Last modified on $Date$ Before being able to use PyKota, you have of course to install it first. But before installing, you must carefully plan your installation. First you have to determine which machine will be the PyKota Storage Server. The Storage Server is the host responsible for keeping a centralized database of print usage for all your printers, users and groups. Then you have to list all the Print Servers for which you plan to use print quota facilities. Finally you have to download PyKota's latest version or buy an official package, from http://www.librelogiciel.com/software/. If you've just bought an official package, then as soon as you've receive it you have to decompress and visit its archive, to do so just type the following commands : jerome@nordine:~$ tar -zxf pykota-1.14_official.tar.gz jerome@nordine:~$ cd pykota-1.14_official jerome@nordine:~/pykota-1.14_official$ You can see many files in this directory, the first ones to read are README, then COPYING and LICENSE. They will give you basic installation instructions and explain the licensing terms under which PyKota is distributed. Of course they are also mostly boring to read ! Detailed installation and operating instructions are defined in the ./docs directory, in the form of SGML documentation in the DocBook format. You have to compile these files into readable documentation like the HTML or PDF formats, or buy an official PyKota package which already contains these compiled forms of the documentation. Now we will see what has to be done on each of the servers we are planning to use. Of course, depending on the size of your network, you may very well use the same machine as both a Print Server and a Storage Server. This is especially the case if you've got only one server. Depending on PyKota's version number, different types of storage backends may be supported, so we will see for each one of them how to configure it. PostgreSQL is an Object Relationnal DataBase Management System distributed under a Free Software license from the http://www.postgresql.org web site. It certainely is the free RDBMS which has the most advanced features, and is widely used all over the world. To configure your Storage Server, you must have PostgreSQL already working. The complete installation of PostgreSQL is not covered by the present manual, please refer to your system's documentation or to http://www.postgresql.org for details. One thing you have to check, though, is that every Print Server on which you want to install the print quota mechanism, must be able to connect to the PostgreSQL server. In the default installation of PostgreSQL this may not be the case for security reasons, except if both servers are in fact the same machine. In any case, it is recommended that you check the /etc/postgresql/pg_hba.conf file and modify it if needed. This file is self documented and its modification is straightforward. You also have to make sure that PostgreSQL accepts TCP/IP connections. To do so you either have to launch it with the -i option or modify the /etc/postgresql/postgresql.conf file, which is self documented and easy to modify too. Don't forget to restart PostgreSQL if you modify any of its configuration files, in order for the changes to take effect. Be careful, you may be unable to connect from a Print Server to the PostgreSQL server even if the configuration is correct. Sometimes your connections may be blocked by one or more network firewalls along the route from one machine to the other. If this is the case, then the best thing you can do is to ask your Network Administrator to not filter the IP port used by PostgreSQL, which is usually port 5432/tcp. The TCP/IP network port used by PostgreSQL may be different. When in doubt, ask your System Administrator for the correct value. Now that your PostgreSQL server is up and running, and is waiting for your connections, you have to create the Quota Storage DataBase. To do so, you'll have to feed PostgreSQL with the pykota-x.xx/initscripts/postgresql/pykota-postgresql.sql file. This file will create a Quota DataBase administrator in the PostgreSQL system, then create an empty Quota DataBase and set some permissions on it. The Quota DataBase administrator is the PostgreSQL's user used to manage the Quota database. The Quota DataBase Administrator is not present in the Quota Database itself, he is only defined in PostgreSQL and don't have to exist on any system, nor in the Quota DataBase. His default names is pykotaadmin. A Quota Storage read-only user is also created under the name of pykotauser. This read-only user is used by PyKota to connect to the Quota Storage when a non-root user launches a pykota command. This prevents normal users from being able to modify their own, or other users', quota information. The database which will be created will be named pykota by default. You can choose other names if you want, just modify the initscripts/postgresql/pykota-postgresql.sql file accordingly, and report your changes into PyKota's configuration file. To run this script, you can use the psql frontend to PostgreSQL, but your priviledges must be sufficient to be allowed to create users and databases. You can launch psql as the postgres user which is PostgreSQL's default administrator, and connect to the default database named template1. From a command line interpreter (i.e. shell), type the following commands : jerome@nordine:~$ cd pykota-1.14_official/initscripts/postgresql jerome@nordine:~/pykota-1.14_official/initscripts$ psql -h localhost -U postgres template1 Welcome to psql, the PostgreSQL interactive terminal. Type: \copyright for distribution terms \h for help with SQL commands \? for help on internal slash commands \g or terminate with semicolon to execute query \q to quit template1=# \i pykota-postgresql.sql ... a lot of output lines pykota=# For security reasons, you may want to set passwords in PostgreSQL for the pykotaadmin and pykotauser users. Otherwise any user able to connect to PostgreSQL on your Quota Storage Server could connect to the quota database, and either see it, or even modify it without problem. To do so, just type the following lines while still being at the psql prompt (replace the password values by your own, and do the same for the pykotauser user) : pykota=# ALTER USER pykotaadmin PASSWORD 'somepassword'; ALTER USER pykota=# \q jerome@nordine:~/pykota-1.14_official/initscripts/postgresql$ The \q command above will quit the psql program and return you to the shell's command line prompt. To improve security further, you could encrypt your database connections, or take any other step as needed. Please refer to PostgreSQL's documentation for details. Also if PyKota's configuration file /etc/pykota/pykotadmin.conf is readable by anyone with access on your file system, a local user could create some script to modify his own print quota. Defining passwords may not be sufficient if your database access rule is set to trust in the /etc/postgresql/pg_hba.conf. Again, please refer to PostgreSQL's documentation for details. Also, passwords will fly unencrypted over the network by default, so be sure to take any necessary step to secure your database server from unauthorized use. This has nothing to do with PyKota though, it is just a general rule to keep in mind. If no error occured, then your Quota DataBase is ready to be used. Now you can let the Quota Storage Server alone, the remaining work will have to be done on each one of the print servers which will use this particular Quota Storage Server. If an error occured, maybe your PostgreSQL version is too old, or an unexpected problem (like a bug) happened. Please send me an email so that I can try to solve the problem. Thanks in advance. From version 1.09 on, OpenLDAP can be used as a Quota Storage Backend. It is possible that other LDAP servers can be used, but this is currently untested. To use OpenLDAP as your Quota Storage Backend, you have to copy the pykota/initscripts/ldap/pykota.schema in OpenLDAP's schemas directory. Under Debian GNU/Linux, this is something like : $ cp pykota.schema /etc/ldap/schema Then edit /etc/ldap/slapd.conf and add a line to include the PyKota schema. You should have something like : # Schema and objectClass definitions include /etc/ldap/schema/core.schema include /etc/ldap/schema/cosine.schema include /etc/ldap/schema/nis.schema include /etc/ldap/schema/inetorgperson.schema include /etc/ldap/schema/pykota.schema Finally, restart the OpenLDAP server : $ /etc/init.d/slapd restart Then you have to modify PyKota's configuration files /etc/pykota/pykota.conf and /etc/pykota/pykotadmin.conf to include LDAP specific options. You may want to give a look at pykota/conf/pykota.conf.sample to see all the options that are needed. Adapt the values to your own configuration, and finally initialize your Quota Storage with the help of the edpykota command. A MySQL Storage Backend is planned, but it actually doesn't exist. A Berkeley DB Storage Backend is planned, but it actually doesn't exist. It seems that remote storage won't be possible with such a backend, so in other terms this means that you will have a different quota database on each print server. This may still prove to be useful for small configurations. For each Print Server on which you plan to implement the print quota mechanism, you have, of course, to have an already working printing environment. Currently PyKota works with either the CUPS or the LPRng, but more may be added in the future. Here's the list of software you have to install on each Print Server, version numbers are given as an indication of which was successfully tested, but older versions may work too. CUPS version 1.1 or above, or LPRng version 3.8.20 or above (it probably works with older versions but this is untested). You can download them from http://www.cups.org or http://lprng.sourceforge.net Python version 2.1 or above. You can download it from http://www.python.org. Quota Storage client libraries, depending on your Quota Storage Backend : PostgreSQL backend : PostgreSQL client libraries. They must match the PostgreSQL version used on your Quota Storage Server. The PygreSQL python module. It must match the PostgreSQL client libraries' version, as well as Python's version. LDAP backend : TODO MySQL backend : TODO Berkeley DB backend : TODO ucd-snmp or net-snmp tools, version 4.2.5 or above. You only need the snmpget command. You can download them from http://www.sourceforge.net/projects/net-snmp/. You only need this if you plan to query your printers for their internal page counter via SNMP. netatalk version 1.6.1 or above. You only need the pap command. You can download them from http://netatalk.sourceforge.net/. You only need this if you plan to query your printers for their internal page counter via AppleTalk. eGenix' mxDateTime Python module version 2.0.3 or above. It must match your default Python version. You can download it from http://www.egenix.com.