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alexchoc's avatar
alexchoc
Regular Visitor
2 years ago

An error occurred while loading the model. Failed to open the MSOLAP connection

Hi, We have an ScaleOUT deployment balanced by Citrix. After start PowerBI windows service works fine for about 2-4 hours. For different reports different users receive error: "An unexpected erro...
@PowerBI Report Server
On Prem
josef78's avatar
josef78
Icon for Memorable Member rankMemorable Member
2 years ago

If I understand, you have scale-out deployment with Citrix NLB?

Not sure, but issue may be in weak NLB persistence (PBI RS (with import mode reports) is not good object for loadbalancing. Check ExecutioLog3 sequence of row for same report request, if actions ASModelStream, ConceptualSchema and QueryData are on same Instance.

Another issue may be in Refresh processing... Are models refreshed during day? Running refresh on dedicated instance of PBIRS? 

Also try turn off NLB, to check if problem is in NLB. For example, in my enviroment, we have also scale-out deployment on three servers, one is dedicated to refresh data, and two as frontend servers, but without loadbalancing, only for failover, or routing based on fixed URL (for specific reports).