Clients get wrong DNS

[Tom Elliott]

To me this sounds like you have multiple DHCP? I don’t know.

Can you show us a copy of your /etc/dhcp/dhcpd.conf file?

[Quazz]

Afaik, clients will retain old information on Windows until they checkin for a new lease.

[Wayne Workman]

Go over to a computer on that subnet and (assuming windows) run this command: ipconfig /release && ipconfig /renew and then see what DNS address it’s using.

[Tom Elliott]

@Wayne-Workman I think another form to ensure all is routing properly would also work:

ipconfig /flushdns

[Quazz]

@Tom-Elliott This would work only if the DHCP information is correct, I believe.

[Tom Elliott]

@Quazz That’s why it’s suggested as an “additional” step.

[Warrender6]

Thanks for your help!
Here is the config.

The clients are not the problem. I run these commands before I started this thread.

[Quazz]

@Warrender6 This looks like a very old generated file.

At any rate, try adding authoritative; before the subnet declaration.

[Warrender6]

@Quazz
Thanks!
I´m not completely sure what you mean.
Should i edit the file like this?

…
next-server 172.28.0.230;
option domain-name-server 10.66.109.10;

subnet…

[Quazz]

@Warrender6

No, simply add authoritative; there.

[Warrender6]

@Quazz
Should there be a link?

[Quazz]

@Warrender6 …a link? No, it’s a DHCP option…

[Wayne Workman]

@Warrender6 Here’s an example. You should just re-write this whole configuration. ISC-DHCP can support both BIOS and UEFI at the same time, you don’t need to go in there commenting and uncommenting filename lines.
https://wiki.fogproject.org/wiki/index.php?title=BIOS_and_UEFI_Co-Existence#Example_2