yum: no dbpath has been set

# yum clean all
Loaded plugins: fastestmirror
rpmdb: unable to join the environment
error: db4 error(11) from dbenv->open: Resource temporarily unavailable
error: cannot open Packages index using db3 - Resource temporarily unavailable (11)
error: cannot open Packages database in /var/lib/rpm
Traceback (most recent call last):
File "/usr/bin/yum", line 29, in ?
yummain.user_main(sys.argv[1:], exit_code=True)
File "/usr/share/yum-cli/yummain.py", line 309, in user_main
errcode = main(args)
File "/usr/share/yum-cli/yummain.py", line 157, in main
base.getOptionsConfig(args)
File "/usr/share/yum-cli/cli.py", line 187, in getOptionsConfig
self.conf
File "/usr/lib/python2.4/site-packages/yum/__init__.py", line 664, in
conf = property(fget=lambda self: self._getConfig(),
File "/usr/lib/python2.4/site-packages/yum/__init__.py", line 239, in _getConfig
self._conf = config.readMainConfig(startupconf)
File "/usr/lib/python2.4/site-packages/yum/config.py", line 804, in readMainConfig
yumvars['releasever'] = _getsysver(startupconf.installroot, startupconf.distroverpkg)
File "/usr/lib/python2.4/site-packages/yum/config.py", line 877, in _getsysver
idx = ts.dbMatch('provides', distroverpkg)

При yum update тоже самое

# yum update
Loaded plugins: fastestmirror
error: no dbpath has been set
error: cannot open Packages database in /%{_dbpath}
Traceback (most recent call last):

Как фиксится:

#yum clean all
#rm -f /var/lib/rpm/__db*
#rpm --rebuilddb
#yum update

Но перед этим крайне советую проверить количество оставшейся свободной памяти на диске, такая ощибка может возникать при переполнении диска и нехватке свободного места.