Download needed package from official site and install it:
rpm -i --prefix=/opt/splunk splunk-6.1.3-220630-linux-2.6-x86_64.rpm
Add splunk executable to path:
# export SPLUNK_HOME=/opt/splunk/splunk
# export PATH=$SPLUNK_HOME/bin:$PATH
Acknowledge with licenses issue and after a couple of seconds installation will be finished.
Point your browser to http://localhost:8000 for Splunk web access.
Follow to machine which logs you want to collect and install splunk-forwarder there:
rpm -i --prefix=/opt/splunk-forwarder splunkforwarder-6.1.3-220630-linux-2.6-x86_64.rpm