when are gateways necessary?

[Anonymous]

I have been reading and hearing conflicting information about when gateways are necessary.  Is there an official knowledge article that discusses when they are necessary?

My immediate need is to refresh the data in a Power BI report (i.e., refresh its dataset) that sources from an Excel file that lives in an on-prem file share.  If it matters, ideally, I'd like it to be a scheduled refresh, but I'm okay with it being a manual refresh.  Do I need a gateway for this?

Further, I have 2 more Power BI reports in dev.  Both use an ODBC connection to ServiceNow (cloud, not on-prem).  The first one's connection is to be in import mode (i.e., dataset gets created).  The second one's connection is to be in DirectQuery mode (i.e., no dataset gets created).  Is a gateway needed for either mode?

[galshaked]

The gateway allows access to data that in on-premise, and which Power BI Service cannot access from outside your network. The gateway will connect internallly to the data sources, update the data and send it to Power BI Service. 

https://docs.microsoft.com/en-us/power-bi/service-gateway-onprem

[Anonymous]

Is it safe to say that a gateway is only required for on-prem sources (i.e., not cloud)?  That is, it has nothing to do with the connection mode being import or DirectQuery?

[galshaked]

The way I understand it, yes. 

[Anonymous]

That implies that putting Power BI on top of ServiceNow (i.e., a cloud source) via ODBC in import mode (by default, as ODBC doesn't support DirectQuery) would not require a gateway for refreshes.  However, I am being told by my peers that a gateway is required for refreshes in this scenario.  (Unfortunately, currently, I don't have access to this ODBC driver.  So, I can't test this.)  Are they wrong?

[Anonymous]

@Anonymous we have ServiceNow in the cloud and cannot connect to Power BI because our ServiceNow is allowing only certain IP Ranges. Could your colleagues be mentioning this because you have a similar setup?

Would you have time to talk about the ServiceNow and PowerBI Integration in your environment?

[Anonymous]

@Anonymous 

I think the issue you raised is separate from my issue.  My issue is that I don't know if gateways are needed for cloud sources (e.g., ServiceNow).  And does it depend on the connection method to the cloud source?  That is, if I connect to a cloud source via something like ODBC, does the fact that I'm going through ODBC require a gateway?  Further, does it depend on if the ODBC driver is on-prem vs hosted (e.g., on an Azure VM)?  Independent of the gateway issue, I think whitelisting in ServiceNow the Azure (Power BI) IPs is another issue.  I'm not sure if whitelisting IPs in ServiceNow is even possible.

My company has decided that we don't need real-time / DirectQuery reporting on ServiceNow.  (In fact, our ServiceNow admins won't allow analytical queries ran against it.  So, real-time reporting isn't even permitted in my environment.)  So, we are now going to follow a different integration strategy.  That is, we're going to replicate ServiceNow into an on-prem mirror DB, and put Power BI on top of the mirror DB (instead of on ServiceNow directly).  Obviously, that strategy definitely requires a gateway.