How much space needed for HA Shared storage PRPC7.1.7
If I have a cluster of 5 Server and each server has 100 users and the Clipboard for each user is 30MB. How much Shared Storage do I need for the HA to be able to move these users across the cluster?
Is there a rule of thumb for calculating storage?
Pegasystems Inc.
US
Hi Audlian,
It is tempting to simply do 100x30x5. Well, given the consequences of out of disk (often causing system outage and shared storage has become single point of failure for HA), I would suggest run 'realistic' load tests with your cluster with HA not enabled. Get the maximum disk space used among all nodes, then times that with number of nodes and then time a factor of 2 to 3. Storage these days is fairly inexpensive but a full disk space will cost you more in terms of business loss due to system outage. You should be aware that starting 7.1.9, database will be the default passivation storage if HA is enabled, so you do not have to worry about that anymore.
American Express
US
Thanks for the response Kevin. As of now there is no plans to move to 7.1.9 at this time. So I am going to stick with you suggestion going forward. I am going to use the following formula.
((Number of Users X Size of Clipboard X Number of nodes in the cluster) X 2)
This I will use as starter until we can do a complete stress test of the system. Please advise.
Thanks for the quick response.