[TriLUG] question about redhat-config-printer, lpd, and cups

[Lisa Lorenzin]

> Do note that redhat-config-printer GUI was only for LPRng in Red Hat
> Linux 7.3, but in RHL 9 it supports both.  (I can't remember what the
> status was in 8.0, but there's no real reason to use 8.0 anyway.)

yup.  i think the reason i started out assuming it supported both was that
we covered it in the rhce class (based on 9), and i didn't realize that
wasn't the case under 7.3 until i hit the redhat docs.

> I think in the above discussion you are using 'lpd' where you mean to
> say 'LPRng".  

yes.  symptomatic of my overall confusion between the two.

> I think this all comes from a misunderstanding of what the 'lpr, lpd'
> etc. programs do -- they're not part of LPRng only but refer to either
> LPRng or CUPS, depending on which is active.  Saying 'the default
> printer for lpd' and 'the default printer for CUPS' means the same thing
> because lpd is simply a symlink that points to the lpd compatibility
> binary that's part of the CUPS suite.

that helps a lot.  i had assumed, because the lprng daemon is named lpd in 
the init scripts, that lpd was specifically associated with lprng.  (the 
lpq man page supported that assumption, since it lists the history of 
LPRng.)

> > i figure that's just the way cups does things, and i'll learn more about
> > that as i get more familiar with cups.  but what does puzzle me is: if
> > redhat-config-printer-gui is only for use with lpd, then why does the
> > description field have "Created by redhat-config-printer 0.6.x" in it?  
> > since it was defined in cups, i don't understand why redhat-config-printer
> > would have anything to do with it.
> 
> Which configuration file?  /etc/printcap is edited by both systems, so
> it may end up with some comments like that that might not be perfectly
> accurate.

i don't know which configuration file - i can't figure out what config
files are front-ended by the webUI.  i'm finding cups to be fairly opaque
- there's no man/info page for it, and the webUI has limited information.

can you tell me which config files are used to generate the printer list
in the CUPS webUI?  i looked in the /etc/cups files, but none of them
contain that text in them, and printers.conf just has

# Printer configuration file for CUPS v1.1.14
# Written by cupsd on Tue 01 Jul 2003 05:25:05 PM GMT
<DefaultPrinter hp4l>
Info HP LaserJet 4L
Location Mike's Study
DeviceURI lpd://10.1.1.2/hp4l/
State Idle
Accepting Yes
JobSheets none none
QuotaPeriod 0
PageLimit 0
KLimit 0
</Printer>
<Printer hppsc2210>
Info HP PSC 2210
Location Lisa's Study
DeviceURI usb:/dev/usb/lp0
State Idle
Accepting Yes
JobSheets none none
QuotaPeriod 0
PageLimit 0
KLimit 0
</Printer>

but doesn't contain anything that would explain the entries for the 
hp4l-remote and hp4l at neo that show up in the printers list in the webUI.

> A word to the wise might be that if you're going to use CUPS (which many
> recommend) on RHL 7.3:
> 	* remove (rpm -e) the LPRng RPMs
> 	* remove (rpm -e) the redhat-config-printer RPMs, since it has no
> awareness of or support for CUPS
> 	* Install cups, run redhat-swithprinter to make sure CUPS is active
> 	* Administer CUPS via the web interface.

thanks for the advice!  unfortunately, i can't just remove LPRng entirely,
since that's how my access to the hp4l is working, and i'd like not to
have to give up a working printer in order to troubleshoot a non-working
one.  (my idea here is to run LPRng most of the time so i can print to the
hp4l, and just switch over to CUPS as needed to debug the psc2210 until i
get it working.  that way i don't get stuck with no print access from this
box.)

if i can get the hp4l working under CUPS, i *could* switch over and remove 
LPRng - i've just been focussed on the psc2210 so far because i do have 
a working config with the hp4l under LPRng.

						lisa

-- 
lisa lorenzin  |  lorenzin at 1000plus.com  |  http://www.1000plus.com/lisa/
of what avail is an open eye if the heart is blind? - solomon ibn gavirol