VI SDK – Beware cached data and assumptions

Applications often cache data and that is good because that generally makes them perform better for users. However, if you make assumptions that what you see is the absolute truth you can run into trouble.

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Connect-ViServer myVirtualCenter001

# Let's check the status of the server to make sure I can go home.
(Get-vmhost myVmHost001.local | Get-View).OverallStatus
green

#Looks good.  Well, maybe not.
(Get-vmhost myVmHost001.local |Get-View).runtime.ConnectionState
disconnected

I know for a fact that this server is not even running VMware at this point so how could I get a green status? Caching. I am not saying that VMware is doing anything wrong in this case, but be aware that your view of the data may not be the most recent.

Always check your assumptions when the data matters.