Failed to install sys-apps/portage – Called pkg_preinst – portage._compat_upgrade.default_locations

Recently there was a problem with one compute node servers, which Gentoo (in fact, the chroot environment had not been updated for 3 years) could not emerge the new portage because it kept failing in the pkg_preinst with:

srv ~ # USE="-rsync-verify" emerge -va '=sys-apps/portage-2.3.76::gentoo'
>>> Installing (1 of 1) sys-apps/portage-2.3.76::gentoo
 * checking 1999 files for package collisions
1000 files checked ...
^[[B>>> Merging sys-apps/portage-2.3.76 to /
/usr/bin/python2.7: No module named _compat_upgrade
 * ERROR: sys-apps/portage-2.3.76::gentoo failed (preinst phase):
 *   (no error message)
 * Call stack:
 *, line 133:  Called pkg_preinst
 *   environment, line 3238:  Called die
 * The specific snippet of code:
 * If you need support, post the output of `emerge --info '=sys-apps/portage-2.3.76::gentoo'`,
 * the complete build log and the output of `emerge -pqv '=sys-apps/portage-2.3.76::gentoo'`.
 * The complete build log is located at '/var/tmp/portage/sys-apps/portage-2.3.76/temp/build.log'.
 * The ebuild environment file is located at '/var/tmp/portage/sys-apps/portage-2.3.76/temp/environment'.
 * Working directory: '/var/tmp/portage/._portage_reinstall_.RKkxLW/pym'
 * S: '/var/tmp/portage/sys-apps/portage-2.3.76/work/portage-2.3.76'
!!! FAILED preinst: 1

>>> Failed to install sys-apps/portage-2.3.76, Log file:

>>>  '/var/tmp/portage/sys-apps/portage-2.3.76/temp/build.log'

Note this is the installation phase, where everything from the build process passes smoothly, but it fails to install it with some vague error of a dying line with a couple of python and portage environments. The problem is the current portage does not support EAPI 6 and 7 and some packages were unable to be installed!

And we fixed the issue by just using the method described in our previous article – Fix your broken or old portage in Gentoo, fix the emerge command
Cloning a new portage software and using it to emerge (install) a newer (or reinstall the current) portage in the system to fix the system’s portage and the emerge command:

cd /root
git clone
/root/portage/bin/emerge --sync
eselect profile set default/linux/amd64/17.1
/root/portage/bin/emerge -v portage

Now the latest and stable Gentoo profile is 17.1, so we set it to be sure we use it (in future this may change).
Keep on reading!