Zenoss is an open source agentless monitoring tool. The main advantage of zenoss is that you don’t need to install any software on the client side for monitoring. Zenoss has the following two versions: Zenoss Core (this is free) Zenoss Enterprise. This is also called as Zenoss Resource Manager, which is a paid version.
Enterprise Networking Planet: "Open source network monitoring and management vendor Zenoss is out this week with a new version of its commercial Zenoss Enterprise platform. Zenoss Enterprise 3 is built on an open core model, with the core product based on the Zenoss Core open source project and including some proprietary bits on top."
Zenoss Core has lot of daemons that can be used for various purpose. While you might not use all of the daemons in your Zenoss environment, it is still essential for you to understand all available zenoss daemons, which you can use to solve a specific enterprise monitoring requirement.
Zenoss Inc., corporate sponsor of the award winning open source IT monitoring and management solution Zenoss Core, today announced the general availability of Zenoss Core version 2.5.2 under the GNU General Public License (V2). As part of this release, Zenoss Core now offers new monitoring capabilities for the Xen Hypervisor via the Zenoss Xen monitoring plug-in, or Xen Virtual Hosts ZenPack.
I am using Zenoss for monitoring purpose .And I had been using its mail service for long time .Suddenly my mail service in zenoss stopped and started showing <class 'smtplib.SMTPServerDisconnected'> - Connection unexpectedly closed and no mails are outgoing .When I ran the mail command via CLI , the mail goes to the email address .While executing the zenoss script for mailer wont work and t