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1PyKota's FAQ :
3  # $Id$
5  * How can I diagnose the problem when something goes wrong ?
7    Put "LogLevel debug2" in cupsd.conf (usually in /etc/cups/).
8    Then put "logger: stderr", "debug: yes" and
9    "crashrecipient: youremailaddress" in /etc/pykota/pykota.conf.
10    Finally restart CUPS.
11    CUPS' error_log file will now contain many informations which
12    will help diagnose your problem. You will receive failure
13    notices by email, and you can send all this to us for
14    diagnostic. Please send complete files and not some sparse
15    parts of them. Also please send the log files as gzipped
16    (or bzip2-ed) attachments.
18    For LPRng, better to put "logger: system" in pykota.conf so
19    that all debug messages for PyKota will go to syslog's
20    destination for the LPR syslog facility.
22    IMPORTANT : please don't send log files to the mailing list
23    unless they are very small of unless someone asked for this.
25  * Some commands tell me I'm not allowed to use them, why ?
27    Some commands refuse to work when launched as a normal user,
28    and output a message saying "You're not allowed to use this
29    command." This is because their use is reserved to PyKota
30    Administrators. A PyKota Administrator is any user allowed
31    to read the pykotadmin.conf file. Beware : any user who can
32    read this file can connect to PyKota's database in read+write
33    mode, so take care of not opening a breach when modifying
34    the permissions on this file.
36  * What permissions should I use on PyKota's configuration files ?   
38    It's probably best to do this :
40        $ chown pykota.pykota pykota.conf pykotadmin.conf
41        $ chmod 640 pykota.conf
42        $ chmod 600 pykotadmin.conf
44    Then the user 'pykota' will be the only PyKota Administrator   
45    (with user 'root' of course), but all members of the 'pykota'
46    group will be allowed to use unrestricted PyKota commands
47    like repykota.
49  * How can I limit my users to N pages per day (month/year) ?
51    The easiest way to do this is to create their print quota
52    entries using something like :
54      $ edpykota --add -S 30 -H 30 user1 user2 user3 ...
56      this would limit users to 30 pages on each printer.
58    Then in a crontab launched every day (month/year) you could   
59    do :
61      00 23 * * * /usr/bin/edpykota --reset
63      this would reset every user's page counter to 0 on each printer
64      at 23h00 every day.
66  * How can I tell PyKota to allow some users to print without limitation ?
68    Just create these users' print quota entries this way :
70      $ edpykota --add --limitby quota --noquota user1 user2 ...
72      This would effectively put these users in "no limit" mode on
73      each printer. If you want to do this only on some printers, just
74      use the --printer command line argument as well. See
75      edpykota's documentation for details.
77    Another way to do this when you limit your users by balance, is 
78    to set an overcharging factor of zero for every user you want to
79    print with no limitation :
81      $ edpykota --add --limitby balance --overcharge 0 user1 user2 ...
83  * Nothing prints when my printer is in PowerSave mode, what
84    can I do ?
86    This happens if you use hardware accounting with SNMP, because
87    some (all ?) printers don't say they are idle when they are
88    in PowerSave mode.
89    For now your best bet is to disable PowerSave mode in
90    your printer. In the future, PyKota will modified to
91    handle such problems.
93  * I've installed all correctly, I've created users
94    and printers, but when printing nothing works.
95    What is the problem ?
96    The most probable cause for this is that you didn't
97    adapt /etc/pykota/pykota.conf to your own configuration.
98    The file installed by default is just an example, you
99    have to modify it. See the rest of this document to
100    learn how to really diagnose what went wrong.
102  * I've downloaded PyKota from CVS using a Windows based CVS 
103    tool, and now nothing works at all. What happened ?
105    Some (all?) Windows based CVS tools translate *nix line endings
106    (character Line Feed, ASCII code 10) into Windows line endings
107    (character Carriage Return, ASCII code 13, followed with
108    character Line Feed). This breaks the software which has
109    to run under *nix compatible systems. Set correct options
110    in your CVS software so that it doesn't do any translation,
111    or use an Unix-like version of CVS, download again and
112    reinstall the software. It should work.
114  * Why doesn't CUPS under Debian Woody automatically
115    detects PyKota managed devices ?
117    The CUPS version in Debian Woody is 1.1.14 which is a bit
118    too old. To use PyKota with this version, just install
119    your printers as usual in CUPS web interface, and ensure
120    they work fine, then save your changes, and modify
121    /etc/cups/printers.conf manually as explained in
122    PyKota's toplevel README file. Finally restart CUPS,
123    and your printers should be managed by PyKota.
124    Another solution is to install a newer CUPS release.
126  * Is print accounting ever exact ?
128    No. Print accounting is **never** exact, because it depends
129    on external factors like the presence of paper in the printer,
130    the quantity of remaining ink in the print cartridge, paper
131    jams, etc... All these things are very difficult to account
132    for correctly, and no print accounting package deals with
133    these artefacts correctly in all situations.
134    We are however confident that PyKota is one of the more
135    exact print accounting software, because by default it
136    asks the printers for how many pages they have really printed.
138  * Can PyKota account for ink usage ? 
140    No. Actually PyKota doesn't account for ink usage, but this
141    may come in a future release. PyKota only accounts for pages
142    printed and/or money spent.  If ink accounting is a necessity
143    for you, PrintBill is recommended instead of PyKota. PrintBill
144    allows you to bill differently per color, and to bill depending
145    on the percent of the ink covered part of the pages.
147  * What is a 'dumb printer' ?
149    In PyKota, the term 'dumb printer' defines a printer which doesn't
150    natively understand PostScript, PCL5 (up to), PCLXL (aka PCL6), PDF
151    or ESC/P2 and doesn't have an internal page counter, and for which
152    you don't know how to compute a job's size in number of pages by
153    analyzing its content.
154    Any printer which is not a 'dumb printer' according to the above
155    definition is supported by PyKota.
157  * How can I make PyKota work with my non-postscript printer under
158    CUPS ? 
160    From version 1.16alpha7, PyKota includes a CUPS backend which
161    allows you to use any type of printer and any driver, provided
162    your printer is not a 'dumb printer' (see above).
164  * How can I use my 'dumb printer' with CUPS and PyKota. 
166    You have to use a software accounter directive, and
167    create a script which understands your printer's
168    Page Description Language.
170    PyKota natively understands DSC compliant PostScript,
171    PCL3, PCL4, PCL5, PCLXL (aka PCL6), PDF and ESC/P2. Support
172    for Binary PostScript is done through GhostScript. More PDLs
173    will be added in the future. 
174    However you can always plug your own PDL analyzer in PyKota.
176  * I've got a great number of users. How can I automatically
177    set an initial print quota for them on first print ?
179    You have to define an external policy for unknown users,
180    to automatically add them to the Print Quota database.
181    The sample configuration file contains examples to do this.
183  * What does the --prototype command line option to edpykota do ?
185    This option allows you to use an existing user or group
186    as a template when creating or modifying other accounts.
188  * How can I share print quota between some printers only (not all) ?   
190    To do this you have to put the printers into a printers group, and
191    set quota on the printer group, instead of (or in addition to)
192    the printers themselves.
194  * What is a printer group ?
196     A printer group is exactly like a normal printer, but is
197     unknown by the printing system. You can use printer groups
198     to share print quota between printers.
200  * How can I create a printer group ?   
202    Just use pkprinters, like for normal printers, then create
203    quota entries for users or users groups on it using the
204    edpykota command
206  * How can I put a printer into a printer group ?
208    Use the pkprinters command to do this.
210      $ pkprinters --help
212    Will print the complete help and tell you how to do.
214  * How quota checking and update is done with printer groups ?   
216    Print accounting and quota checking is done for a printer and
217    all the printers groups it belongs to, recursively.
218    If quota is reached on ANY of these printers for the current user,
219    printing is denied.
221  * Is this feature robust ?
223    It should be. However, beware of integrity problems. LDAP has no
224    sense of database integrity, and PostgreSQL constraints have not
225    yet been fully implemented. The code actually *tries* to forbid
226    circular printers groups, but if you create printer groups with
227    another tool (e.g. psql or gq), then you are mostly on you
228    own to not create infinite loops.
230  * How is computed the job's price ? 
232    A job's price is computed with this formula :
234      SUM((NbPages * PricePerPage) + PricePerJob)
236    For current printer and all the printers groups it is
237    a member of, if any, recursively.
238    This may be difficult to grasp, but offers unprecedented
239    flexibility.
241  * My question isn't answered there, can you help ? 
243    Sure. Ask your question to the mailing list. If this is a
244    frequently asked question, or if your problem is on the contrary
245    very specific, it will probably be added to this document.
247    You can also ask questions by IRC :
249        /server
250        /join #pykota
252Send any new questions to Jerome Alet - <>
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