No subscription, RH EL5 : Don't use it.
Use a free version of Redhat EL5 instead :
CentOS 5.5
http://www.centos.org/
EL 5 and CentOS 5.x are identical. ( No image of a red hat on CentOS.)
Another free one :
https://www.scientificlinux.org/
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P.S. : You can install software on RH EL, takes a lot of skill.
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