A puppet function to try to programmatically monitor smart disks

smartd_guess.rb

  newfunction(:smartd_guess, :type => :rvalue, :doc =>
    'smartd_guess tries to guess which block devices are available for smart 
monitoring, and which should be ignored.

It iterates through the $::blockdevices fact, and returns an ARRAY of HASHES
compatible with the jhoblitt smartd module:
https://github.com/jhoblitt/puppet-smartd#devices

This function exists because smartd AUTOSCAN is too dumb, and manually 
specifying smartd configs on a per server basis is not web-scale.

') do |args|

    devices_guess = []
    # We start smart tests at 2AM
    hour_counter=2
    for device in lookupvar('blockdevices').split(",").sort() do
      next if not device.match('^sd')

      # According to the smartd.conf man page, HOUR must be double digit, 00-23
      hour = '%02d' % hour_counter
      smartd_device_hash = { 'device' => "/dev/#{device}" }
      vendor = lookupvar("blockdevice_#{device}_vendor")
      case vendor
      when 'ATA'
        # Ata devices need smart on. ATA really implies sat now that we are in 2013?
        smartd_device_hash['options']="-a -d sat -s (S/../../[1-6]/#{hour}|L/../../7/#{hour})"
      when 'SEAGATE', 'FUJITSU'
        # When a device has a vendor name directly, it means it is being 
        # identified via SCSI
        smartd_device_hash['options']="-d scsi -s (S/../../[1-6]/#{hour}|L/../../7/#{hour})"
      when 'SMC'
        # This is an SMC device. TODO: Enumerate through SMC drives
        smartd_device_hash['options']="-d ignore"
      when 'LSI', 'LSILOGIC'
        # This is an LSI raid device. TODO: Enumerate through LSI drives
        smartd_device_hash['options']="-d ignore"
      when 'Adaptec'
        # This is an adaptec raid device. TODO: Enumerate through adaptec drives
        smartd_device_hash['options']="-d ignore"
      when 'AMCC'
        # This is the 3ware vendor. TODO: Enumerate through 3ware drives
        smartd_device_hash['options']="-d ignore"
      when 'HP'
        # This is the HP vendor. TODO: Enumerate through HP drives
        smartd_device_hash['options']="-d ignore"
      else
        # If there is a devices that is not covered above, then we are 
        # not ready to intrepret it
        raise Puppet::ParseError, "Device #{device} has a vendor #{vendor} which 
is unknown to smartd_guess(). Please tell someone in OPS. If this drive is 
monitorable, we want to account for it."
      end #end vendor case
      # We are building an array of hashes, one hash per disk
      devices_guess += [ smartd_device_hash ]
      hour_counter += 1

    end # end device loop
    return devices_guess

  end # end function
end # end module