Good Day,We have two Microsoft Office 365 Index Servers configured in a load-balanced setup.The index disk on Index Server A became full, so I ran the Load Balance Index Server workflow. After the workflow completed, the index data was moved/copied from Index Server A to Index Server B.Since then, we have been experiencing issues accessing the Index Server and index-related operations are no longer functioning correctly.Could you please clarify:Why are the Microsoft Office 365 backup indexes not automatically distributed across both Index Servers when load balancing is configured? What is the recommended method to rebuild or recover the indexes after running the Load Balance Index Server workflow? How can we restore normal Index Server operation in this scenario?We are running on SP 11.40.67 Error: Exchange index stats failed for subclient [4107] with message [Exception of type 'Commvault.InfoRetrieval.SearchServerException' was thrown.] Unknown error, Webserver failed to process Idx retention rules. Error msg:[E] (ErrNo.1001)

Question

Rebuild Indexing for MS Ofdfice 365

Forum|Forum|2 days ago
September 21, 2026
3 replies
31 views

E

+17

Egor Skepko
Explorer

Good Day,

We have two Microsoft Office 365 Index Servers configured in a load-balanced setup.

The index disk on Index Server A became full, so I ran the Load Balance Index Server workflow. After the workflow completed, the index data was moved/copied from Index Server A to Index Server B.

Since then, we have been experiencing issues accessing the Index Server and index-related operations are no longer functioning correctly.

Could you please clarify:

Why are the Microsoft Office 365 backup indexes not automatically distributed across both Index Servers when load balancing is configured?
What is the recommended method to rebuild or recover the indexes after running the Load Balance Index Server workflow?
How can we restore normal Index Server operation in this scenario?

We are running on SP 11.40.67

Error:

Exchange index stats failed for subclient [4107] with message [Exception of type 'Commvault.InfoRetrieval.SearchServerException' was thrown.]

Unknown error, Webserver failed to process Idx retention rules. Error msg:[E] (ErrNo.1001)

E

+1

edso
Apprentice
Forum|Forum|1 day ago
September 22, 2026

Hello Egor,

if I remember correctly, there should be a workflow called “Office 365 Index Server DR Status” in the command center. In this workflow you can create a new request and choose an operation and application for which you want to move the index. You can then pick the target Index (the new index server which has to have the index packages installed) and move it there.

Thats what I have done when I had to move our O365 index and it worked fine. Not sure if the “Load Balancing Index Server Nodes” is the correct workflow.

Like

E

+17

Egor Skepko
Author
Explorer
Forum|Forum|1 day ago
September 22, 2026

@edso

Wel i am trying to do reconstruction but its failed on Office365IndexserverDRWorker phase.

I also tried reinstalling the software and adding the node back to the index, but I then see the following message in the IndexServer log:

D:\hdsdata\IndexCache\CvIdxLogs\2\D20E1599-0D73-46BA-A363-32A4D15F23FC\J8658068\D20E1599-0D73-46BA-A363-32A4D15F23FC\796ddd96f71325a2926a052ec0c0009c\default\default\00000001.al] with error [0xECCC03E9:{I2::SolrEngineInfo::setUpdateHandler(146)} + {I2::SolrEngineInfo::flushDocuments(208)/ErrNo.1001.(Unknown error)-failed to flushdocuments. url[/solr/UM_D20E1599-0D73-46BA-A363-32A4D15F23FC_multinode/update]}]