PMP> hrMIB Extensions and Top25 Corrections

PMP> hrMIB Extensions and Top25 Corrections

Tom Hastings hastings at cp10.es.xerox.com
Fri Oct 24 20:53:57 EDT 1997


Lloyd,


Our client developers agree that the problem is a problem and is worth
fixing.


Thanks,
Tom


At 04:45 10/23/1997 PDT, lpyoung at lexmark.com wrote:
>
>Harry,
>
>I would like to hear some feedback from people developing host printer
>management applications that are using the Printer MIB. Over the past
>month or so, we have had several host applications spring up that are
>using the Printer MIB for managing printers. Is this an area that is
>broken in the Printer MIB? If yes, does this change fix the problem?
>If we incorporate this change, will a host application developed
>against RFC 1759 still work correctly when run with a printer that
>has incorporated this change?
>
>Lloyd Young
>
>---------- Original note ---------
>
>
>
>
>harryl%us.ibm.com at interlock.lexmark.com
>10/22/97 07:21 PM
>
>
>To:   pmp%pwg.org at interlock.lexmark.com
>cc:    (bcc: Lloyd Young)
>bcc:  Lloyd Young
>Subject:  PMP> hrMIB Extensions and Top25 Corrections
>
>
>
>
>I recently made an observation regarding the mandated combination of
>OFFLINE with SERVICE REQUESTED in the "Top 25" alert table definitions.
>I don't think my point came across too clearly (as there has been little
>or no response). At the risk of being "lengthy", please let me attempt
>to clarify and make a proposal.
>BACKGROUND:
>----------
>1. RFC1759 utilizes a combination of status indications from the hrMIB,
>   including hrDeviceStatus, hrPrinterStatus and
>hrPrinterDetectedErrorState
>   to derive "Overall Printer Status" as defined in the table in section
>   2.2.13.2 (March 1995 version).
>2. Of all the "Overall Printer Status" definitions, only OFFLINE (and
>   moving offline) correspond directly with a specific
>   hrPrinterDetectedErrorState bit.
>3. The semantic of OFFLINE has never been adequately defined in the
>   printer MIB. Some devices do not incorporate the concept of
>ONLINE/OFFLINE.
>4. In it's definition of the hrPrinterDetectedErrorState, the hrMIB
>   (unfortunately) mandates correlation between the bits and hrDeviceStatus
>                  Condition         Bit #    hrDeviceStatus
>                    lowPaper          0        warning(3)
>                    noPaper           1        down(5)
>                    lowToner          2        warning(3)
>                    noToner           3        down(5)
>                    doorOpen          4        down(5)
>                    jammed            5        down(5)
>                    offline           6        down(5)
>                    serviceRequested  7        warning(3)
>   As such, there is no "No Paper Warning" as might occur when one tray
>   of n linked is exhausted, or no "Service Requested Down" as might
>   result from a fuser overheating.
>5. In conjunction with the development of the "Top 25" alerts, a
>   proposal was made to extend the hrPrinterDetectedErrorState bits
>   as follows
>
>               Condition          new hrBit         Today's mapping
>               ---------          ------            ---------------
>             inputTrayMissing        8            noPaper or lowPaper
>             outputTrayMissing       9            Service Requested
>             markerSupplyMissing    10            noToner
>             outputNearFull         11            Service Requested
>             outputFull             12            Service Requested
>
>PROBLEM:
>-------
>1. As it stands, the "Top 25" alerts resort to utilizing
>   uninformative, inappropriate or ambiguous combinations of
>   hrPrinterDetectedErrorState bits to overcome the constrained
>   associations described in 4 (above) or compensate for the
>   fact that proposal 5 (above) has received little or no
>   consideration by the keepers of the hrMIB.
>2. The areas in question are:
>   row  5 - Initial Power Up               - hrBit = offline
>   row  9 - Input Tray Missing (Critical)  - hrBit = noPaper
>   row 11 - Output Tray Missing (Critical) - hrBit = serviceRequested +
>offline
>   row 12 - Output Tray Full (Critical)    - hrBit = serviceRequested +
>offline
>   row 13 - Marker Supply Missing (Crit)   - hrBit = noToner
>   row 16 - Output Tray Almost Full (Warn) - hrBit = serviceRequested
>   row 18 - Input Tray Missing (warning)   - hrBit = lowPaper
>   row 19 - Input Tray Empty (warning)     - hrBit = lowPaper
>   row 20 - Output Tray Missing (warn)     - hrBit = serviceRequested
>   row 21 - Output Tray Full (warn)        - hrBit = serviceRequested
>3. OF THESE, ROWS 5,11 AND 12 ARE THE MOST SIGNIFICANT IN TERMS OF
>   MISLEADING INFORMATION, BECAUSE THEY MANDATE THE INDICATION OF
>   OFFLINE, A PRIMARY "OVERALL PRINTER STATUS", WHEN THE PRINTER
>   MAY NOT BE OFFLINE (AND, INDEED, SOME PRINTERS CANNOT GO OFFLINE).
>4. Rows 9,13,16,18,19,20 and 21, are "less than informative".
>
>PROPOSAL
>--------
>1. Acknowledge that it is beyond our control to see that the hrMIB will
>   ever be updated.
>2. Define a new OID in prtGeneral
> -- "prtDetectedErrors" hrMIB extension object.
> --
> -- This object extends the octet string originally defined in the
>    hrMIB (RFC1514) and is intended to operate in concert with the
>    hrMIB object hrPrinterDetectedErrorState. See Appendix E -
>    Overall Printer Status Table, for information on the use of
>    this object in conjunction with printer conditions and alerts."
> --
> -- Future extension of printer state "bits" will occur in this, printer
> -- MIB OID, not in the hrMIB.
>  prtDetectedErrors OBJECT-TYPE
>       SYNTAX OCTET STRING
>       ACCESS read-only
>       STATUS mandatory
>       DESCRIPTION
>               "This object represents additional error conditions
>               detected by the printer which were not included in
>               the initial hrMIB definitions or
>               hrPrinterDetectedErrorState. The error conditions
>               are encoded as bits in an octet string, with the
>               following definitions:
>                Condition           Bit #        hrDeviceStatus
>             inputTrayMissing         0        warning(3) or down(5)
>             outputTrayMissing        1        warning(3) or down(5)
>             markerSupplyMissing      2        warning(3) or down(5)
>             outputNearFull           3        warning(3) or down(5)
>             outputFull               4        warning(3) or down(5)
>             inputTrayEmpty           5        warning(3) or down(5)
>             Reserved                 6        n/a
>             Reserved                 7        n/a
>
>               If multiple conditions are currently detected and
>               the hrDeviceStatus would not otherwise be
>               unknown(1) or testing(4), the hrDeviceStatus shall
>               correspond to the worst state of those indicated,
>               where down(5) is worse than warning(3) which is
>               worse than running(2).
>               Bits are numbered starting with the most
>               significant bit of the first byte being bit 0, the
>               least significant bit of the first byte being bit
>               7, the most significant bit of the second byte
>               being bit 8, and so on.  A one bit encodes that
>               the condition was detected, while a zero bit
>               encodes that the condition was not detected.
>               This object is useful for alerting an operator to
>               specific warning or error conditions that may
>               occur, especially those requiring human
>               intervention.
>       ::= { prtGeneralEntry 20}
>3. Correct the "Top 25" table as follows:
>   row  5 - Initial Power Up               - hrBit = (0x0)
>   row  9 - Input Tray Missing (Critical)  - hrBit = inputTrayMissing
>   row 11 - Output Tray Missing (Critical) - hrBit = outputTrayMissing
>   row 12 - Output Tray Full (Critical)    - hrBit = outputFull
>   row 13 - Marker Supply Missing (Crit)   - hrBit = markerSupplyMissing
>   row 16 - Output Tray Almost Full (Warn) - hrBit = outputNearFull
>   row 18 - Input Tray Missing (warning)   - hrBit = inputTrayMissing
>   row 19 - Input Tray Empty (warning)     - hrBit = inputTrayEmpty
>   row 20 - Output Tray Missing (warn)     - hrBit = outputTrayMissing
>   row 21 - Output Tray Full (warn)        - hrBit = outputFull
>4. Define OFFLINE as follows and add this definition to the printer MIB
>   "The OFFLINE state may be implemented differently on various devices
>   and, indeed, some devices may not implement OFFLINE at all. In
>   general, if a device has an OFFLINE state it MUST indicate, via
>   hrPrinterDetectedErrorState bit (2) when this state has been entered
>
>
>
>
>
>



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