Synnefo

README.admin - Administration notes

This file contains notes related to administration of a working Synnefo

deployment. This document should be read *after* README.deploy, which contains

step-by-step Synnefo deployment instructions.

Database

========

MySQL: manage.py dbshell seems to ignore the setting of 'init_command'

       in settings.DATABASES

Reconciliation mechanism

========================

On certain occasions, such as a Ganeti or RabbitMQ failure, the VM state in the

system's database may differ from that in the Ganeti installation. The

reconciliation process is designed to bring the system's database in sync with

what Ganeti knows about each VM, and is able to detect the following three

conditions:

 * Stale DB servers without corresponding Ganeti instances

 * Orphan Ganeti instances, without corresponding DB entries

 * Out-of-sync operstate for DB entries wrt to Ganeti instances

The reconciliation mechanism runs as a management command, e.g., as follows:

[PYTHONPATH needs to contain the parent of the synnefo Django project

directory]:

/srv/synnefo$ export PYTHONPATH=/srv:$PYTHONPATH

vkoukis@dev67:~/synnefo [reconc]$ ./manage.py reconcile --detect-all -v 2

Please see ./manage.py reconcile --help for all the details.

The administrator can also trigger reconciliation of operating state manually,

by issuing a Ganeti OP_INSTANCE_QUERY_DATA command on a Synnefo VM, using

gnt-instance info.

Logging

=======

Logging in Synnefo is using Python's logging module. The module is configured

using a configuration file, whose format is described here:

http://docs.python.org/library/logging.config.html

By default, the log initialization code will look for the logging.conf file

in the following locations in order:

1. /etc/synnefo/logging.conf

2. os.getcwd()/logging.conf

3. synnefo.logic.__path__[0]/logging.conf (<-- this is the default)

The default configuration is using Linux conventions: it logs to /dev/log for

all loggers. The default configuration can be changed by copying the default

file to any of the above mentioned locations and changing it appropriately.

* Logging and demonization: If the logging is configured to print to the console

  (using the consoleHandler handler) then daemon processes (notably, the

  dispatcher) will not work as it should. This only happens after the daemon

  has lost its controlling terminal (e.g. because the terminal was closed);

  in this case the dispatcher does not know where to log to and depending on

  the system it either crashes or stalls. This can be avoided if the logging

  module is not configured to output to the console.

Admin Tools

===========

snf-admin is a tool used to perform various administrative tasks. It needs to

be able to access the django database, so the following should be able to import

the Django settings.

Additionally, administrative tasks can be performed via the admin web interface

located in /admin. Only users of type ADMIN can access the admin pages. To change

the type of a user to ADMIN, snf-admin can be used:

   snf-admin user modify 42 --type ADMIN