Crawl component and Query Component are disabled on SharePoint server.

Issue:
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Central admin and Search Application, and found out that one of crawl component on one server status is disabled, and also query component on the same server is disabled.

Root Cause:
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There are various reason like corrupt index, space issue on SharePoint server.

Solution:
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Run the following PowerShell to reset the Query server:

$ssa =  Get-SPEnterpriseSearchServiceApplication -Identity "SSAName"
$queryComponents = $ssa | Get-SPEnterpriseSearchQueryTopology -Active | Get-SPEnterpriseSearchQueryComponent
$component = $queryComponents | where {$_.ServerName -eq "QueryServerName" }

$component.Recover()

Wait for some and see above steps helps recovering query components.

If no luck, you can disconnect the query server from the search topology, stop the Search service in central admin, clear the index files in the query server. After that, starts the search service instance using stsadm -o provisionservice –action command or Start-SPServiceInstance PowerShell.