Cloud to OnPrem free busy Problem

Aschwanden Roger, ACA-IT-OPE-CIN 1 Reputation point
2021-02-17T13:31:32.293+00:00

Hi
Free/Busy from onPrem to O365 is working but not from O365 to onPrem

I wasn't able to run the HybridConfigurationWizard successfully (did not work with modern or classic). I did some steps manually

Test-OrganizationRelationship is working from O365. All Steps are successfull (also Step4, Retrieved token for target......)

Results www.testconnectivity.microsoft.com
Outlook Connectivity to onPrem Account: successfull exept last check "Attempting to ping RPC proxy ..." (I'm not sure if this must be successfull)
free/busy O365 to OnPrem(Modern Auth): The Autodiscover service was tested successfully
The Autodiscover service couldn't be contacted by any method
free/busy Lookup failed, https status 504 (Gateway Timeout)

I can see autodiscover requests going through our Firwall and F5 LoadBalancer. In the IIS Log can see a lot of entries and I think the one corresponding to this test has a sc-status of 401 (Unauthorized). cs-username is empty.
Probably an missconfiguration of our F5 but I dont think the Problem is there.

It went through a lot of Troubleshooting Guides without success.
Any help is appreciated.

Exchange Server Management
Exchange Server Management
Exchange Server: A family of Microsoft client/server messaging and collaboration software.Management: The act or process of organizing, handling, directing or controlling something.
7,354 questions
Microsoft Exchange Hybrid Management
Microsoft Exchange Hybrid Management
Microsoft Exchange: Microsoft messaging and collaboration software.Hybrid Management: Organizing, handling, directing or controlling hybrid deployments.
1,893 questions
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  1. Lucas Liu-MSFT 6,161 Reputation points
    2021-03-10T09:56:50.357+00:00

    Hi @Aschwanden Roger, ACA-IT-OPE-CIN ,
    1.Since OWA retrieves free/busy information, autodiscover is not needed. Therefore, the configuration of the shared free/busy information itself may cause the issue. Please try to run the following commnd in Windows powershell that is has been connected to Exchange online.

    Get-OrganizationRelationship |Set-OrganizationRelationship -TargetSharingEpr "EWS address of on-premises Exchange server"

    2.If bypassing F5 will not be affected by any rules, then completely exclude the IP address of Exchange online, you need to add all IPs that may be used to the skip list of F5.

    3.Have you considered running HCW again? HCW will once again configure the settings for hybrid deployment.

    In addtion, I noted that there are some email address in the XML file. Not sure if it is your real email address, in order to prevent your personal information, so I removed the XML file first. You could share the results of the test after covering your personal information
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