$ sudo yum list

Loaded plugins: fastestmirror, langpacks

Repository base is listed more than once in the configuration

Repository updates is listed more than once in the configuration

Repository extras is listed more than once in the configuration

Repository centosplus is listed more than once in the configuration

Repository base is listed more than once in the configuration

Repository updates is listed more than once in the configuration

Repository extras is listed more than once in the configuration

Repository centosplus is listed more than once in the configuration

File contains parsing errors: file:///etc/yum.repos.d/fedora.repo

..................

 

使用yum 安装软件(或者执行yum list)时报以上错误，从错误提示中可以看出是一些插件和包被重复设置了。

猜测可能是因为yum源(我的yum源有很多个)之间重复设置了某个包的安装地址。于是把所有的yum源都改个名字，把.repo后缀改成.repo.bk后缀。保留一个比较常用的：

$ su root

#cd /etc/yum.repos.d

# ls

CentOS7-Base-163.repo     CentOS-CR.repo         CentOS-Media.repo    fedora.repo

CentOS-Base.repo       CentOS-Debuginfo.repo  CentOS-Sources.repo

CentOS-Base-sohu.repo CentOS-fasttrack.repo CentOS-Vault.repo

#rename .repo .repo.bk *.repo

#mv CentOS7-Base-163.repo.bk CentOS7-Base-163.repo

# ls

CentOS7-Base-163.repo     CentOS-CR.repo.bk         CentOS-Media.repo.bk    fedora.repo.bk

CentOS-Base.repo.bk       CentOS-Debuginfo.repo.bk  CentOS-Sources.repo.bk

CentOS-Base-sohu.repo.bk  CentOS-fasttrack.repo.bk  CentOS-Vault.repo.bk

#yum list

ant-commons-logging.noarch                                1.9.2-9.el7                          base     

ant-commons-net.noarch                                    1.9.2-9.el7                          base     

ant-contrib.noarch                                        1.0-0.23.b3.el7                      base     

ant-contrib-javadoc.noarch                                1.0-0.23.b3.el7                      base     

ant-javadoc.noarch                                        1.9.2-9.el7                          base     

ant-javamail.noarch                                       1.9.2-9.el7                          base     

ant-jdepend.noarch                                        1.9.2-9.el7                          base     

ant-jmf.noarch                                            1.9.2-9.el7                          base     

ant-jsch.noarch                                           1.9.2-9.el7                          base     

ant-junit.noarch                                          1.9.2-9.el7                          base     

ant-manual.noarch                                         1.9.2-9.el7                          base     

ant-swing.noarch                                          1.9.2-9.el7                          base     

ant-testutil.noarch                                       1.9.2-9.el7                          base     

antlr-C++.i686                                            2.7.7-30.el7                         base     

antlr-C++.x86_64                                          2.7.7-30.el7                         base     

antlr-C++-doc.noarch                                      2.7.7-30.el7                         base     

antlr-javadoc.noarch                                      2.7.7-30.el7                         base     

antlr-manual.noarch                                       2.7.7-30.el7                         base 

........

这样的话，原来的错误就解决了。如果有些包安装不成功，也不在yum list的列表里面，就配置一个和所需包对应的yum源吧