Polling Daemon

DVG polls the devices either by crontab (exec_rrd.pl) or by an experimental daemon (dvg_snmpd.pl). The problem is - if you use a large installation - the I/O load on the Server. Within a short time all rrd-files are updated and in the same time a lot of updates need to be written to the database.

the new daemon should use multitasking (threads) to distribute the load over the time.

Other things the new daemon should do:

• periodic check the database for new devices (and hosts, locations) (or some notification if someone changes the config, via front- or any back-end-program)
• periodic check for changed parameter. (or some notification if someone changes a parameter, via front- or any back-end-program)
• track the state of a host, at least it should know about following states: up, down, reboot/restart, reachable
• track the state of a device, at least it should know about following states: up, down, shutdown
• notification of the owner
• alarm levels would be nice. if an interface shows some errors, has some unusual drops it would be nice if there are some alarms
• it should be possible to add modules. so the program exec_rrd.pl [exec|modules] is not needed anymore.

are there more needs

Possible Libraries for the implementation: Perl_Object_Environment. Are there other possibilities?

is this a good separation of the different tasks?

• one thread/POE::session to check the database?
• create for each host a thread/POE::session?

open items:

• what if the connection to the database is lost? (snmpd.pl needs to restart)
• communication between the threads specially between the config reader and poller-threads?