What is the full form of ISTG

ISTG: Inter Site Topology Generator

ISTG stands for Inter Site Topology Generator. It is defined as replication among sites on a said network. ISTG is also known as the Active directory process. Each site's only domain controller is autonomously chosen to serve as the inter site topology generator, and these sites are responsible for creating their intrasite connection object.

Functions Of Inter Site Topology Generator

In the Inter Site Topology Generator, there is no extreme necessity to recognize the replication topology and bridgehead server roles by human beings, as the inter site topology generator performs all these tasks automatically. The inter site topology generator role, which the domain controller holds, performs two functions which are as follows:-

1. To form bridgehead servers, one or more domain controllers are chosen automatically. Hence, whenever possible, another bridgehead server gets automatically selected when one of the servers becomes unavailable for some reason.
2. KCC is used to recognize the duplication of topology and resultant connection objects. This, in turn, assists the bridgehead servers by communicating with bridgehead servers of other sites.

What Is Bridgehead Server?

A domain controller that works as the primary route of Active Directory replication data moving in and out of the sites is known as a bridgehead server. It can be understood that if there is more than one bridgehead server, you will indeed have more than one domain. Bridge uses connectivity physically by using the interim site for the Inter Site Topology Generator. This did not imply that it would be the domain controller to provide a replication path in the interim site.

Way To Move ISTG Manually To Any Other Given Server?

One active directory component, called the Knowledge Consistency Checker (KCC), is responsible for generating replication topology amongst the various domain controllers. For each site, one domain controller is held accountable for the role of the Intersite topology generator. This is then held responsible for managing all the inbound replicating connection objects for all bridgehead servers located on the site. The responsibility to create automatically generated connecting objects is given to inter state topology generator whenever more than one domain controller is present in your unit, as seen in the Sites and Services of the Active Directory. Inter Site Topology Generator is manually moved to another server. In the following ways:-

1. Open ADSIEDIT.msc
2. Expand Configuration [Domain Controller].
3. Expand CN=Configuration, DC=<domain>,DC=<com>.
4. Expand CN=Sites.
5. Highlight CN=<site name> for the site where the ISTG server is to be changed.
6. Right-click on CN=NTDS Site Settings, and in the details panel, select Properties.
7. It will be visible which Domain Controller is designated as the ISTG server as soon as you locate the Inter Site Topology Generator attribute.
8. Select the Edit option and then change the name of the server.

How To Find The Inter Site Topology Generator For Any Given Site?

There are two methods to search the Inter Site Topology Generator (ISTG) for a site.

A. Using A Graphical User Interface

1. First, open the Services snap-in and Active directory sites.
2. Select and open the site you are interested in.
3. Double-click on the NTDS Site Settings objects in the right pane.
4. ISTG will be displayed under the Inter Site Topology Generator.

B. Using A Command Line Interface

This command is available only with the Windows Server 2003 version of repadmin, > repadmin /istg <Domain Controller Name> USING VBSCRIPT -

' This code finds the ISTG for the specified site.