What the problem is

To put it in short this is what give me the head ache:

--> Finished Dependency Resolution
Error: Package: policycoreutils-2.5-11.el7_3.x86_64 (base)
           Requires: libsepol.so.1(LIBSEPOL_1.0)(64bit)
Error: Package: libsemanage-2.5-5.1.el7_3.x86_64 (base)
           Requires: libsepol.so.1(LIBSEPOL_1.0)(64bit)
Error: Package: 1:NetworkManager-tui-1.4.0-14.el7_3.x86_64 (base)
           Requires: libjansson.so.4()(64bit)
Error: Package: libsemanage-2.5-5.1.el7_3.x86_64 (base)
           Requires: libsepol.so.1(LIBSEPOL_1.1)(64bit)
Error: Package: 7:lvm2-2.02.166-1.el7_3.2.x86_64 (base)
           Requires: device-mapper-persistent-data >= 0.6.3-1
           Installed: device-mapper-persistent-data-0.6.2-1.el7_2.x86_64 (@base)
               device-mapper-persistent-data = 0.6.2-1.el7_2
Error: Package: policycoreutils-2.5-11.el7_3.x86_64 (base)
           Requires: libselinux-utils >= 2.5-6
           Installed: libselinux-utils-2.2.2-6.el7.x86_64 (@anaconda)
               libselinux-utils = 2.2.2-6.el7
Error: Package: 1:NetworkManager-libnm-1.4.0-14.el7_3.x86_64 (base)
           Requires: libjansson.so.4()(64bit)
Error: Package: 1:NetworkManager-1.4.0-14.el7_3.x86_64 (base)
           Requires: libjansson.so.4()(64bit)
Error: Package: kernel-3.10.0-514.6.1.el7.x86_64 (base)
           Requires: linux-firmware >= 20160830-49
           Installed: linux-firmware-20150904-43.git6ebf5d5.el7.noarch (@anaconda)
               linux-firmware = 20150904-43.git6ebf5d5.el7
Error: Package: policycoreutils-2.5-11.el7_3.x86_64 (base)
           Requires: libsepol >= 2.5-6
           Installed: libsepol-2.1.9-3.el7.x86_64 (@anaconda)
               libsepol = 2.1.9-3.el7
Error: Package: policycoreutils-2.5-11.el7_3.x86_64 (base)
           Requires: libsepol.so.1(LIBSEPOL_1.1)(64bit)
 You could try using --skip-broken to work around the problem
 You could try running: rpm -Va --nofiles --nodigest  

System information

The server runs CentOS 7. It has no extra repositories and uses only packages from the core CentOS 7 repos. There have been installed no software that is not provided by yum by default.

What I tried and what I found out

I have attempted a lot of things already, so I'll try to rule those out:

Cleaning yum

yum clean all basically.

Wiping the yum cache directory

rm -rf /var/cache/yum and rebuilding with yum makecache

Checking repository

I have tried several repositories and with all of them I did check that the update files are actually there. I even tried downloading some of the RPM's from the repo and updating them by hand, that works out just fine. But obviously I want yum to do this for me.

Checking repository configs

The files under /etc/yum.repos.d seem fine and match another server entirely, that works just perfect.

Checking the repolist

yum repolist - and here's a finding! See:

# yum repolist
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
repo id                             repo name                             status
base/7/x86_64                       CentOS-7 - Base                       807
extras/7/x86_64                     CentOS-7 - Extras                     807
updates/7/x86_64                    CentOS-7 - Updates                    807
repolist: 2,421 

Notice that there are only 807 packages in each. On my other servers there are way, way more available packages.

Checking the yum sqlite database

I tried downloading the primary_db.sqlite from the server to examine it with a SQLite editor. And there is in fact only 807 records in the packages table.

Obviously that has been cleared a ton of times, so it's not an old left over.

... And this is where you guys come in. I'm out of good ideas, but to me it seems to be narrowed down to the number 807. Why are there only 807 packages? I have, of course, googled like a maniac but I can't find anything like this.

I found another thread on here with someone who seems to have the same problem, but didn't give much info: Dependency conflict when updating Yum in CentOS 7

Updates

Comment 1

yum.conf

[main]
cachedir=/var/cache/yum/$basearch/$releasever
keepcache=0
debuglevel=2
logfile=/var/log/yum.log
exactarch=1
obsoletes=1
gpgcheck=1
plugins=1
installonly_limit=5
bugtracker_url=http://bugs.centos.org/set_project.php?project_id=23&ref=http://bugs.centos.org/bug_report_page.php?category=yum
distroverpkg=centos-release


#  This is the default, if you make this bigger yum won't see if the metadata
# is newer on the remote and so you'll "gain" the bandwidth of not having to
# download the new metadata and "pay" for it by yum not having correct
# information.
#  It is esp. important, to have correct metadata, for distributions like
# Fedora which don't keep old packages around. If you don't like this checking
# interupting your command line usage, it's much better to have something
# manually check the metadata once an hour (yum-updatesd will do this).
# metadata_expire=90m

# PUT YOUR REPOS HERE OR IN separate files named file.repo
# in /etc/yum.repos.d 

All yum.repos.d files http://pastebin.centos.org/65881/