
From the beginning, Gentoo was designed around the concept of fast, incremental updates.To upgrade such systems, a recent stage3 can be used to update the system.Instructions for that are given in the Updating old systems section. For this to work, a Unicode locale for the system must be created.If this is the case, the system should first receive older Portage tree snapshots and upgrade at least Portage (but preferably all packages in the system set), gradually increasing the Portage tree snapshot date until it is recent enough to follow the profile switching instructions again: Older snapshots are often still available on some mirrors on the Internet or on specific locations dedicated for this purpose.It is recommended to verify the integrity of those files to make sure they are not tampered with: Although the release signing keys might be expired, the signature should still be OK. The upgrade path might need intermediate versions of software (such as portage) that does not exist any more, requiring to update the portage tree in steps (for instance incremental tree updates with steps of 3 to 4 months).