#
# A script to:
#  look at the pools in data protector
#  find any that have 'free' in their name
#  check the number of media in the pool
#  check the status of the tapes in the pool
#  output something that nagios can consume for monitoring
#  provide a nagios return code.  0=ok, 1=warning, 2=critical, 3=unknown
#
# Author: Derek Jones, CQUniversity Australia, Apr 2016
#
# Version: 1.0

$warning_limit  = 6;  # less than this many free tapes is just a warning, greater than or equal to this is OK
$critical_limit = 3;  # less than this many free tapes is BAD

if ( $critical_limit -ge $warning_limit )
{
  write-output "WARNING: critical limit is greater than warning limit... that makes no sense";
  exit(3);  # unknown state
}

# we want the output to show criticals first, then warnings... so we put out output into
# arrays, and print it all when we're finished
$criticals = @();
$warnings  = @();
$oks       = @();

# use the Data Protector omnimm command to list all of the pools
$output = cmd /c omnimm.exe -list_pool

# Loop over each line of the output
$line_number = 0;
foreach ( $line in $output.split("`r`n") )
{
  # skip the first 3 lines... they're just headers
  $line_number++;
  if ( $line_number -le 3 )
  {
    continue;
  }

  # skip any of our OLD pools
  if ( $line -like "*OLD*" )
  {
    continue;
  }

  # we only want any line with "free" written on it, because we're after free pools
  if ( $line -like "*free*" )
  {
    # break the line up into an array
    $fields = ($line -replace '\s+', ' ').split()

    # grab the name of the pool
    $pool   = $fields[1];

    # get detailed output about this pool... lists all tapes in the pool, their location and status
    $detailed_output = cmd /c omnimm.exe -list_pool "$pool" 2>&1

    $detail_line_number = 0;
    $tapes_in_this_pool = 0;

    if ( $detailed_output.length )
    {
      if ( $detailed_output -like "*No media configured in specified pool*" )
      {
        $tapes_in_this_pool = 0;
      }
      else
      {
        foreach ( $detail_line in $detailed_output.split("`r`n") )
        {
          # skip the first 3 lines... they're just headers
          $detail_line_number++;
          if ( $detail_line_number -le 3 )
          {
           continue;
          }

          # skip any tapes that aren't actually IN the physical tape library... we only care about tapes actually IN the library
          # because tapes in storage won't get used automatically, and we don't care if they're poor quality
          # from being 3 years old :)
          if ( -not ( ( $detail_line -like "*MSL-*" ) -or ( $detail_line -like "*VTL*" ) ) )
          {
            continue;
          }

          # line should start with "Good" if the tape is in good condition... otherwise, let us know
          if ( -not ( $detail_line -like "*Good*" ) )
          {
            # but we only care about physical tapes in poor condition
            if ( $detail_line -like "*MSL-*" )
            {
              $warnings+="$pool has a tape that won't get used";
            }

            continue;
          }

          $tapes_in_this_pool++;
        }
      }
    }

    # make sure the pool size is an integer
    if ( -not ( $tapes_in_this_pool -match "^[0-9]+$" ) )
    {
      write-output "Tape pool size '$tapes_in_this_pool' doesn't seem to be an integer";
      exit(3);  # unknown state
    }

    # is the number of free tapes in this pool a problem?
    if ( [int]$tapes_in_this_pool -le [int]$warning_limit )
    {
      if ( [int]$tapes_in_this_pool -le [int]$critical_limit )
      {
        # yep, this is bad
        $criticals+="$pool has $tapes_in_this_pool usable tapes (less than $critical_limit)";
      }
      else
      {
        # just a warning
        $warnings+="$pool has $tapes_in_this_pool usable tapes (less than $warning_limit)";
      }
    }
    else
    {
      $oks+="$pool has $tapes_in_this_pool usable tapes";
    }

  }
}
# That's the end of parsing the omnimm output.

# Now, and the all important nagios output.  If nagios sees the word "CRITICAL" then
# nagios will treat is as a critical, so we write those first.  Same for warnings.
# If all is well, we write OK

$returnState=3; # unknown

if ( $criticals.length )
{
  $string = $criticals -join ', ';
  "CRITICAL: " + $string;
  $returnState=2; #critical
}


if ( $warnings.length )
{
  $string = $warnings -join ', ';
  "WARNING: " + $string;
  if ( $returnState -eq 3 )
  {
    $returnState=1; # warning
  }
}


# if we didn't see any warnings or criticals, then all is well.  Show nagios an "OK" in the output
if ( -not ( $criticals.length -or $warnings.length ) )
{
  write-output "OK: Free pools size and free pools tape quality look good";
  if ( $returnState -eq 3 )
  {
    $returnState = 0;  # OK
  }
}

foreach ( $ok in $oks )
{
  write-output "$ok";
}

exit $returnState