rpmdb: Program version 4.3 doesn’t match environment version

Este problema puede ocasionarse en servidores con Centos 4.3 o 4.6 al actualizar paquetes :

# yum clean
rpmdb: Program version 4.3 doesn't match environment version
error: db4 error(-30974) from dbenv->open: DB_VERSION_MISMATCH: Database environment version mismatch
error: cannot open Packages index using db3 -  (-30974)
error: cannot open Packages database in /var/lib/rpm
Traceback (most recent call last):
  File "/usr/bin/yum", line 29, in ?
    yummain.main(sys.argv[1:])
  File "/usr/share/yum-cli/yummain.py", line 80, in main
    base.getOptionsConfig(args)
  File "/usr/share/yum-cli/cli.py", line 170, in getOptionsConfig
    self.doConfigSetup(fn=opts.conffile, root=root)
  File "__init__.py", line 82, in doConfigSetup
  File "config.py", line 273, in __init__
  File "config.py", line 385, in _getsysver
TypeError: rpmdb open failed

Para solucionarno hay que recrear la base de datos de paquetes :

# rm -f /var/lib/rpm/__db.*
# rpm --rebuilddb