Recently, We were facing issues with index out of sync errors, We have tried everything possible to get the indexers to sync and at last resort, nuclear option, to reset the Search Index.
In my case the index is out of sync & never catches up, the index components are yellow in topology view.
In the SP management console run:
$ssa = Get-SPEnterpriseSearchServiceApplication
get-spenterprisesearchstatus -SearchApplication $ssa -Detailed -Text
What I have found is that sometimes the reset index process hangs and there is no documentation as to what to do about it.
On the SSA you will see something like this:
Administrative status Paused for:Index reset
Administrative status Paused for:External request, Index reset
Administrative status Paused for:External request
You can run this command in the SSA management console to verify if the SSA is paused. If this command returns False, the SSA is running. If this command returns True, the SSA is paused.
$ssa.IsPaused() -ne 0
This is the most common I have been seeing with indexers out of sync and reset index stuck:
($ssa.IsPaused() -band 0x100) -ne 0
If True returns the search index is being deleted and you must “Wait until the search index is deleted.”
Well if your indexers are out of sync this can take many many hours or never return!
(If False you may want to look at the link at the bottom for more commands on this to see why the SSA is still paused, could be a backup or topology change, etc)
Here is the process I have been able to use to fix this issue:
#1 First try to force a resume, if this doesn’t work that’s fine and go to #2 anyways, just more of a try a last ditch force.
#2 On all of the nodes that contain an indexer component, stop the timer services and delete the indexes:
Stop “SharePoint Timer Service”
Stop “SharePoint Search Host Controller”
Delete data directory, by default install it will look like this:
C:\Program Files\Microsoft Office Servers\15.0\Data\Office Server\Applications\Search\Nodes\[Hex ID\IndexComponentN\storage\data\*
Start “SharePoint Timer Service”
Start “SharePoint Search Host Controller”
#3 Once they directories are deleted, run reset index again (which should complete very quickly)