FAQ for the Printer MIB

The Printer MIB is the IETF proposed standard RFC1759. The protocol provided therein, provides a standard way for SNMP applications to identify a printer's attributes, and a printer's status.

Click Here to see RFC1759 and Click Here to see the mib version.

Besides some general cleanup and expanded object definitions, the newest version includes a couple of new variables. They include a printer serial number, a count of the number of critical errors that have been put in the alert table, the administratively assigned printer name, start-up and banner page control objects and manual feed and input tray switching objects.

The new version also includes additional possible values for many of the enumerations found within the specification. RFC1759 specifies that additional enums, called type 2 enums, may be used with RFC1759 compliant implementations after approval by the PMP. There are a number of additional enums that have been approved by the PMP since RFC1759 was published. Those additional enums are published in the latest draft. So if you want to describe the fuser in the supply table, you can use the enumeration for fuser in prtMarkerSuppliesType which has been included in the latest draft but was not in RFC1759, and still be compliant with RFC1759.

RFC1759 requires the interfaces group of RCF1213 - MIBII, and the device and storage groups of RFC1514 - HostResources MIB.

Each row in prtDevice will point to an entry in hrDevice where the OID of the row indicates the hrDevice to which the prtDevice row is referring. The value of the object PrtDeviceRefIndex is the printer device with which the hrDevice is associated. Clear as mud, right? Let's use a couple of examples to illustrate the point.

Let's deal with a simple case first. We shall define a single printer a disk, processor, serial port, parallel port and network interface. In this example, the disk device(device id 2) is associate with printer 1. Therefore prtDeviceRefIndex is sub-indexed with .2.1 where the .2 is the disk's device id and the .1 indicates that it is the first of the associations. Now the .1 could really start with any index but .1 is as good a starting point at any. The value of prtDeviceRefIndex is equal to 1 since the hrDeviceIndex of Printer 1 is 1.

In the slightly more complicated example, we shall add a second printer to the above case. The first printer shall have access to all of the devices except printer 2, but the second printer only has access to the disk, processor, and network interface. This does mean that the two printers are sharing the processor, disk and network interface. To help clarify the example, printer 1 is device 1 and printer two is device 7.

Look what happened to the entry for disk. The disk is now associated with both Printer 1 and Printer 2 which means that there are two entries in prtDevice for prtDeviceRefIndex.2. Additionally, Printer 1, Serial Port, Parallel Port and Printer 2 only have one entry in prtDevice.

A "door" is a physical cover that opens and closes and protects the physical contents of a device.

An "interlock" is a switch or sensor used to stop operation of a device when a necessary component for the proper operation of the device is missing.

It is safe to say that doors are interlocks but not all interlocks are doors.

The following is a list of some of the things that should cause the config change counter to be incremented:

hrDeviceID is a EOM specific product id and is defined as an object identifier. The "ProductOID" is constructed from the Vendor's number that was assigned by IANA plus a produt specific code. For example, IANA assigned EFI the number 2136, so the vendor number is 1.3.6.1.4.1.2136, and a product may be 1.3.6.1.4.1.2136.2 where the 2 identifies the product.

Full instructions for obtaining a Vendor number can be found at ftp://ftp.isi.edu/in-notes/iana/assignments/introduction

A duplexed page will have two impression on one sheet of paper.

http://www.bookcase.com/library/rfc/rfc-index-17xx.html - this will get you to RFC 1759.
http://www.simple-times.org/pub/simple-times/html/Printer-MIB.html - this will get you to the mib version RFC 1759.
http://www.bookcase.com/library/rfc/rfc-index-15xx.html - on this page is the Host Resources MIB, RFC 1514.
http://www.simple-times.org/pub/simple-times/html/HOST-RESOURCES-MIB.html - this will get you to the mib version RFC 1514.

mibwalk.PDF This is the MIB walk of the of the six printers.
alert.PDF This is the printer condition test.