gistfile1.txt

this_time = Time.new

ruby_block 'Update sshd_config' do
  block do
    begin
      file = Chef::Util::FileEdit.new('/etc/ssh/sshd_config')
    rescue StandardError => e
      puts "==>### ERROR: #{e.message}"
    end
    file.search_file_replace_line(/#?GSSAPIAuthentication yes/, "GSSAPIAuthentication no #Updated by Chef #{this_time.inspect}")
    file.search_file_replace_line(/#?UseDNS yes/, "UseDNS no #Updated by Chef #{this_time.inspect}")
    if file.unwritten_changes?
      file.write_file
      notifies :restart, 'service[sshd]', :immediately
    end
  end
end

service 'sshd' do
  action :nothing
end

Thank you. In some case (some version of Chef?), we need to do this:

notifies :restart, resources(:service => "sshd"), :immediately
instead of

notifies :restart, 'service[sshd]', :immediately