AD Attribute IPv4Address

Question

Hi all,
I have a question about how / when the IPv4Address attribute gets updated in AD. I'm lead to believe from this Blog (https://www.myotherpcisacloud.com/post/2013/12/02/IPv4Address-Attribute-In-Get-ADComputer.aspx)
that the attribute is not stored in AD but is generated from DNS. The blog indicates this happens every time the command is run however my own testing shows this not to be true.
I have one Domain Controller. It has two NICs. One for backup and one connected to the production network. Only the production network NIC is set to be registered in DNS. If I do an nslookup or a search of DNS only the production IP address is found.
However in AD when doing either a Get-ADComputer or Get-ADDomainController the IPV4address that is shown is the address of the backup NIC.
This is not causing any issues I'm just curious to know more and could find very limited information via Bing(or that other one...). So wondering if anyone has any idea or more information about this attribute or the command lets that are generating it?
Ideally I'd like to get the commands to show the correct IPv4 address.

Answer 1

Hi all,
I have a question about how / when the IPv4Address attribute gets updated in AD. I'm lead to believe from this Blog (https://www.myotherpcisacloud.com/post/2013/12/02/IPv4Address-Attribute-In-Get-ADComputer.aspx)
that the attribute is not stored in AD but is generated from DNS. The blog indicates this happens every time the command is run however my own testing shows this not to be true.
I have one Domain Controller. It has two NICs. One for backup and one connected to the production network. Only the production network NIC is set to be registered in DNS. If I do an nslookup or a search of DNS only the production IP address is found.
However in AD when doing either a Get-ADComputer or Get-ADDomainController the IPV4address that is shown is the address of the backup NIC.
This is not causing any issues I'm just curious to know more and could find very limited information via Bing(or that other one...). So wondering if anyone has any idea or more information about this attribute or the command lets that are generating it?
Ideally I'd like to get the commands to show the correct IPv4 address.
When I read the article you linked, the author states that by disassembling the code, he discovered that this cmdlet doesn't actually retrieve that value/data from AD at all, but instead, the cmdlet performs a DNS lookup on the fly, and, the author goes
on to say that "it won't work very well for computers with multiple IP addresses" (which exactly describes your multihomed dual-NIC DC).
The "correct" IPv4 address, depends on your perspective - are you asking from a machine on the "production" network, or from the "backup" network - the "correct" answer would vary, since production would probably not
route via the backup interface, and, backup would not route via the production interface ?
Also notice that the method returns on the first valid IP address that it finds, so we know that this cmdlet isn't going to work very well for computers with multiple IP addresses.  It would have been trivial to make the cmdlet return an array of
all valid IP addresses instead, but alas, the Powershell developers did not think that was necessary.  And of course if the DNS query fails for any reason, you simply end up with a null for the
IPv4Address field.
Don
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