Help Setup KMS on single domain and active for multiple domain another

Question

Hi all,
I have a problem about configure DNS for KMS host. My company use a single domain "abc.com". But I must mange more than 10 company different and they use another domain and dns running independently, they have a one lease line connect them together.
My challenge is how to active all client on more than 10 company. Any ideas is very appreciate.
Please help.
Thanks,

Answer 1

That's a good article suggested by Meinolf, but it's a little outdated.
For an updated guide for this:
https://technet.microsoft.com/en-us/library/ff793409.aspx
Publishing to Multiple DNS Domains
By default, the KMS host is registered only in the DNS domain to which the host belongs. If the network environment has only one DNS domain, no further action is required.
If there is more than one DNS domain name, you can create a list of DNS domains for a KMS host to use when publishing its SRV RR. Setting this registry value suspends the KMS host’s default behavior of publishing only in the domain specified as the Primary
DNS Suffix.
Optionally, add priority and weight parameters to the
DnsDomainPublishList registry value for KMS. This feature enables you to establish KMS host priority groupings and weighting within each group to define which KMS host to try first and balance traffic among multiple KMS hosts.
Note   DNS changes might not be reflected until all DNS servers have been replicated. Changes made too frequently (time < replication time) can leave older records if the change is performed on a server that has not been
replicated.
To automatically publish KMS in multiple DNS domains, add each DNS domain suffix to whichever KMS should publish to the multi-string registry value
DnsDomainPublishList in registry subkey HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\SoftwareProtectionPlatform. After changing the value , restart the Software Licensing Service to create the SRV RRs.
Note   This key has changed from the Windows Vista location of
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\SL.
After configuring a KMS host to publish to multiple domains, export the registry subkey, and then import it in to the registry on additional KMS hosts. To verify that this procedure was successful, check the Application event log on each KMS host. Event
ID 12294 indicates that the KMS host successfully created the SRV RRs. Event ID 12293 indicates that the attempt to create the SRV RRs was unsuccessful. For a complete list of error codes, see the
Volume Activation 2.0 Operations Guide at
http://technet.microsoft.com/en-us/library/cc303695.aspx.
Don
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