The configurator is a set of Python scripts and classes that keep track of various bits and pieces of information on all of our machines. This way, configuration files can be easily autogenerated.

Basics

The configuration consists of two python classes, UGCSHost and UGSCClass, in UgcsComputers. Each host is represented by a UGCSHost, and can have information set on it. It also may belong to several UGCSClasses. If a script requests some information from a host that it does not have, the host __getattr__ method will look through the classes in an attempt to find it. This way, you can set one piece of information for all hosts in a class easily (example: the 'shellsever' class has the property vlan='ugcs-shell', so any computer that belongs to that class has the property vlan='ugcs-shell' ) The list of classes, hosts, etc is saved in a python pickle dump in /afs/ugcs/ugcs-admin/configurator/machines.pck

UgcsComputers module documentation

UGCSHost

Properties

• ip
• mac
• name

UGCSClass

• UGCSClass(classname, priority)

Methods

• load()
• save()
• add_host(host_instance)
• get_host(hostname)
• get_hosts
• remove_host(hostname)
• rename_host(from, to)
• get_class(classname)
• get_classes
• add_class(class_instance)

How to use

To edit the configuration, start up python in /afs/ugcs/ugcs-admin/configurator and:

from UgcsComputers import * # Load everything we need and some helpers
load() # Read in machines.pck
# Do stuff here
save() # Save the changes

Stuff may include some of the following:

• to be done

Configuration scripts

None of the configuration scripts currently overwrite any files; you must pipe them to the file (or use <script> | sudo tee file) if you want them to actually do something.

create_vmps_db.py

Creates the vmps db for charon. This is typically run on charon; you must scp machines.pck to root@charon:/root/, ssh into charon, and run /root/create_vmps_db.py . It adds all the computers in the classes coreserver, shellserver, and hosted.

generate-demeter-exports.py

Creates the autogenerated part of /etc/exports on demeter. It add /etc/exports.input at the end for static exports. It uses machines from the classes puke-ro and puke-rw, and gets nfs mount information from <host>.nfsmouts, which should be a list of tuples (export, params). If export contains '%s', it is replace with the machine name (just once). Params should typically include ro or rw, no_subtree_check, and no_root_squash.

generate_bind_db.py, generate_bind_rdns.py

These two generate db.ugcs.caltech.edu and db.176.215.131 for bind on demeter. Both use all the hosts and do not care about classes. generate_bind_rdns.py looks for all ips, and if one doesn't exist, substitutes addr-<tail> for the rdns name. generate_bind_db.py uses the classes coreserver, shellserver, and hosted. If a host has extra_dns set, the contents of extra_dns (either a string or a list) will be added after the A record. generate_bind_db.py also looks in /etc/bind/db.ugcs.caltech.edu.input for static stuff (CNAMES,etc), but outputs the header itself.