Using Powershell to change registry keys for search crawler

In one of my earlier posts, I described a way to use PowerShell to change settings in a SharePoint 2007 farm.  That started out as my first PowerShell script and I have witnessed the power behind it all.

In our project, we needed a server wide adjustment of the registry for the SharePoint index servers across all farms. Of course, multiple ways to do this, but here is where PowerShell shows its power. I needed to change two registry settings, both covering the maximum file size that is crawled by the indexer. By default, this is 16 MB (mutiplied by 4), leaving a total of 64 MB indexed in each file. As we now enlarged trhe maximum upload size to 100 MB, we needed the crawl settings to be adjusted. To be honest, I was quite surprised it would only take me two lines of script to make this work. The registry keys in question were those below:

HKLM\SYSTEM\CURRENTCONTROLSET\
HKLM\SOFTWARE\MICROSOFT\OFFICE SERVER\12.0\SEARCH\GLOBAL\GATHERING MANAGER

And to change these, the following lines of script would suffice. I have also added some additional lines to check whether we actually are at the index server, otherwise, these changes would have no effect. Pay special attention to the way the registry is accessed. In principle, it is accessed as a file path.

Set Search Crawler Settings

Write-Host “Set registry values for search”
Write-Host “=======================================================================”
Write-Host “”

if ( (Get-Itemproperty  -Path “hklm:\SOFTWARE\Microsoft\Office Server\12.0\Search\Global”).Index -eq 1 ) {
    Write-Host -f green “Validated that this server is the index Server ” 
} else  {
    throw “This server is the not the SharePoint index Server ” 
}

Write-Host “Processing MaxTextFilterBytes”
set-itemproperty “hklm:\system\currentcontrolset\control\contentindex” MaxTextFilterBytes -type “DWord” -value “104857600” -force

Write-Host -f green “Done…”
Write-Host “Processing MaxDownloadSize”
set-itemproperty “hklm:\software\microsoft\office server\12.0\search\global\gathering manager” MaxDownloadSize -type “DWord” -value “26214400” -force

Write-Host -f green “Done…”
Write-Host -f green “Script completed”
Write-Host “=======================================================================”
Write-Host “”

In addition to these registry changes, a couple of more settings need to be set to get the entire maximum upload size working. Above registry changes instruct the search crawler to enlarge the crawled file size. But this still does not allow SharePoint to upload larger files.  Besides SharePoint changes, OS level changes also need to be make on the client side to allow the WebDAV protocol to upload larger files. These are however out of scope of this blog post. In short, three steps are needed to support larger files on SharePoint:

1. Change the crawler settings to support larger files in the registry.
2. Change the Maximum File Size for the Web Application.
3. Change the connection time out setting on the SharePoint search service. (OSearch)

To change the crawler settings, the PowerShell script is located above. To execute steps 2 and 3 in above list, the following PowerShell scripts do the job:

Set Maximum File Size for Web Application

[Void][System.Reflection.Assembly]::LoadWithPartialName(“Microsoft.SharePoint”)
$farm = [Microsoft.SharePoint.Administration.SPFarm]::Local
if ($farm -eq $null ) {
    throw “Could not connect to the SharePoint farm”
}

Write-Host “”
Write-Host “====================================================================”
Write-Host “”
$websvcs = new-object  Microsoft.SharePoint.Administration.SPWebServiceCollection($farm)
if ($websvcs.Length -eq 0 ) {
    throw “Could not connect to any SharePoint Web Service in the farm”
}
$FileSize = 100
$MaximumFileSize = 0

foreach ($websvc in $websvcs) {
    foreach ($webapp in $websvc.WebApplications) {
 if (($webapp.MaximumFileSize -ne $FileSize) -and ($webapp.MaximumFileSize -lt $FileSize))
     {
  Write-Host “Set file size for web application $webapp.Name”
  $webapp.MaximumFileSize = $FileSize
  $MaximumFileSize = $webapp.MaximumFileSize
  $webapp.Update()
  Write-Host -f green “New file size $MaximumFileSize MB”
 } else {
         Write-Host -f green “Maximum file size for $($webapp.Name) was already set to or larger than $FileSize MB”
 }
    }
}
Write-Host -f green “Script completed”
Write-Host “====================================================================”

Set Connection TimeOut for Search Crawler

[Void][System.Reflection.Assembly]::LoadWithPartialName(“Microsoft.SharePoint”)
$farm = [Microsoft.SharePoint.Administration.SPFarm]::Local
if ($farm -eq $null ) {
    throw “Could not connect to the SharePoint farm”
}

Write-Host “====================================================================”
Write-Host “”

$searchsvcs = @($farm.Services | where -FilterScript {$_.GetType() -eq [Microsoft.Office.Server.Search.Administration.SearchService]})
if ($searchsvcs.Length -eq 0 ) {
    throw “Could not connect to any SharePoint Search Service in the farm”
}

$TimeOut = 90
foreach ($searchsvc in $searchsvcs) {
    if (($searchsvc.ConnectionTimeOut -ne $Timeout) -or ($searchsvc.AcknowledgementTimeout -ne $Timeout))
    {
        Write-Host “Set connection and acknoledgement timeouts for $($searchsvc.Name) to $Timeout”
        $searchsvc.ConnectionTimeOut = $Timeout;
        $searchsvc.AcknowledgementTimeout = $Timeout;
        $searchsvc.Update()
 Write-Host -f green “Done…”

    } else {
        Write-Host -f green “Connection timeout for $($searchsvc.Name) was already set to $Timeout”
    }
}

Write-Host -f green “Script completed”
Write-Host “====================================================================”

Thats it! Using three simple scripts, we can change the settings in our entire farm to use new file upload settings and have it supported by the sarch crawler.

CU!