ask net-ping

Your array is a simple array, but you're referencing it like its an
array of hashes.

Also you're using I like an incrementor, but you never increment it.
Its not very ruby-like.

Try this:

@arr_stat = Node.all.map do |node|
{:ipadd => node.ipadd, :status =>
PingExternal.new(node.ipadd) ? "online" : "offline"}
end

However, depending on what you want to do with this data later, this
may be a bad implentation.

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