centos系统使用yum命令安装软件包时候报错：
error: rpmdb: BDB0113 Thread/process 2229/140657048729600 failed: BDB1507 Thread died in Berkeley DB library
error: db5 error(-30973) from dbenv->failchk: BDB0087 DB_RUNRECOVERY: Fatal error, run database recovery
error: cannot open Packages index using db5 - (-30973)
error: cannot open Packages database in /var/lib/rpm
CRITICAL:yum.main:
Error: rpmdb open failed
原因是RPM数据库被破坏，重建数据库后恢复正常：
cd /var/lib/rpm/
for i in `ls | grep 'db.'`;do mv $i $i.bak;done
rpm --rebuilddb
yum clean all
