Description:

/usr/lib/libnss_myhostname.so.2 exists in filesystem
/usr/lib/libnss_mymachines.so.2 exists in filesystem
/usr/lib/libnss_resolve.so.2 exists in filesystem

All 3 files are already in the systemd package and thus cause conflicts

Additional info:

yaourt -Syu --ignore mkvtoolnix-cli
:: Synchronizing package databases...
kde-unstable is up to date
testing is up to date
core is up to date
extra is up to date
community-testing is up to date
community is up to date


==> Package upgrade only (new release):
testing/libsystemd 226-1 1 -> 2
testing/systemd 226-1 1 -> 2

==> Continue upgrade ? [Y/n]
==> [V]iew package detail [M]anually select packages
==> --------------------------------------------------
==> y
:: Starting full system upgrade...
warning: mkvtoolnix-cli: ignoring package upgrade (8.3.0-1 => 8.4.0-1)
resolving dependencies...
looking for conflicting packages...

Package (2) Old Version New Version Net Change

testing/libsystemd 226-1 226-2 0.58 MiB
testing/systemd 226-1 226-2 0.00 MiB

Total Installed Size: 28.70 MiB
Net Upgrade Size: 0.58 MiB

:: Proceed with installation? [Y/n] y
(2/2) checking keys in keyring [---------------------------------------------------------------] 100%
(2/2) checking package integrity [---------------------------------------------------------------] 100%
(2/2) loading package files [---------------------------------------------------------------] 100%
(2/2) checking for file conflicts [---------------------------------------------------------------] 100%
error: failed to commit transaction (conflicting files)
/usr/lib/libnss_myhostname.so.2 exists in both 'libsystemd' and 'systemd'
/usr/lib/libnss_mymachines.so.2 exists in both 'libsystemd' and 'systemd'
/usr/lib/libnss_resolve.so.2 exists in both 'libsystemd' and 'systemd'
Errors occurred, no packages were upgraded.

Steps to reproduce:

attempt upgrade from libsystemd 226-1 to 226-2