Quoting from the Hyperic official announcement:
Hyperic Inc., the leader in multi-platform, open source systems management, announced today the availability of the industry’s first virtualization management solution Hyperic HQ for VMware. This pioneering solution enables data centers to consolidate complete discovery, monitoring, analysis and control of all application, system and network assets, both inside and outside of the virtual machines powered by VMware.
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The complete Hyperic HQ for VMware product is now available to all data centers via open source licensing at www.hyperic.com. Hyperic HQ for VMware supports VMware GSX Server and VMware ESX Server 2 and 3…