To iterate what you've run;
# Remove Cloudera yum repo < see [1] how to install this
rm -vRf /etc/yum.repos.d/cloudera* /etc/cloudera-*
# remove Cloudera shared libraries, and all the cloudera yum cached packages files
# /var/lib/cloudera-scm-agent also contains the UUID [3] - so you might have also cleared this.
# what this effectively mean that once you re-install the agents packages the aget/host will not be associated with any clusters.
# we could fix this but you'll need you uuid from the database.
rm -vRf /usr/share/cmf /var/lib/cloudera* /var/cache/yum/cloudera*
# remove Cloudera logs
rm -vRf /var/log/cloudera-*
# Remove cloudera yum/rpm packages
yum remove cloudera*
# clean up various things which accumulate in the yum cache directory over time. More complete details can be found in the Clean Options section below.
yum clean all
> But I was trying to upgrade cloudera manager iteself. Unfortunetly after that I failed to install/upgrde cloudera agent in nodes.
Did you fail to upgrade Cloudera Manager Server and Agents?
What version of Cloudera Manager you are looking to upgrade to?
What is the value for your 'com.cloudera.cmf.db.type' in the /etc/cloudera-scm-server/db.properties file.
From the supplied information, you can still re-install Cloudera Manager following the installation instructions [1], and since you're behind proxy you could download [2] the .rpms and install them manually.
[1] http://www.cloudera.com/documentation/enterprise/latest/topics/cm_ig_install_path_b.html
[2] ie: RedHat 6 variant CM packages - http://archive.cloudera.com/cm5/redhat/6/x86_64/cm/5/RPMS/x86_64/
[3] Directory that store Cloudera Manager Agent state that persists across instances of the agent process and system reboots. The agent's UUID is stored here. Default: /var/lib/cloudera-scm-agent.
