Vmware

In order to replicate data from the MD3000i, some type of host based software will be needed. There are two basic options here - Run a replication agent inside the VMs or run an agent on ESX. When running an agent inside the VM you can replicate just the data. When running an agent from ESX you will be able to replicate the entire VM.

Doubletake sofware (www.doubletake.com) has products that will do both with DoubleTake for Windows and DoubleTake for VMware Infrastrucure. VizionCore (www.vizioncore.com) has vReplicator that will replicate VMs from the ESX level. Additionally, VMware is working on VMSite Recovery Manager that will provide replication and recovery tools. It has been announced, but is not available yet.

Todd

Let me add some additional information. Double-Take does in-fact allow total system replication with several of our products. That includes the OS, Applications and Data. The two biggest differentiators between Guest-based replication and Host-based (i.e. ESX) replication are as follows:

1. Data selectability: Host-based replication tools (yes, we have one too) forces you to protect the entire machine without any granularity. How is that bad, you say? Well, Host-based replication can't tell the difference between a database write and a pagefile write or a file system defrag for that matter. Pagefile is completely non-recoverable, so there's no point in protecting it. Thus Host-based ESX replication forces you to use dramatically more bandwidth with this type of replication technology.

2. Transactional Integrity cannot be guaranteed with Host-based ESX-style replication without forcing a quiesce to guarantee that the entire database is persisted to a good consistent state. Whereas Double-Take running within the Guest CAN provide that guaranteed data integrity. It's all about the integration point. Here's a doc that explains further (http://www.doubletake.com/_docs/pdf/HowDoesDTEnsureDataIntegry2006.pdf).

Double-Take has understood for a very long time that certain types of servers genuinely need full server protection; thus we created our unique system state protection technology 2 years ago. It allows you to protect the entire machine, without sacrificing data integrity or replicating so many unnecessary gigabytes.

Try it out for yourself, an idle Guest with no users generates around 25 Megabytes an hour while doing nothing. Double-Take running inside the Guest ignores the vast majority of that change because it's mostly pagefile.sys writes.

Regardless, don't go it alone. Contact us and one of our Solution Architects can walk you through all your options.

Best regards,

Nicholas Schoonover