[DRPM] rpm-4.12.0.1-9.fc22_4.12.0.1-11.fc22.x86_64.drpm: done                                                                                                                                                     
[DRPM] satyr-0.16-1.fc22_0.18-1.fc22.i686.drpm: done                                                                                                                                                              
[DRPM] satyr-0.16-1.fc22_0.18-1.fc22.x86_64.drpm: done                                                                                                                                                            
[DRPM] spice-gtk3-0.28-3.fc22_0.29-1.fc22.x86_64.drpm: done                                                                                                                                                       
[DRPM] sane-backends-1.0.24-13.fc22_1.0.24-14.fc22.x86_64.drpm: done                                                                                                                                              
[DRPM] subunit-1.0.0-1.fc22_1.1.0-1.fc22.x86_64.drpm: done                                                                                                                                                        
[DRPM] spice-glib-0.28-3.fc22_0.29-1.fc22.x86_64.drpm: done                                                                                                                                                       
[DRPM] tzdata-java-2015d-1.fc22_2015e-1.fc22.noarch.drpm: done                                                                                                                                                    
[DRPM] unbound-libs-1.5.3-4.fc22_1.5.3-8.fc22.x86_64.drpm: done                                                                                                                                                   
[DRPM] xorg-x11-drv-intel-2.99.917-11.20150603.fc22_2.99.917-12.20150615.fc22.x86_64.drpm: done                                                                                                                   
[DRPM] zeromq-4.0.5-3.fc22_4.0.5-4.fc22.x86_64.drpm: done                                                                                                                                                         
[DRPM] xen-libs-4.5.0-10.fc22_4.5.0-11.fc22.x86_64.drpm: done                                                                                                                                                     
[DRPM] phpMyAdmin-4.4.9-1.fc22_4.4.10-1.fc22.noarch.drpm: done                                                                                                                                                    
Error: Error downloading packages:
  Cannot download flash-plugin-11.2.202.468-release.x86_64.rpm: All mirrors were tried
[octopus@pc3 ~]$

就因为adobe flash那个软件包无法下载，所以其他所有的软件包都无法更新，再执行dnf update，所有软件包都得重新下载：
[octopus@pc3 ~]$ sudo yum update
[sudo] password for octopus:
Yum command has been deprecated, redirecting to '/usr/bin/dnf update'.
See 'man dnf' and 'man yum2dnf' for more information.
To transfer transaction metadata from yum to DNF, run:
'dnf install python-dnf-plugins-extras-migrate && dnf-2 migrate'

Last metadata expiration check performed 0:12:14 ago on Thu Jul  2 18:28:34 2015.
Dependencies resolved.
===================================================================================================================================================================================================================
 Package                                                       Arch                                 Version                                                 Repository                                        Size
===================================================================================================================================================================================================================
Installing:
 kernel                                                        x86_64                               4.0.6-300.fc22                                          updates                                           66 k
 kernel-core                                                   x86_64                               4.0.6-300.fc22                                          updates                                           19 M
 kernel-devel                                                  x86_64                               4.0.6-300.fc22                                          updates                                          9.4 M
 kernel-modules                                                x86_64                               4.0.6-300.fc22                                          updates                                           18 M
 kernel-modules-extra                                          x86_64                               4.0.6-300.fc22                                          updates                                          2.2 M
 lksctp-tools                                                  x86_64                               1.0.16-3.fc22                                           fedora                                            93 k
Upgrading:
 PackageKit                                                    x86_64                               1.0.6-6.fc22                                            updates                                          576 k
 PackageKit-cached-metadata                                    x86_64                               1.0.6-6.fc22                                            updates                                           69 M
 PackageKit-command-not-found                                  x86_64                               1.0.6-6.fc22                                            updates                                           28 k
 PackageKit-glib                                               x86_64                               1.0.6-6.fc22                                            updates                                          133 k
 PackageKit-gstreamer-plugin                                   x86_64                               1.0.6-6.fc22                                            updates                                           20 k
 PackageKit-gtk3-module                                        x86_64                               1.0.6-6.fc22                                            updates                                           21 k
 abrt                                                          x86_64                               2.6.0-1.fc22                                            updates                                          516 k
 abrt-addon-ccpp                                               x86_64                               2.6.0-1.fc22                                            updates                                          186 k
 abrt-addon-coredump-helper                                    x86_64                               2.6.0-1.fc22                                            updates                                          104 k
 abrt-addon-kerneloops                                         x86_64                               2.6.0-1.fc22                                            updates                                          121 k
 abrt-addon-pstoreoops                                         x86_64                               2.6.0-1.fc22                                            updates                                          100 k
 abrt-addon-python                                             x86_64                               2.6.0-1.fc22                                            updates                       

而且update也需要翻墙！

[octopus@pc3 ~]$ sudo dnf -y upgrade
[sudo] password for octopus:
Last metadata expiration check performed 2:00:51 ago on Fri Jul 10 17:50:29 2015.
Dependencies resolved.
================================================================================
 Package               Arch    Version                Repository           Size
================================================================================
Upgrading:
 file-roller           x86_64  3.16.3-1.fc22          updates             911 k
 file-roller-nautilus  x86_64  3.16.3-1.fc22          updates              35 k
 flash-plugin          x86_64  11.2.202.481-release   adobe-linux-x86_64  6.9 M
 google-chrome-stable  x86_64  43.0.2357.132-1        google-chrome        46 M
 openjpeg2             x86_64  2.1.0-5.fc22           updates             108 k

Transaction Summary
================================================================================
Upgrade  5 Packages

Total download size: 54 M
Downloading Packages:
(1/5): file-roller-nautilus-3.16.3-1.fc22.x86_6  45 kB/s |  35 kB     00:00    
(2/5): file-roller-3.16.2-1.fc22_3.16.3-1.fc22. 296 kB/s | 302 kB     00:01    
(3/5): openjpeg2-2.1.0-5.fc22.x86_64.rpm         99 kB/s | 108 kB     00:01    
(4/5): google-chrome-stable-43.0.2357.132-1.x86 1.2 MB/s |  46 MB     00:37    
[MIRROR] flash-plugin-11.2.202.481-release.x86_64.rpm: Curl error (28): Timeout was reached for http://linuxdownload.adobe.com/linux/x86_64/flash-plugin-11.2.202.481-release.x86_64.rpm [Operation too slow. Less than 1000 bytes/sec transferred the last 120 seconds]
[FAILED] flash-plugin-11.2.202.481-release.x86_64.rpm: No more mirrors to try - All mirrors were already tried without success
[DRPM] file-roller-3.16.2-1.fc22_3.16.3-1.fc22.x86_64.drpm: done               
Error: Error downloading packages:
  Cannot download flash-plugin-11.2.202.481-release.x86_64.rpm: All mirrors were tried
[octopus@pc3 ~]$

问题主要出在flash插件上。