“/var/run/yum.pid 已被锁定”和“cannot open Packages database in /var/lib/rpm”

问题描述：

已加载插件：fastestmirror, refresh-packagekit, security
/var/run/yum.pid 已被锁定，PID 为 17148 的另一个程序正在运行。
另外一个程序锁定了 yum；等待它退出……
  The other application is: yum
    Memory : 196 M RSS (211 MB VSZ)
    Started: Thu Aug 22 20:13:54 2019 - 32:42 ago
    State  : Uninterruptible, pid: 17148
另外一个程序锁定了 yum；等待它退出……
  The other application is: yum
    Memory : 196 M RSS (211 MB VSZ)
    Started: Thu Aug 22 20:13:54 2019 - 32:44 ago
    State  : Uninterruptible, pid: 17148
另外一个程序锁定了 yum；等待它退出……
  The other application is: yum
    Memory : 202 M RSS (217 MB VSZ)
    Started: Thu Aug 22 20:13:54 2019 - 32:46 ago
    State  : Running, pid: 17148
另外一个程序锁定了 yum；等待它退出……
  The other application is: yum
    Memory : 202 M RSS (217 MB VSZ)
    Started: Thu Aug 22 20:13:54 2019 - 32:48 ago
    State  : Running, pid: 17148
另外一个程序锁定了 yum；等待它退出……
  The other application is: yum
    Memory : 202 M RSS (217 MB VSZ)
    Started: Thu Aug 22 20:13:54 2019 - 32:50 ago
    State  : Running, pid: 17148
另外一个程序锁定了 yum；等待它退出……
  The other application is: yum
    Memory : 207 M RSS (222 MB VSZ)
    Started: Thu Aug 22 20:13:54 2019 - 32:52 ago
    State  : Uninterruptible, pid: 17148

解决办法：

rm -fr /var/run/yum.pid

删除此文件后，可能报错

rpmdb: Thread/process 17148/3077801664 failed: Thread died in Berkeley DB library
error: db3 error(-30974) from dbenv->failchk: DB_RUNRECOVERY: Fatal error, run database recovery
error: cannot open Packages index using db3 -  (-30974)
error: cannot open Packages database in /var/lib/rpm
CRITICAL:yum.main:

Error: rpmdb open failed
[root@localhost run]# yum install php -y
rpmdb: Thread/process 17148/3077801664 failed: Thread died in Berkeley DB library
error: db3 error(-30974) from dbenv->failchk: DB_RUNRECOVERY: Fatal error, run database recovery
error: cannot open Packages index using db3 -  (-30974)
error: cannot open Packages database in /var/lib/rpm
CRITICAL:yum.main:

Error: rpmdb open failed

解决办法：rm -fr /var/lib/rpm/__db*