Currently viewing the tag: "HA"

n+1 is hogwash!

By On 15 February 2010 · 3 Comments

Too frequently I hear the expression n+1 as a model for ESX clusters to provide High Availability.  If you EVER expect to patch ESX servers without VM downtime then you need at least(†) n+2.  When running your clusters to only n+1, you can never safely put one of your hosts in Maintenance Mode; not if High Availability is important [...]

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VMworld: HA

By On 5 September 2009 · Leave a Comment

While attending the HA: Internals and Best Practices session (BC3197) on Tuesday afternoon, I learned something new about HA’s VM health monitoring.  With a cluster’s HA, you can set it to monitor the health of your VMs and have them automatically restart if it detects an OS hang-up.  To do this it uses a heartbeat [...]

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