Problem installing rail_port


I am trying to install just the rails_port portion on my ubuntu machine and am following instructions given on
When I do rake db:migrate I get the following message

rake db:migrate
(in /home/mohamed/rubydev/misc/openstreetmap/rails_port)
== CreateCountries: migrating ================================================
– innodb_table()
→ 0.0001s
– create_table(:countries, {:force=>true, :Options=>“ENGINE=InnoDB”, :id=>false})
→ 0.0309s
– add_index(:countries, [:code], {:unique=>true, :name=>“countries_code_idx”})
→ 0.0104s
rake aborted!
An error has occurred, all later migrations canceled:

getaddrinfo: Name or service not known

(See full trace by running task with --trace)

Not sure why I am getting “getaddrinfo: Name or service not known”

Please advice…
Thanks in advance.