Peut-être est-ce lié au fait que je ne donne pas les droits administrateurs aux utilisateurs lors de l'installation.
Ci-dessous le contenu de /var/log/yum.log :
Sep 05 20:45:33 Erased: mediainfo-0.7.58-277.1.x86_64
Sep 05 20:45:34 Erased: mediainfo-gui-0.7.58-277.1.x86_64
Sep 05 20:45:34 Erased: libmediainfo0-0.7.58-267.1.x86_64
Sep 05 20:45:35 Erased: libzen0-0.4.27-172.1.x86_64
Sep 05 20:46:09 Installed: libzen-0.4.31-2.fc21.x86_64
Sep 05 20:46:09 Installed: tinyxml2-2.1.0-4.20140406git6ee53e7.fc21.x86_64
Sep 05 20:46:10 Installed: libmediainfo-0.7.76-1.fc21.x86_64
Sep 05 20:46:11 Installed: mediainfo-gui-0.7.76-1.fc21.x86_64
Sep 05 20:46:11 Installed: mediainfo-0.7.76-1.fc21.x86_64
Sep 05 20:46:37 Updated: bash-4.3.42-1.fc21.x86_64
Sep 05 20:46:38 Updated: 1:openssl-libs-1.0.1k-12.fc21.x86_64
Sep 05 20:46:38 Updated: 1:dbus-libs-1.8.20-1.fc21.x86_64
Sep 05 20:46:38 Updated: libselinux-2.3-10.fc21.x86_64
Sep 05 20:46:39 Updated: pango-1.36.8-6.fc21.x86_64
Sep 05 20:46:42 Updated: gtk3-3.14.15-1.fc21.x86_64
Sep 05 20:46:46 Updated: python-libs-2.7.8-11.fc21.x86_64
Sep 05 20:46:47 Updated: python-2.7.8-11.fc21.x86_64
Sep 05 20:46:47 Updated: gnutls-3.3.17-1.fc21.x86_64
Sep 05 20:46:48 Updated: elfutils-libelf-0.163-1.fc21.x86_64
Sep 05 20:46:48 Updated: libsss_idmap-1.12.5-3.fc21.x86_64
Sep 05 20:46:49 Updated: avahi-libs-0.6.31-32.fc21.x86_64
Sep 05 20:46:49 Updated: audit-libs-2.4.4-1.fc21.x86_64
Sep 05 20:46:50 Updated: glusterfs-libs-3.5.5-2.fc21.x86_64
Sep 05 20:46:50 Updated: libseccomp-2.2.3-0.fc21.x86_64
Sep 05 20:46:51 Updated: 1:dbus-1.8.20-1.fc21.x86_64
Sep 05 20:46:52 Updated: openssh-6.6.1p1-16.fc21.x86_64
Sep 05 20:46:53 Updated: glusterfs-3.5.5-2.fc21.x86_64
Sep 05 20:46:53 Updated: glusterfs-api-3.5.5-2.fc21.x86_64
Sep 05 20:46:53 Updated: avahi-glib-0.6.31-32.fc21.x86_64
Sep 05 20:46:55 Updated: ffmpeg-libs-2.4.11-1.fc21.x86_64
Sep 05 20:46:55 Updated: libselinux-python-2.3-10.fc21.x86_64
Sep 05 20:46:56 Updated: system-config-printer-libs-1.5.7-3.fc21.noarch
Sep 05 20:46:57 Updated: libidn-1.32-1.fc21.x86_64
Sep 05 20:47:39 Updated: selinux-policy-3.13.1-105.20.fc21.noarch
Sep 05 20:47:43 Installed: kernel-core-4.1.5-100.fc21.x86_64
Sep 05 20:47:43 Updated: libsss_nss_idmap-1.12.5-3.fc21.x86_64
Sep 05 20:47:44 Installed: polkit-libs-0.113-4.fc21.x86_64
Sep 05 20:47:44 Updated: 32:bind-license-9.9.6-10.P1.fc21.noarch
Sep 05 20:47:45 Updated: procps-ng-3.3.10-8.fc21.x86_64
Sep 05 20:47:46 Updated: flac-libs-1.3.1-5.fc21.x86_64
Sep 05 20:47:47 Updated: open-vm-tools-9.10.2-1.fc21.x86_64
Sep 05 20:47:47 Updated: 32:bind-libs-lite-9.9.6-10.P1.fc21.x86_64
Sep 05 20:47:48 Updated: 32:bind-libs-9.9.6-10.P1.fc21.x86_64
Sep 05 20:47:49 Updated: 32:bind-utils-9.9.6-10.P1.fc21.x86_64
Sep 05 20:47:50 Installed: polkit-0.113-4.fc21.x86_64
Sep 05 20:47:50 Updated: sssd-client-1.12.5-3.fc21.x86_64
Sep 05 20:47:57 Installed: kernel-modules-4.1.5-100.fc21.x86_64
Sep 05 20:47:58 Updated: python-slip-0.6.3-1.fc21.noarch
Sep 05 20:47:58 Updated: libavdevice-2.4.11-1.fc21.x86_64
Sep 05 20:47:58 Updated: 1:dbus-x11-1.8.20-1.fc21.x86_64
Sep 05 20:47:59 Updated: elfutils-libs-0.163-1.fc21.x86_64
Sep 05 20:48:04 Updated: wireshark-1.12.6-1.fc21.x86_64
Sep 05 20:48:04 Updated: gnutls-dane-3.3.17-1.fc21.x86_64
Sep 05 20:48:05 Updated: tkinter-2.7.8-11.fc21.x86_64
Sep 05 20:48:05 Installed: python-characteristic-14.3.0-1.fc21.noarch
Sep 05 20:48:05 Updated: python-sssdconfig-1.12.5-3.fc21.noarch
Sep 05 20:48:06 Installed: python-idna-2.0-1.fc21.noarch
Sep 05 20:48:06 Updated: python-pillow-2.6.2-2.fc21.x86_64
Sep 05 20:48:07 Installed: python-munch-2.0.2-2.fc21.noarch
Sep 05 20:48:07 Updated: python-fedora-0.5.5-2.fc21.noarch
Sep 05 20:48:08 Installed: python-pyasn1-modules-0.1.7-4.fc21.noarch
Sep 05 20:48:08 Installed: python-service-identity-14.0.0-1.fc21.noarch
Sep 05 20:48:09 Updated: libselinux-python3-2.3-10.fc21.x86_64
Sep 05 20:48:09 Updated: python3-slip-0.6.3-1.fc21.noarch
Sep 05 20:48:10 Updated: libuser-0.62-1.fc21.x86_64
Sep 05 20:48:10 Updated: libuser-python-0.62-1.fc21.x86_64
Sep 05 20:48:11 Updated: httpd-tools-2.4.16-1.fc21.x86_64
Sep 05 20:48:15 Installed: gnome-icon-theme-legacy-3.12.0-2.fc21.noarch
Sep 05 20:48:16 Updated: httpd-filesystem-2.4.16-1.fc21.noarch
Sep 05 20:48:16 Updated: gzip-1.6-8.fc21.x86_64
Sep 05 20:48:16 Updated: nss-sysinit-3.19.3-1.0.fc21.x86_64
Sep 05 20:48:17 Updated: nss-3.19.3-1.0.fc21.x86_64
Sep 05 20:48:18 Updated: sssd-krb5-common-1.12.5-3.fc21.x86_64
Sep 05 20:48:19 Updated: sssd-common-1.12.5-3.fc21.x86_64
Sep 05 20:48:19 Updated: sssd-common-pac-1.12.5-3.fc21.x86_64
Sep 05 20:48:20 Updated: 1:librados2-0.80.10-1.fc21.x86_64
Sep 05 20:48:21 Updated: 1:librbd1-0.80.10-1.fc21.x86_64
Sep 05 20:48:21 Updated: sssd-ad-1.12.5-3.fc21.x86_64
Sep 05 20:48:21 Updated: sssd-ldap-1.12.5-3.fc21.x86_64
Sep 05 20:48:22 Updated: sssd-krb5-1.12.5-3.fc21.x86_64
Sep 05 20:48:22 Updated: sssd-proxy-1.12.5-3.fc21.x86_64
Sep 05 20:48:23 Updated: rpm-4.12.0.1-7.fc21.x86_64
Sep 05 20:48:24 Updated: rpm-libs-4.12.0.1-7.fc21.x86_64
Sep 05 20:48:24 Updated: rpm-plugin-selinux-4.12.0.1-7.fc21.x86_64
Sep 05 20:48:24 Installed: drpm-0.2.0-2.fc21.x86_64
Sep 05 20:48:25 Updated: createrepo_c-libs-0.9.0-3.fc21.x86_64
Sep 05 20:48:26 Updated: rpm-build-libs-4.12.0.1-7.fc21.x86_64
Sep 05 20:48:26 Updated: rpm-python-4.12.0.1-7.fc21.x86_64
Sep 05 20:48:27 Updated: corosync-2.3.5-1.fc21.x86_64
Sep 05 20:48:27 Updated: corosynclib-2.3.5-1.fc21.x86_64
Sep 05 20:48:27 Updated: xen-licenses-4.4.2-9.fc21.x86_64
Sep 05 20:48:28 Updated: xen-libs-4.4.2-9.fc21.x86_64
Sep 05 20:48:29 Updated: 2:qemu-common-2.1.3-9.fc21.x86_64
Sep 05 20:48:31 Updated: 2:qemu-system-x86-2.1.3-9.fc21.x86_64
Sep 05 20:48:32 Updated: tzdata-java-2015f-1.fc21.noarch
Sep 05 20:48:32 Updated: hplip-common-3.14.10-9.fc21.x86_64
Sep 05 20:48:33 Updated: hplip-libs-3.14.10-9.fc21.x86_64
Sep 05 20:49:17 Updated: 1:hpijs-3.14.10-9.fc21.x86_64
Sep 05 20:49:18 Updated: qtlockedfile-2.4-18.20150629git5a07df5.fc21.x86_64
Sep 05 20:49:19 Updated: wxBase3-3.0.2-9.fc21.x86_64
Sep 05 20:49:20 Updated: gnome-menus-3.13.3-3.fc21.x86_64
Sep 05 20:49:20 Updated: 1:mariadb-config-10.0.21-1.fc21.x86_64
Sep 05 20:49:20 Updated: 1:mariadb-common-10.0.21-1.fc21.x86_64
Sep 05 20:49:21 Updated: 1:mariadb-errmsg-10.0.21-1.fc21.x86_64
Sep 05 20:49:21 Updated: libipa_hbac-1.12.5-3.fc21.x86_64
Sep 05 20:49:22 Updated: sssd-ipa-1.12.5-3.fc21.x86_64
Sep 05 20:49:22 Updated: lm_sensors-libs-3.3.5-6.fc21.x86_64
Sep 05 20:49:23 Updated: lm_sensors-3.3.5-6.fc21.x86_64
Sep 05 20:49:23 Updated: sssd-1.12.5-3.fc21.x86_64
Sep 05 20:49:24 Updated: 1:mariadb-embedded-10.0.21-1.fc21.x86_64
Sep 05 20:49:25 Updated: 1:mariadb-libs-10.0.21-1.fc21.x86_64
Sep 05 20:49:26 Updated: gnome-software-3.14.7-1.fc21.x86_64
Sep 05 20:49:28 Updated: wxGTK3-3.0.2-9.fc21.x86_64
Sep 05 20:49:28 Updated: qtsingleapplication-2.6.1-23.fc21.x86_64
Sep 05 20:49:30 Updated: hplip-3.14.10-9.fc21.x86_64
Sep 05 20:49:30 Updated: libsane-hpaio-3.14.10-9.fc21.x86_64
Sep 05 20:49:38 Updated: 1:java-1.8.0-openjdk-headless-1.8.0.51-5.b16.fc21.x86_64
Sep 05 20:49:38 Updated: 2:qemu-kvm-2.1.3-9.fc21.x86_64
Sep 05 20:49:39 Updated: 2:qemu-img-2.1.3-9.fc21.x86_64
Sep 05 20:49:39 Updated: 2:libcacard-2.1.3-9.fc21.x86_64
Sep 05 20:49:40 Updated: system-config-users-1.3.8-1.fc21.noarch
Sep 05 20:49:40 Updated: createrepo_c-0.9.0-3.fc21.x86_64
Sep 05 20:49:41 Updated: rpm-plugin-systemd-inhibit-4.12.0.1-7.fc21.x86_64
Sep 05 20:49:41 Updated: nss-tools-3.19.3-1.0.fc21.x86_64
Sep 05 20:49:42 Updated: pam_pkcs11-0.6.8-6.fc21.x86_64
Sep 05 20:49:54 Updated: firefox-40.0.3-1.fc21.x86_64
Sep 05 20:49:55 Updated: man-db-2.6.7.1-16.fc21.x86_64
Sep 05 20:49:56 Updated: httpd-2.4.16-1.fc21.x86_64
Sep 05 20:49:57 Updated: pavucontrol-2.0-9.fc21.x86_64
Sep 05 20:49:57 Updated: python3-slip-dbus-0.6.3-1.fc21.noarch
Sep 05 20:50:02 Updated: python-twisted-15.1.0-1.fc21.x86_64
Sep 05 20:50:03 Updated: python-fedmsg-meta-fedora-infrastructure-0.5.11-1.fc21.noarch
Sep 05 20:50:03 Updated: gnutls-utils-3.3.17-1.fc21.x86_64
Sep 05 20:50:37 Updated: wireshark-gnome-1.12.6-1.fc21.x86_64
Sep 05 20:50:38 Updated: elfutils-0.163-1.fc21.x86_64
Sep 05 20:50:39 Updated: system-config-printer-1.5.7-3.fc21.x86_64
Sep 05 20:50:40 Updated: ffmpeg-2.4.11-1.fc21.x86_64
Sep 05 20:50:40 Updated: python-slip-dbus-0.6.3-1.fc21.noarch
Sep 05 20:50:40 Installed: kernel-4.1.5-100.fc21.x86_64
Sep 05 20:50:41 Updated: open-vm-tools-desktop-9.10.2-1.fc21.x86_64
Sep 05 20:50:41 Updated: flac-1.3.1-5.fc21.x86_64
Sep 05 20:50:43 Updated: audacity-2.1.1-1.fc21.x86_64
Sep 05 20:50:44 Updated: sssd-libwbclient-1.12.5-3.fc21.x86_64
Sep 05 20:51:11 Updated: selinux-policy-devel-3.13.1-105.20.fc21.noarch
Sep 05 20:51:55 Updated: selinux-policy-targeted-3.13.1-105.20.fc21.noarch
Sep 05 20:51:56 Updated: system-config-printer-udev-1.5.7-3.fc21.x86_64
Sep 05 20:51:56 Updated: avahi-gobject-0.6.31-32.fc21.x86_64
Sep 05 20:51:57 Updated: avahi-ui-gtk3-0.6.31-32.fc21.x86_64
Sep 05 20:51:57 Updated: glusterfs-fuse-3.5.5-2.fc21.x86_64
Sep 05 20:51:58 Updated: openssh-clients-6.6.1p1-16.fc21.x86_64
Sep 05 20:51:58 Updated: openssh-askpass-6.6.1p1-16.fc21.x86_64
Sep 05 20:51:58 Updated: openssh-server-6.6.1p1-16.fc21.x86_64
Sep 05 20:51:59 Updated: avahi-0.6.31-32.fc21.x86_64
Sep 05 20:52:00 Updated: audit-libs-python-2.4.4-1.fc21.x86_64
Sep 05 20:52:00 Updated: audit-2.4.4-1.fc21.x86_64
Sep 05 20:52:01 Updated: avahi-autoipd-0.6.31-32.fc21.x86_64
Sep 05 20:52:01 Updated: systemtap-sdt-devel-2.8-1.fc21.x86_64
Sep 05 20:52:05 Updated: 2:gedit-3.14.4-1.fc21.x86_64
Sep 05 20:52:05 Updated: 1:smartmontools-6.4-2.fc21.x86_64
Sep 05 20:52:06 Updated: libselinux-utils-2.3-10.fc21.x86_64
Sep 05 20:52:07 Updated: parted-3.2-9.fc21.x86_64
Sep 05 20:52:07 Updated: 1:wpa_supplicant-2.0-14.fc21.x86_64
Sep 05 20:52:08 Updated: 1:openssl-1.0.1k-12.fc21.x86_64
Sep 05 20:52:10 Updated: 1:xrdp-0.6.1-11.fc21.x86_64
Sep 05 20:52:11 Updated: openvpn-2.3.8-1.fc21.x86_64
Sep 05 20:52:12 Updated: xfsprogs-3.2.2-2.fc21.x86_64
Sep 05 20:52:13 Updated: flash-plugin-11.2.202.508-release.x86_64
Sep 05 20:52:13 Updated: jwhois-4.0-42.fc21.x86_64
Sep 05 20:52:14 Updated: 2:qemu-guest-agent-2.1.3-9.fc21.x86_64
Sep 05 20:52:15 Updated: libsolv-0.6.11-2.fc21.x86_64
Sep 05 20:52:15 Updated: unoconv-0.7-1.fc21.noarch
Sep 05 20:52:20 Updated: man-pages-3.69-5.fc21.noarch
Sep 05 20:52:22 Updated: tzdata-2015f-1.fc21.noarch
Sep 05 20:52:22 Updated: hwdata-0.280-1.fc21.noarch
Sep 05 20:52:23 Updated: libvisio-0.1.3-1.fc21.x86_64
Sep 05 20:52:25 Updated: kernel-headers-4.1.5-100.fc21.x86_64
Sep 05 20:52:25 Updated: lz4-r131-1.fc21.x86_64
Sep 05 20:52:26 Updated: libspectre-0.2.7-6.fc21.x86_64
Sep 05 20:52:26 Updated: stoken-libs-0.90-2.fc21.x86_64
Sep 05 20:52:27 Updated: perl-HTTP-Message-6.10-1.fc21.noarch
Sep 05 20:52:27 Updated: xorg-x11-drv-wacom-0.25.0-3.fc21.x86_64
Sep 05 20:52:28 Updated: libwmf-lite-0.2.8.4-45.fc21.x86_64
Sep 05 20:52:29 Updated: subversion-libs-1.8.13-7.fc21.x86_64
Sep 05 20:52:29 Updated: libunwind-1.1-10.fc21.x86_64
Sep 05 20:52:30 Updated: sg3_utils-libs-1.41-1.fc21.x86_64
Sep 05 20:52:31 Updated: rubygems-2.2.5-100.fc21.noarch
Sep 05 20:52:31 Updated: elfutils-libelf-0.163-1.fc21.i686
Sep 05 20:52:31 Updated: elfutils-libs-0.163-1.fc21.i686
Sep 05 20:52:32 Updated: flac-libs-1.3.1-5.fc21.i686
Sep 05 20:52:33 Updated: libselinux-2.3-10.fc21.i686
Sep 05 20:52:33 Updated: audit-libs-2.4.4-1.fc21.i686
Sep 05 20:52:33 Updated: 1:dbus-libs-1.8.20-1.fc21.i686