how to setup cluster in Ejabberd

hi guys,

i will setup Ejabberd cluster in our Environment.pls tell the step by step installtion.
i also try with installtion guide.But it not helpless for us.

erl -sname ejabberd \
-mnesia dir '"/var/lib/ejabberd/"' \
-mnesia extra_db_nodes "['ejabberd@first']" \
-s mnesia

pls Explain this line: In this first is what.i execute this command in c:\Program Files\ejabberd-2.1.3\bin Directory.But it tell error.

pls help me any one.i am new to Ejabber.

thanks in advance

Regards,
moorthi