我尝试使用VirtualBox作为提供程序，ansible作为配置工具，来启动一个CentOS机器（
centos7-x64-vbox43）的虚拟化环境。我执行了如下命令：
vagrant up --provision-with ansible
但我遇到了一个错误，与在虚拟机中执行以下命令 yum -y install nfs-utils nfs-utils-lib 有关：
[project-name] > vagrant up
/opt/vagrant/embedded/gems/gems/vagrant-1.8.1/lib/vagrant/pre-rubygems.rb:31: warning: Insecure world writable dir /Applications/Qt in PATH, mode 040777
/opt/vagrant/embedded/gems/gems/bundler-1.10.6/lib/bundler/shared_helpers.rb:78: warning: Insecure world writable dir /Applications/Qt in PATH, mode 040777
Bringing machine 'default' up with 'virtualbox' provider...
==> default: Clearing any previously set forwarded ports...
==> default: Clearing any previously set network interfaces...
==> default: Preparing network interfaces based on configuration...
default: Adapter 1: nat
default: Adapter 2: hostonly
==> default: Forwarding ports...
default: 80 (guest) => 2000 (host) (adapter 1)
default: 22 (guest) => 2222 (host) (adapter 1)
==> default: Running 'pre-boot' VM customizations...
==> default: Booting VM...
==> default: Waiting for machine to boot. This may take a few minutes...
default: SSH address: 127.0.0.1:2222
default: SSH username: vagrant
default: SSH auth method: private key
default: Warning: Remote connection disconnect. Retrying...
==> default: Machine booted and ready!
==> default: Checking for guest additions in VM...
default: The guest additions on this VM do not match the installed version of
default: VirtualBox! In most cases this is fine, but in rare cases it can
default: prevent things such as shared folders from working properly. If you see
default: shared folder errors, please make sure the guest additions within the
default: virtual machine match the version of VirtualBox you have installed on
default: your host and reload your VM.
default:
default: Guest Additions Version: 4.3.14
default: VirtualBox Version: 5.0
==> default: Setting hostname...
==> default: Configuring and enabling network interfaces...
==> default: Installing NFS client...
The following SSH command responded with a non-zero exit status.
Vagrant assumes that this means the command failed!
yum -y install nfs-utils nfs-utils-lib
Stdout from the command:
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
* base: mirror.switch.ch
* extras: mirror.ratiokontakt.de
* updates: mirror.ratiokontakt.de
No package nfs-utils-lib available.
Resolving Dependencies
--> Running transaction check
---> Package nfs-utils.x86_64 1:1.3.0-0.21.el7_2.1 will be installed
--> Processing Dependency: libtirpc >= 0.2.3-1 for package: 1:nfs-utils-1.3.0-0.21.el7_2.1.x86_64
--> Processing Dependency: gssproxy >= 0.3.0-0 for package: 1:nfs-utils-1.3.0-0.21.el7_2.1.x86_64
--> Processing Dependency: rpcbind for package: 1:nfs-utils-1.3.0-0.21.el7_2.1.x86_64
--> Processing Dependency: quota for package: 1:nfs-utils-1.3.0-0.21.el7_2.1.x86_64
--> Processing Dependency: libnfsidmap for package: 1:nfs-utils-1.3.0-0.21.el7_2.1.x86_64
--> Processing Dependency: libevent for package: 1:nfs-utils-1.3.0-0.21.el7_2.1.x86_64
--> Processing Dependency: libdevmapper.so.1.02(DM_1_02_97)(64bit) for package: 1:nfs-utils-1.3.0-0.21.el7_2.1.x86_64
--> Processing Dependency: keyutils for package: 1:nfs-utils-1.3.0-0.21.el7_2.1.x86_64
--> Processing Dependency: libtirpc.so.1()(64bit) for package: 1:nfs-utils-1.3.0-0.21.el7_2.1.x86_64
--> Processing Dependency: libnfsidmap.so.0()(64bit) for package: 1:nfs-utils-1.3.0-0.21.el7_2.1.x86_64
--> Processing Dependency: libevent-2.0.so.5()(64bit) for package: 1:nfs-utils-1.3.0-0.21.el7_2.1.x86_64
--> Running transaction check
---> Package device-mapper-libs.x86_64 7:1.02.84-14.el7 will be updated
--> Processing Dependency: device-mapper-libs = 7:1.02.84-14.el7 for package: 7:device-mapper-1.02.84-14.el7.x86_64
---> Package device-mapper-libs.x86_64 7:1.02.107-5.el7_2.5 will be an update
---> Package gssproxy.x86_64 0:0.4.1-7.el7 will be installed
--> Processing Dependency: krb5-libs >= 1.12.0 for package: gssproxy-0.4.1-7.el7.x86_64
--> Processing Dependency: libverto-tevent for package: gssproxy-0.4.1-7.el7.x86_64
--> Processing Dependency: libini_config.so.3(INI_CONFIG_1.1.0)(64bit) for package: gssproxy-0.4.1-7.el7.x86_64
--> Processing Dependency: libref_array.so.1()(64bit) for package: gssproxy-0.4.1-7.el7.x86_64
--> Processing Dependency: libini_config.so.3()(64bit) for package: gssproxy-0.4.1-7.el7.x86_64
--> Processing Dependency: libcollection.so.2()(64bit) for package: gssproxy-0.4.1-7.el7.x86_64
--> Processing Dependency: libbasicobjects.so.0()(64bit) for package: gssproxy-0.4.1-7.el7.x86_64
---> Package keyutils.x86_64 0:1.5.8-3.el7 will be installed
---> Package libevent.x86_64 0:2.0.21-4.el7 will be installed
---> Package libnfsidmap.x86_64 0:0.25-12.el7 will be installed
---> Package libtirpc.x86_64 0:0.2.4-0.6.el7 will be installed
---> Package quota.x86_64 1:4.01-11.el7_2.1 will be installed
--> Processing Dependency: quota-nls = 1:4.01-11.el7_2.1 for package: 1:quota-4.01-11.el7_2.1.x86_64
--> Processing Dependency: tcp_wrappers for package: 1:quota-4.01-11.el7_2.1.x86_64
---> Package rpcbind.x86_64 0:0.2.0-33.el7_2.1 will be installed
--> Processing Dependency: libsystemd.so.0(LIBSYSTEMD_209)(64bit) for package: rpcbind-0.2.0-33.el7_2.1.x86_64
--> Processing Dependency: libsystemd.so.0()(64bit) for package: rpcbind-0.2.0-33.el7_2.1.x86_64
--> Running transaction check
---> Package device-mapper.x86_64 7:1.02.84-14.el7 will be updated
--> Processing Dependency: device-mapper = 7:1.02.84-14.el7 for package: 7:device-mapper-event-1.02.84-14.el7.x86_64
---> Package device-mapper.x86_64 7:1.02.107-5.el7_2.5 will be an update
---> Package krb5-libs.x86_64 0:1.11.3-49.el7 will be updated
---> Package krb5-libs.x86_64 0:1.13.2-12.el7_2 will be an update
---> Package libbasicobjects.x86_64 0:0.1.1-25.el7 will be installed
---> Package libcollection.x86_64 0:0.6.2-25.el7 will be installed
---> Package libini_config.x86_64 0:1.2.0-25.el7 will be installed
--> Processing Dependency: libpath_utils.so.1(PATH_UTILS_0.2.1)(64bit) for package: libini_config-1.2.0-25.el7.x86_64
--> Processing Dependency: libpath_utils.so.1()(64bit) for package: libini_config-1.2.0-25.el7.x86_64
---> Package libref_array.x86_64 0:0.1.5-25.el7 will be installed
---> Package libverto-tevent.x86_64 0:0.2.5-4.el7 will be installed
--> Processing Dependency: libtevent.so.0(TEVENT_0.9.9)(64bit) for package: libverto-tevent-0.2.5-4.el7.x86_64
--> Processing Dependency: libtalloc.so.2(TALLOC_2.0.2)(64bit) for package: libverto-tevent-0.2.5-4.el7.x86_64
--> Processing Dependency: libtevent.so.0()(64bit) for package: libverto-tevent-0.2.5-4.el7.x86_64
--> Processing Dependency: libtalloc.so.2()(64bit) for package: libverto-tevent-0.2.5-4.el7.x86_64
---> Package quota-nls.noarch 1:4.01-11.el7_2.1 will be installed
---> Package systemd-libs.x86_64 0:208-11.el7_0.2 will be updated
--> Processing Dependency: systemd-libs = 208-11.el7_0.2 for package: systemd-208-11.el7_0.2.x86_64
---> Package systemd-libs.x86_64 0:219-19.el7_2.11 will be an update
---> Package tcp_wrappers.x86_64 0:7.6-77.el7 will be installed
--> Running transaction check
---> Package device-mapper-event.x86_64 7:1.02.84-14.el7 will be updated
---> Package device-mapper-event.x86_64 7:1.02.107-5.el7_2.5 will be an update
--> Processing Dependency: device-mapper-event-libs = 7:1.02.107-5.el7_2.5 for package: 7:device-mapper-event-1.02.107-5.el7_2.5.x86_64
---> Package libpath_utils.x86_64 0:0.2.1-25.el7 will be installed
---> Package libtalloc.x86_64 0:2.1.5-1.el7_2 will be installed
---> Package libtevent.x86_64 0:0.9.26-1.el7_2.1 will be installed
---> Package systemd.x86_64 0:208-11.el7_0.2 will be updated
--> Processing Dependency: systemd = 208-11.el7_0.2 for package: systemd-sysv-208-11.el7_0.2.x86_64
--> Processing Dependency: systemd = 208-11.el7_0.2 for package: libgudev1-208-11.el7_0.2.x86_64
---> Package systemd.x86_64 0:219-19.el7_2.11 will be an update
--> Processing Dependency: kmod >= 18-4 for package: systemd-219-19.el7_2.11.x86_64
--> Running transaction check
---> Package device-mapper-event-libs.x86_64 7:1.02.84-14.el7 will be updated
---> Package device-mapper-event-libs.x86_64 7:1.02.107-5.el7_2.5 will be an update
---> Package kmod.x86_64 0:14-9.el7 will be updated
---> Package kmod.x86_64 0:20-5.el7 will be an update
---> Package libgudev1.x86_64 0:208-11.el7_0.2 will be updated
---> Package libgudev1.x86_64 0:219-19.el7_2.11 will be an update
---> Package systemd-sysv.x86_64 0:208-11.el7_0.2 will be updated
---> Package systemd-sysv.x86_64 0:219-19.el7_2.11 will be an update
--> Processing Conflict: systemd-219-19.el7_2.11.x86_64 conflicts initscripts < 9.49.28-1
--> Restarting Dependency Resolution with new changes.
--> Running transaction check
---> Package initscripts.x86_64 0:9.49.17-1.el7 will be updated
---> Package initscripts.x86_64 0:9.49.30-1.el7_2.2 will be an update
--> Processing Conflict: systemd-219-19.el7_2.11.x86_64 conflicts dracut < 033-243
--> Restarting Dependency Resolution with new changes.
--> Running transaction check
---> Package dracut.x86_64 0:033-161.el7 will be updated
--> Processing Dependency: dracut = 033-161.el7 for package: dracut-config-rescue-033-161.el7.x86_64
--> Processing Dependency: dracut = 033-161.el7 for package: dracut-network-033-161.el7.x86_64
---> Package dracut.x86_64 0:033-360.el7_2.1 will be an update
--> Running transaction check
---> Package dracut-config-rescue.x86_64 0:033-161.el7 will be updated
---> Package dracut-config-rescue.x86_64 0:033-360.el7_2.1 will be an update
---> Package dracut-network.x86_64 0:033-161.el7 will be updated
---> Package dracut-network.x86_64 0:033-360.el7_2.1 will be an update
--> Finished Dependency Resolution
Dependencies Resolved
================================================================================
Package Arch Version Repository Size
================================================================================
Installing:
nfs-utils x86_64 1:1.3.0-0.21.el7_2.1 updates 371 k
Updating:
dracut x86_64 033-360.el7_2.1 updates 311 k
initscripts x86_64 9.49.30-1.el7_2.2 updates 429 k
Installing for dependencies:
gssproxy x86_64 0.4.1-7.el7 base 84 k
keyutils x86_64 1.5.8-3.el7 base 54 k
libbasicobjects x86_64 0.1.1-25.el7 base 24 k
libcollection x86_64 0.6.2-25.el7 base 40 k
libevent x86_64 2.0.21-4.el7 base 214 k
libini_config x86_64 1.2.0-25.el7 base 59 k
libnfsidmap x86_64 0.25-12.el7 base 46 k
libpath_utils x86_64 0.2.1-25.el7 base 27 k
libref_array x86_64 0.1.5-25.el7 base 26 k
libtalloc x86_64 2.1.5-1.el7_2 updates 34 k
libtevent x86_64 0.9.26-1.el7_2.1 updates 33 k
libtirpc x86_64 0.2.4-0.6.el7 base 85 k
libverto-tevent x86_64 0.2.5-4.el7 base 9.0 k
quota x86_64 1:4.01-11.el7_2.1 updates 178 k
quota-nls noarch 1:4.01-11.el7_2.1 updates 90 k
rpcbind x86_64 0.2.0-33.el7_2.1 updates 58 k
tcp_wrappers x86_64 7.6-77.el7 base 78 k
Updating for dependencies:
device-mapper x86_64 7:1.02.107-5.el7_2.5 updates 252 k
device-mapper-event x86_64 7:1.02.107-5.el7_2.5 updates 167 k
device-mapper-event-libs x86_64 7:1.02.107-5.el7_2.5 updates 169 k
device-mapper-libs x86_64 7:1.02.107-5.el7_2.5 updates 305 k
dracut-config-rescue x86_64 033-360.el7_2.1 updates 50 k
dracut-network x86_64 033-360.el7_2.1 updates 90 k
kmod x86_64 20-5.el7 base 114 k
krb5-libs x86_64 1.13.2-12.el7_2 updates 843 k
libgudev1 x86_64 219-19.el7_2.11 updates 66 k
systemd x86_64 219-19.el7_2.11 updates 5.1 M
systemd-libs x86_64 219-19.el7_2.11 updates 358 k
systemd-sysv x86_64 219-19.el7_2.11 updates 53 k
Transaction Summary
================================================================================
Install 1 Package (+17 Dependent packages)
Upgrade 2 Packages (+12 Dependent packages)
Total size: 9.8 M
Downloading packages:
Running transaction check
Running transaction test
Stderr from the command:
Transaction check error:
file /usr/lib/systemd/system/blk-availability.service from install of device-mapper-7:1.02.107-5.el7_2.5.x86_64 conflicts with file from package lvm2-7:2.02.105-14.el7.x86_64
file /usr/sbin/blkdeactivate from install of device-mapper-7:1.02.107-5.el7_2.5.x86_64 conflicts with file from package lvm2-7:2.02.105-14.el7.x86_64
file /usr/share/man/man8/blkdeactivate.8.gz from install of device-mapper-7:1.02.107-5.el7_2.5.x86_64 conflicts with file from package lvm2-7:2.02.105-14.el7.x86_64
Error Summary
-------------
我对此原因并不清楚，因为我对 vagrant 并不是很熟悉，我只使用过两三次。那么我的第一个问题是：为什么会出现这种情况呢？
请注意，我认为我知道什么是 NFS，即它应该是一个挂载在客户机上的文件系统，允许同一台机器和主机共享文件夹和文件，对吗？
直到我找到了以下文章，我才能解决这个问题：
至少对我来说，这个标题似乎与上面的问题没有任何关系。
我意识到，在上面的命令失败后，vagrant 机器实际上已经被初始化，我可以使用 vagrant ssh 连接到它，这就是我所做的。然后，在客户 vagrant 机器中（在执行 vagrant ssh 后），我执行了以下命令（这些命令与我刚提到的文章中指定的命令相同）：
sudo yum install yum-utils
sudo package-cleanup --dupes
sudo package-cleanup --cleandupes
添加了这行代码：
exactarch=1
将内容添加到文件/etc/yum.conf，最后执行。
yum clean all
sudo yum update
我通过输入exit退出了vagrant虚拟机。我使用vagrant halt停止了虚拟机。然后我重新执行了最初的命令：
vagrant up --provision-with ansible
错误不再出现了。
我的第二个问题是：为什么执行上述教程中提到的命令以及我明确提到的命令可以解决问题？
当执行删除重复软件包的命令时，我注意到输出实际上并没有发现有重复的软件包。在我的情况下，似乎真正解决问题的命令只有（不确定）：
yum clean all
sudo yum update
为什么这会真正解决问题？
我的一个想法是，这个盒子实际上已经过时了，因为将预安装的软件包更新到最新版本显然解决了问题...