Short description of Evidence control system

This directory contains the backbone of the control system.

Config is the configuration server and needs to run before any other DIM
server that requests configuration information is started (if a configuration
request cannot be answered, a server will normally not start). A configuration
file can be given on the command line.

DColl is the central data collector. It subscribes to all services handled by
the name server and writes them to disk (except those excluded in the
configuration file). It also provides a history service for all DIM services
and a command for logging.

Alarm can be configured to check all servers for availability and status and
can produce a master alarm.

The DIMDIR environment variable needs to point to the DIM installation directory
when compiling. DIM_DNS_NODE must point to the name server for any DIM server
to run.

- Oliver Grimm, 18/1/2010

Version history
---------------

19/5/2010	Service histories now available via DimRpc from DColl, not via .hist service
			When regular expression compiling results in error, State is set to ERROR, not
			FATAL. The erroneous expression is ignored in the following.
25/5/2010	Service history remains available if service itself become unavailable. If not
			yet in memory, reading from history file is tried. Improved error handling of
			history files.
28/5/2010	Changed name of 'State' service to 'Message' to better reflect its functionality.
			Added client information to log file entries.			
30/5/2010	Created Bridge server that repeats services from one DNS to another.
			Service quality now also written to slow data file.
31/5/2010	Configuration file format now follows semi-standard INI format.
7/6/2010	Separated History service from DColl. History format changed, now includes
			service format (allows history access also when service is unavailable).


Preliminary firewall settings on eth-vme02 (rule 5 for DIM, rule 6 for X11 over ssh)

Chain INPUT (policy ACCEPT)
num  target     prot opt source               destination
1    RH-Firewall-1-INPUT  all  --  0.0.0.0/0            0.0.0.0/0

Chain FORWARD (policy ACCEPT)
num  target     prot opt source               destination
1    RH-Firewall-1-INPUT  all  --  0.0.0.0/0            0.0.0.0/0

Chain OUTPUT (policy ACCEPT)
num  target     prot opt source               destination

Chain RH-Firewall-1-INPUT (2 references)
num  target     prot opt source               destination
1    ACCEPT     icmp --  0.0.0.0/0            0.0.0.0/0           icmp type 255
2    ACCEPT     all  --  0.0.0.0/0            0.0.0.0/0           state RELATED,ESTABLISHED
3    ACCEPT     tcp  --  0.0.0.0/0            0.0.0.0/0           state NEW tcp dpt:22
4    ACCEPT     tcp  --  0.0.0.0/0            0.0.0.0/0           state NEW tcp dpt:2000
5    ACCEPT     tcp  --  0.0.0.0/0            0.0.0.0/0           tcp dpts:5100:6000 state NEW
6    ACCEPT     tcp  --  0.0.0.0/0            0.0.0.0/0           tcp dpts:6000:6063 state NEW
7    REJECT     all  --  0.0.0.0/0            0.0.0.0/0           reject-with icmp-host-prohibited
