DHCP Server Migration From Windows Server 2012 R2 to Windows Server 2016

With the end of main stream support coming up in a few months, I decided to start upgrading my lab environment to Windows Server 2016. I started with Active Directory and it's related services like DHCP.

In this article we'll migrate the DHCP service from a machine running Windows Server 2012 R2 to one that's running 2016.

The first step of the process would be to install and configure the DHCP server role on the new machine. I'm not going to describe the installation process since it's fairly simple, I will however show you the post installation configuration.

The first screen is the description of the operation, followed by the authorization step:


Here, we have to select the account that is going to be used in order to authorize the server:


On the last step, the server is authorized and the groups used for delegating access are created:


Now that our new DHCP server is ready, we have to migrate the configuration from the old one.

The server dc1 currently has two IPv4 scopes as shown below. The server dc3 is the new DHCP server that does not have any scopes yet.


The "Export-DHCPServer" cmdlet exports the configuration and leases from a server to a file:
Then, we can use the "Import-DHCPServer" to import the configuration from the file:
The options and scopes have been imported on the new server.


The last step is to disable the scopes on the old server:

Now that the scopes are disabled, the clients will not be assigned addresses from the old server.


That's it! Don't forget to remove the file created on the export step!


Popular posts from this blog

Domain Controller Machine Password Reset

Image
On my lab environment, I've configured two Active Directory sites since most enterprises have offices in more that one places. My lab however is not running 24/7 and the domain controllers in the second site are rarely turned on in order to save resources. This leads to issues with the Active Directory replication such as the "The target principal name is incorrect" error when I execute:  repadmin /syncall /AdeP. To remedy the issue, we have to reset the machine password of the domain controller that has been offline. First off, we are going to stop and disable the Kerberos Key Distribution Center (kdc) service on the problematic domain controller, in our case DC4. There may be some tickets in the cache so we should also clear them using klist purge Now it's time to change the machine password of the domain controller using the command netdom resetpwd /s:dc3 /ud:lab\administrator /pd:* Replace the "lab\administrator" with an account on your...
Keep reading

Managing Active Directory User Certificates using PowerShell

I first came across user certificates when I was working with email certificates a few years ago and I have to admit that I had trouble updating the certificates on the objects! Most organizations have a Microsoft Active Directory Certification Authority that issues the certificates used internally. When a certificate is issued to a user, the Microsoft Certificate Service saves the public key in Active Directory. The userCertificate attribute is a multi-valued attribute that contains the DER-encoded X509v3 certificates issued to the user. Although we rarely need to pay attention to this attribute, there are cases where we have to update it. To make things easier, I've written PowerShell functions to Get, Remove, Import and Export the certificates on that field. To get the list of certificates for an object, use the Get-ActiveDirectoryObjectCertificate function: PS C:\> Get-ActiveDirectoryObjectCertificate -UserPrincipalName cpolydorou@lab.local DistinguishedName  ...
Keep reading

Configuring a Certificate on Exchange Receive Connector

Today's article is about configuring Exchange receive connectors with specific certificates. Out of the box, Exchange uses self signed certificates to provide TLS secured mail flow. This will definitely be an issue if you expose the SMTP protocol to client computers since they won't trust the certificate. In this article we are going to configure a certificate that was issued by a third part authority to the Client Frontend receive connector. We'll start with getting the thumbprint of the certificate using the Get-ExchangeCertificate cmdlet: [PS] C:\> Get-ExchangeCertificate Thumbprint                               Subject ----------                               ------- 241B864DC82C664FECBA18B8D54987AAFB65B4C2 CN=*.lab.com, ... D4D210886B34E690191A1F008C78FDD0E7325DD4 CN=Exchange2013A 960171662EB26116...
Keep reading