Add Search component to search topology

SharePoint 2013 change search tapology. You cannot change it directly so the way to do it to clone it, modified it and make clone active

Let say you want to add admin component to server P11

1.      Clone current Search Topology

$ssa = Get-SPEnterpriseSearchServiceApplication
$active = Get-SPEnterpriseSearchTopology -SearchApplication $ssa -Active
$clone = New-SPEnterpriseSearchTopology -SearchApplication $ssa -Clone –SearchTopology $active

2.      Add new Search component to P11 (server name)

$app2 = Get-SPEnterpriseSearchServiceInstance -Identity "P11"

New-SPEnterpriseSearchAdminComponent -SearchTopology $clone -SearchServiceInstance $app2


3.      Start new search component

Start-SPEnterpriseSearchServiceInstance -Identity $app2


4.      Activate Cloned Topology (this will make clone active)

Set-SPEnterpriseSearchTopology -Identity $clone

Ref: http://stevemannspath.blogspot.com/2013/03/sharepoint-2013-search-moving-query.html