不能安装任何软件包

Question

无论我试图安装哪个软件包，Yum都会为每个包/依赖项返回一个[Errno 5] [Errno 2] No such file or directory error。

下面是一些示例输出：

# yum -y install vim
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
 * base: mirrors.ocf.berkeley.edu
 * extras: mirror.tocici.com
 * updates: mirror.sesp.northwestern.edu
Resolving Dependencies
--> Running transaction check
---> Package vim-enhanced.x86_64 2:7.4.160-1.el7_3.1 will be installed
--> Processing Dependency: vim-common = 2:7.4.160-1.el7_3.1 for package: 2:vim-enhanced-7.4.160-1.el7_3.1.x86_64
--> Processing Dependency: libgpm.so.2()(64bit) for package: 2:vim-enhanced-7.4.160-1.el7_3.1.x86_64
--> Running transaction check
---> Package gpm-libs.x86_64 0:1.20.7-5.el7 will be installed
---> Package vim-common.x86_64 2:7.4.160-1.el7_3.1 will be installed
--> Processing Dependency: vim-filesystem for package: 2:vim-common-7.4.160-1.el7_3.1.x86_64
--> Running transaction check
---> Package vim-filesystem.x86_64 2:7.4.160-1.el7_3.1 will be installed
--> Finished Dependency Resolution

Dependencies Resolved

==============================================================================================================================================================================================================================================
 Package                                                     Arch                                                Version                                                           Repository                                            Size
==============================================================================================================================================================================================================================================
Installing:
 vim-enhanced                                                x86_64                                              2:7.4.160-1.el7_3.1                                               updates                                              1.0 M
Installing for dependencies:
 gpm-libs                                                    x86_64                                              1.20.7-5.el7                                                      base                                                  32 k
 vim-common                                                  x86_64                                              2:7.4.160-1.el7_3.1                                               updates                                              5.9 M
 vim-filesystem                                              x86_64                                              2:7.4.160-1.el7_3.1                                               updates                                              9.7 k

Transaction Summary
==============================================================================================================================================================================================================================================
Install  1 Package (+3 Dependent packages)

Total download size: 7.0 M
Installed size: 23 M
Downloading packages:


Error downloading packages:
  gpm-libs-1.20.7-5.el7.x86_64: [Errno 5] [Errno 2] No such file or directory
  2:vim-filesystem-7.4.160-1.el7_3.1.x86_64: [Errno 5] [Errno 2] No such file or directory
  2:vim-enhanced-7.4.160-1.el7_3.1.x86_64: [Errno 5] [Errno 2] No such file or directory
  2:vim-common-7.4.160-1.el7_3.1.x86_64: [Errno 5] [Errno 2] No such file or directory

它看起来像是能够连接到存储库并看到所需的包/依赖项，但是当它下载时就失败了。我不太了解如何管理repos和yum，但看起来这可能是本地机器上的一个问题吗？

发行版是AWS上的CentOS Linux版本7.2.1511 (Core)。

Answer 1

在其中一个服务器上，我注意到文件/usr/libexec/urlgrabber-ext-down的顶部是#! /usr/bin/python

但是蟒蛇的符号连接被破坏了。键入python --version将引发一个错误，即command not found

为python创建了指向python2.7的符号链接，并修复了这个问题

Answer 2

你应该没事的

ln -s /usr/libexec/urlgrabber-ext-down-2.7 /usr/libexec/urlgrabber-ext-down

Answer 3

如果您阅读yum和urlgrabber的源代码，您会发现：

yum使用python模块urlgrabber下载rpm包，其高级异步api parallel_wait与包_ExternalDownloader的内部类相关联。

urlgrabber-ext-down's dir是在_ExternalDownloader类中编写的硬代码，在urlgrabber/grabber.py的第2075行中作为/usr/libexec/urlgrabber-ext-down编写。

def __init__(self)：self.popen = subprocess.Popen(‘/usr/libexec/urlgrabber-ext’，stdin = subprocess.PIPE，stdout = subprocess.PIPE，) self.stdin = self.popen.stdin.fileno() self.stdout = self.popen.stdout.fileno() self.running = {} self.cnt =0

所以，只需确保您的urlgrabber-ext-down就在那里，或者重写代码行2075。