Total 99 kB/s | 143 MB 24:36
Delta RPMs reduced 902.8 MB of updates to 880.0 MB (2.1% saved)
Running transaction check
Transaction check succeeded.
Running transaction test
The downloaded packages were saved in cache until the next successful transaction.
You can remove cached packages by executing 'dnf clean packages'.
Error: Transaction check error:
file /usr/share/doc/glibc/NEWS from install of glibc-2.25-12.fc26.i686 conflicts with file from package glibc-2.25-7.fc26.x86_64
file /usr/share/man/man1/xmlwf.1.gz from install of expat-2.2.4-1.fc26.i686 conflicts with file from package expat-2.2.1-1.fc26.x86_64
file /usr/share/libdrm/amdgpu.ids from install of libdrm-2.4.88-1.fc26.i686 conflicts with file from package libdrm-2.4.82-1.fc26.x86_64
file /usr/share/doc/fontconfig/README from install of fontconfig-2.12.6-4.fc26.i686 conflicts with file from package fontconfig-2.12.1-4.fc26.x86_64
file /usr/share/fontconfig/conf.avail/30-metric-aliases.conf from install of fontconfig-2.12.6-4.fc26.i686 conflicts with file from package fontconfig-2.12.1-4.fc26.x86_64
file /usr/share/fontconfig/conf.avail/30-urw-aliases.conf from install of fontconfig-2.12.6-4.fc26.i686 conflicts with file from package fontconfig-2.12.1-4.fc26.x86_64
file /usr/share/fontconfig/conf.avail/45-latin.conf from install of fontconfig-2.12.6-4.fc26.i686 conflicts with file from package fontconfig-2.12.1-4.fc26.x86_64
file /usr/share/fontconfig/conf.avail/60-latin.conf from install of fontconfig-2.12.6-4.fc26.i686 conflicts with file from package fontconfig-2.12.1-4.fc26.x86_64
file /usr/share/fontconfig/conf.avail/65-nonlatin.conf from install of fontconfig-2.12.6-4.fc26.i686 conflicts with file from package fontconfig-2.12.1-4.fc26.x86_64
file /usr/bin/fc-cache from install of fontconfig-2.12.6-4.fc26.i686 conflicts with file from package fontconfig-2.12.1-4.fc26.x86_64
file /usr/share/doc/fontconfig/fontconfig-user.html from install of fontconfig-2.12.6-4.fc26.i686 conflicts with file from package fontconfig-2.12.1-4.fc26.x86_64
file /usr/share/doc/fontconfig/fontconfig-user.txt from install of fontconfig-2.12.6-4.fc26.i686 conflicts with file from package fontconfig-2.12.1-4.fc26.x86_64
file /usr/share/man/man5/fonts-conf.5.gz from install of fontconfig-2.12.6-4.fc26.i686 conflicts with file from package fontconfig-2.12.1-4.fc26.x86_64
file /usr/share/doc/libgcrypt/AUTHORS from install of libgcrypt-1.7.9-1.fc26.i686 conflicts with file from package libgcrypt-1.7.8-1.fc26.x86_64
file /usr/share/doc/libgcrypt/NEWS from install of libgcrypt-1.7.9-1.fc26.i686 conflicts with file from package libgcrypt-1.7.8-1.fc26.x86_64
file /usr/share/doc/gstreamer1/NEWS from install of gstreamer1-1.12.3-1.fc26.i686 conflicts with file from package gstreamer1-1.12.2-1.fc26.x86_64
file /usr/share/doc/gstreamer1/README from install of gstreamer1-1.12.3-1.fc26.i686 conflicts with file from package gstreamer1-1.12.2-1.fc26.x86_64
file /usr/share/doc/gstreamer1/RELEASE from install of gstreamer1-1.12.3-1.fc26.i686 conflicts with file from package gstreamer1-1.12.2-1 ...
Somehow dnf is trying to install newer versions of 32-bit libraries than the 64-bit ones that are already installed and isn't updating the 64-bit ones which is very strange. Usually it's the other way around. It would be helpful to see the list of packages that dnf is trying to install. Try adding --refresh to the dnf command line and if that still doesn't help, try again tomorrow.
Update:
I just noticed the title of this question. This doesn't look like you're upgrading to F27, it looks like just a normal update. What is the dnf command you used?
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