造成的原因是之前对python进行了一个备份，当python出现多版本也会出现这个情况
[root@localhost bin]# yum -bash: /usr/bin/yum: /usr/bin/python: bad interpreter: No such file or directory [root@localhost bin]# whereis python python: /usr/bin/python2.6 /usr/bin/python.bak /usr/lib/python2.6 /usr/lib64/python2.6 /usr/include/python2.6 /usr/share/man/man1/python.1.gz [root@localhost bin]# whereis yum yum: /usr/bin/yum /etc/yum /etc/yum.conf /usr/share/man/man8/yum.8.gz [root@localhost bin]# mv python.bak python [root@localhost bin]# whereis python python: /usr/bin/python2.6 /usr/bin/python /usr/lib/python2.6 /usr/lib64/python2.6 /usr/include/python2.6 /usr/share/man/man1/python.1.gz [root@localhost bin]# yum Loaded plugins: fastestmirror, refresh-packagekit, security You need to give some command Usage: yum [options] COMMAND List of Commands: check Check for problems in the rpmdb check-update Check for available package updates clean Remove cached data deplist List a package's dependencies distribution-synchronization Synchronize installed packages to the latest available versions downgrade downgrade a package erase Remove a package or packages from your system