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I understand from reading http://msdn.microsoft.com/en-us/library/ee790895(v=azure.10).aspx that the more lead hosts you have the better, because if the majority of lead hosts fail, the entire cache cluster shuts down. So is there any reason that we should not just set ALL hosts to be lead hosts, minimising the risk?

I'm using an XML file in a shared folder for the config, no SQL is involved. Sorry if this is a stupid question, I'm brand new to AppFabric and learning from msdn as I go.

Thanks.

Riller '-'
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Best practice is to have at least 3 lead hosts in a small and 5-7 in large cluster. Sync jobs between each lead host will exponentially increase without further improving clusters security. I verified this by asking Microsoft Partner Support.

For small hosting scenarios e.g. with less than 3 cache nodes and where you need an SQL database anywhere it might be an alternative to put Cache Configuration and Cluster Management Role on the SQL Server, using AlwaysOn Availability Groups Feature to ensure High Availability.

Philipp Stauss
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  • Thanks for the reply. So setting all hosts as lead hosts will increase sync time, but the part about it not improving the clusters security gets me. If the majority of lead hosts go down, then the cluster fails, so surely more lead hosts reduces this risk? So for example, if I have 5 hosts, and I set 3 of them as **lead** hosts, then 2 lead hosts go down, the entire cluster of 5 goes down; but if I set all 5 to be lead hosts, then it needs 3 of them do go down before the cluster fails, so is more secure surely? Am I thinking about this wrongly? – Riller '-' May 14 '14 at 13:31
  • Exactly. For your scenario pros and cons must be weighed. You have to find the right balance. – Philipp Stauss May 21 '14 at 09:59
  • If the answer solved your problem please mark it as solved with the green checkmark. – Philipp Stauss May 28 '14 at 12:49