Comparing MSCS/VMware/DFS File & Print

The following table shows information I was using to compare various Windows HA file and print solutions, including MSCS, VMware, VMware+MSCS, DFS, VMware+DFS and stand-alone servers. There are no recommendations, and most need to be adjusted or at least considered for your environment, but it might help crystalise your thoughts as it did mine.

Comparison	Microsoft server Clustering	VMware HA	Microsoft Clustering on VMware HA	DFS	Stand-alone server(s)	VMware HA with DFS for file shares
Highly Available	Y	Y	Y	N	N	Y
Satisfies SLAs	?	?	?	?	?	?
Maximum nodes	8	Limited by host hardware	2	N/A	N/A	Limited by host
Failover time	<2 minutes	VMotion or server startup time	<2 minutes	SPF	SPF	VMotion or server startup time
Single server Disaster Recovery – Software Failure	<2 minutes	Snapshot, server rebuild or manual recovery procedure	<2 minutes	SPF	SPF	pshot, server rebuild or manual recovery procedure
Single server Disaster Recovery – Hardware Failure	<2 minutes	< 30 seconds	< 30 seconds	SPF	SPF	< 30 seconds
Licensing	2003 Enterprise per node	DataCentre + CALs (depending on VM design)	DataCentre + CALs (depending on VM design)	2003 Standard	2003 Standard	2003 Standard
Hardware Failure – Data Communications	Single/teamed NIC for prod interface	NIC redundancy depending on virtual solution	NIC redundancy depending on virtual solution + cluster-specific requirements	Teamed NIC	Teamed NIC	NIC redundancy depending on virtual solution
Hardware Failure – HBA	Single HBA per node	HBA redundancy depending on virtual solution	HBA redundancy depending on virtual solution	Single HBA	Single HBA	HBA redundancy depending on virtual solution
OS Disk Configuration	Basic	Dynamic	Basic	Dynamic	Dynamic	Dynamic
Hardware utilisation	Physical servers	Virtual servers	Virtual servers	Physical servers	Physical servers	Virtual servers
Cost allocation	Cost model required	Cost model required	Cost model required	Per server/LUN	Per server/LUN	Cost model required
Scalability/Flexibility – adding new nodes/LUNs	Y	Y	Y	N	N	Y, DFS for file
Manageability	MSCS skills required	VMware skills required	Complex combination of both technologies	DFS skills required	Existing skills, but increased per server	DFS and VMware skills required
User access to shares via UNC	Single name	Multiple names	Single name	Single name	Multiple names	DFS namespace
Future proofing – migration to new hardware/OS	Moderately complicated migration	Relatively simple upgrade path, reattaching LUNs or adding another VM	Moderately complicated migration	Relatively simple	Relatively simple	Relatively simple
Hardware on Vendor HCL	?	?	?	?	?	?
Backup/restore	?	Standard file backup	VCB or ?	Standard file backup	Standard file backup	VCB or ?
Printer administration	Simplified with Cluster 2003	Duplicated effort on each print server	Simplified with Cluster 2003	N/A	Duplicated effort on each print server	Duplicated effort on each print server
Service and Event Monitoring	Cluster monitoring required	Standard monitoring for virtual servers, host monitoring required	Cluster monitoring for virtual servers, VMware host monitoring required	Standard monitoring	Standard monitoring	Standard monitoring for virtual servers, host monitoring required

1. Basic disks on a Microsoft server cluster can be extended if new space is visible on the LUN. The disks cannot be dynamic in MSCS.
See http://technet2.microsoft.com/windowsserver/en/library/cd4d0a84-6712-4fbc-b099-2e8fefeb694c1033.mspx?mfr=true


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