[1895] in Moira
Re: Towards Automatic Printer Driver Installation -- Printer Model Information
daemon@ATHENA.MIT.EDU (Garry Zacheiss)
Thu Nov 29 21:34:39 2001
Message-Id: <200111300234.VAA18355@brad-majors.mit.edu>
To: "Danilo Almeida" <dalmeida@MIT.EDU>
cc: moiradev@MIT.EDU
In-Reply-To: Your message of "Thu, 29 Nov 2001 15:06:46 EST."
<027101c17911$5f75dfd0$1b011212@mit.edu>
Date: Thu, 29 Nov 2001 21:34:25 -0500
From: Garry Zacheiss <zacheiss@MIT.EDU>
>> I would like to have accurate printer model information for the
>> printers in moira.
For the most part, we do.
>> I would like the printer model info to be accurate so that, given a
>> printer model info to system-specific driver name, I can install an
>> appropriate driver for the printer automatically.
Note that if you're going to do that, we'll need to export this
information someplace other than we do currently; your software
shouldn't be doing moira queries directly to find this information.
>> 1) Do we currently have such information or make any kind of effort
>> in this regard?
See above. Yes. There's a hwtype column in the printers table.
>> 2) Is moira indeed the right place for model information?
Model information is needed by the print filter software we use on
our print servers, so it's already there. We shouldn't keep duplicate
information elsewhere, since that will just make them get out of sync.
>> 3) Does the "hardware type" for a printer in moira get used for
>> anything?
Yes, it's exported into the printcap entry for the printer on the
print server, and used by ifhp (our filter) to determine what pjl the
printer supports, whether do use pjl or postscript for status queries,
etc. *Lots* of model specific information is encoded in ifhp.conf.
>> 4) What data is "hardware type" supposed to have?
The hardware type of the printer; Current types are lots of variants
on HP<foo> and LPR, indicating the printer pretends to be an lpd; almost
all of the latter are Apple Laserwriters.
>> 5) How is "hardware type" populated and updated? It is updated when
>> the printer is replaced?
By hand, when the printer is created. If a new type is needed, it's
added (although note that currently, adding a new type doesn't do
anything if it's not explictly listed in ifhp.conf). Yes, it is updated
when the printer is replaced.
>> 6) Do we have any queries/reports that list the different "hardware
>> type"s and number of printers of each type?
Yes, for the hardware types:
[zacheiss@frank-n-furter] ~$ qy -s gali printerhwtype TYPE \* | awk -F, '{print $3}'
HP
HP2100
HP4000
HP4500C
HP4M
HP4PLUS
HP4SI
HP4V
HP5000
HP5M
HP5MP
HP5SI
HP6MP
HP8000
HP8100
HP8500
HP8550MFP
HPCOLORLJ5M
HPDJ1600C
HPDJ890C
HPIIISI
LN03
LOCAL
LPR
SYSTEM
UNKNOWN
No, for the number of printers of each type. Adding a
"get_printer_by_hwtype" query would be easy, but doesn't seem
particularly useful.
>> 7) What issues do we need to consider in accomplishing the goal?
You should note that in some cases, printer specific drivers do more
harm than good, and there's no dishonor in falling back to a nice
generic postscript-only driver.
You should note that there are several cases in moira where a printer
is listed as just "HP" despite us knowing more specific information
about it. These are generally cases of the printer not performing the
way we would expect a printer of that model to behave, in which case we
use "HP" so it gets very general settings that should work on anything,
even if they aren't optimized for anything.
You should really note that printing tends to be one of our more
fragile services, and I'd much rather see you work with the current
state of the moira information than attempt to change it.
>> 8) Are there other (or alternate) lists that should be involved in
>> this discussion?
This most directly affects ops, as we maintain the print servers and
the current state of the moira printing software is there to support our
work; I think I can pretty effectively represent ops's interests.
Garry
