This might DWIM:

#!/your/perl/here
use strict;
use warnings;
my $last_line;
while (<>)
{
  if ( m/^Action:/ )
  {
    print $last_line;
  }
  $last_line = $_;
}
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Assuming you put this in file find_devices, and your input file is called new_elements, you would run it like this:

perl find_devices new_elements
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Please let us know if this works for you, or if it doesn't, why not.

Update:

For the rest of us, I've prefer this solution for newbies (having had a lot of interaction with some of them lately). There's no explicit open or close, there are only 2 variables mentioned (and only 1 needs to be declared), there's 1 while, 1 if, and 1 print. This could easily be a 1 liner:

perl -ne 'print $x if /^Action:/; $x=$_;' new_elements
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