HP B5L29A Hard Disk

For Laserjet M604, M605, M606 Series Printers

Printers use hard disks largely to extend what they can hold in memory - especially if the power is turned off where RAM would not work. Printers can also use flash storage for this purpose but some print jobs can be a considerable size and might need a disk.

Multifunction printers often have a hard disk. The printer is essentially a multitasking computer and needs a disk or an euivalent SSD for much the same reason a computer does; it may be printing a job, receiving several others and scanning something else. store inbound material from the scanner - and from a fax line if there is one. All recent HP multifunction laser printers (such as the M630) have the option of a hard disk and many have one installed.

The M604 series printers can optionally have a hard-disk. All printers in the series have either:

  • a numeric keyboard, primarily so that users can give the printer a PIN before collecting their printout.
  • a touchpad screen which allows the machines menus and capabilities to do more such as saving and retrieving print jobs.
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Disks In Printers

A primary use for disks in printers is to store print jobs until the user is present, which is intended to improve document security.

A fly in the ointment of this approach has been disk security. Ordinarily when an operating system deletes a file it only removes the "inode" or file reference, it doesn't actually delete the data.

Other uses of a hard disk in a printer are to store things like forms, page layouts and standard letters. At one time it could make sense to store these in the printer because sending them across a serial link would be quite slow. With gigabit networking this need is lessened.

Things which are in the printer and only issued by it could be more secure than things that are generated by a PC and transmitted across the network. There are some clever tricks, such as issuing numbered and watermarked forms, certificates and tickets that can be verified as only produced by that printer. (You may know that colour printers produce a steganographic watermark anyway - a measure against counterfeiting). There is some security through obscurity in having things that only the printer can do.

Problems arise if the hard disk can fall into the wrong hands. In some older HP printers the disk is an EIO card held in with thumbscrews - removal takes a minute and since the printer functionality doesn't change much it might not be missed. The B5L29A is internal so not quite so accessible.

Another potential flaw is when the printer is sold. Again there is a risk the disk will be read.

To ensure security the disk needs to be encrypted so that it not work out of the printer and its contents are gibberish to anything but the printer. Disks are made secure by an exchange of digital keys between the printer and the disk or a control card fitted to the disk.

The disk should also not merely mark files as deleted but actively overwrite data blocks.

At the end of the printer's life on site the printer has a control panel, web-server and Web Jet-admin option to erase it. This should be used. The disk might be removed and destroyed but providing the HP deletion process has been done that bit of environmental vandalism is probably unnecessary.

The B5L29A fits inside the formatter enclosure over part of the formatter card.

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The hard disk plugs into the printer formatter; the master-processor which controls printer behaviour. I will be listed in the configuration page when it is correctly installed.

The disk is listed in the catalogue and on the accessories page .

A potential alternative to the hard disk would be the internal USB port board B5L28A together with a memory pen - but that has lower capacity and may lack the security features of the disk.

Another potential alternative is to use an external print-server or general purpose server with a disk. HP used to make an appliance that did this but dropped it from the catalogue some years ago. Apple and the Unixes have Michael Sweet's CUPS print subsystem.

Specifications

B5L29A Compatibility

  • HP Color LaserJet Enterprise M553n B5L24A
  • HP Color LaserJet Enterprise M553dn B5L25A
  • HP Color LaserJet Enterprise M553x B5L26A
  • HP Color LaserJet Enterprise M553dh B5L27A
  • HP Color LaserJet Managed M553dnm B5L38A
  • HP Color LaserJet Managed M553xm B5L39A
  • HP LaserJet Enterprise M604n E6B67A
  • HP LaserJet Enterprise M604dn E6B68A
  • HP LaserJet Enterprise M605n E6B69A
  • HP LaserJet Enterprise M605dn E6B70A
  • HP LaserJet Enterprise M605x E6B71A
  • HP LaserJet Enterprise M606dn E6B72A
  • HP LaserJet Enterprise M606x E6B73A
  • HP LaserJet Managed M605dnm L3U54A
  • HP LaserJet Managed M605xm L3U54A

Dimensions (W x D x H)

135.3 x 75.5 x 36.6 mm (5.4 x 3.0 x 1.4 in)

Package dimensions (W x D x H) 178 x 138 x 60 mm

Weight

109.9 g (0.24 lb)

Package weight 0.2 kg

Security

Remember to use the HP utilities to erase the disk when disposing of the printer

What's in the box

HP Secure High Performance Hard Disk Drive (FIPS 140-2 validated)

Installation guide

Supply Situation

The hard disk does not seem to be a very common option.

There were non in UK stock at the beginning of May 2015, they are probably ordered from HP European stock on demand.

Usually available for delivery in 5-7 days - our catalogue pages will reflect the situation.


Home Printers and Hard Disks

A bit of Web research suggests home printer users are quite often concerned that their printer might contain a hard disk. It would be very unusual for a home printer to contain any sort of disk - that sort of thing only becomes useful in the busy shared devices in offices. (One of our home printers does have a hard disk, but only because its an old office machine.)

It is possible to leave an SD card full of photographs forgotten in one of the memory slots on a printer. It is even more likely that will happen with a mobile phone. Printers have flash memory for their firmware but not usually for the data they print. With the majority of inkjets the page image is actually created in the computer and sent to the printer as a bitmap using a lightweight language anyway - so it wouldn't be practical to store much.

A notable exception is machines that can act as faxes; they might well store fax information in flash memory or more likely battery backed RAM. If the user guide suggests that fax memory can be held for 24 or 48 hours after a power cut then there is a potential security risk. There are thousands of designs, so only the specific manuals can answer such questions.