Source Some packages are held by more than one repository. The priorities plugin choose packages from the highest-priority repository, excluding duplicate entries from other repos.
$ cat /etc/yum/pluginconf.d/priorities.conf enabled=0
$ yum erase yum-plugin-priorities
Listing excluded packages
$ yum list updates -d3
[Errno -3] Error performing checksum
Description: This happened on a CentOS 5 host when running YUM against a pulp-server on CentOS 6. Running
$ sudo yum makecachenever finished without this error message and running Puppet did not succeed either.
Solution: "What this really means that yum is too stupid to calculate the sha256 checksum correctly (and also too stupid to give you a sensible error message like "Sorry, primary.sqlite.bz2 is using a sha256 checksum, but I don't know how to calculate that")."
The fix is simple:
(client)$ sudo yum install python-hashlib
When running YUM against a pulp server, make sure the repository on a > CentOS 5.5 pulp server has been created with the right SHA setting (--checksum-type sha1)
[...] http://192.168.1.28/pulp/repos/centos/5.5/additions/x86_64/repodata/da0bfa72a4825e0134a6e0888396d00e0735294e6c52d76f58a2faa4b2c59615-primary.xml.gz: [Errno -3] Error performing checksum [...]
Show the last yum executions
$ yum history