That’s pretty much what we have here as well. We added a static route to each
of the domain controllers via DHCP option 33 and it resolved the problem.
--
There are 10 kinds of people in the world...
those who understand binary and those who don't.
From: [email protected] [mailto:[email protected]] On
Behalf Of Chad Leeper
Sent: Thursday, November 17, 2016 2:56 PM
To: [email protected]
Subject: RE: [NTSysADM] Windows 7 asking for network after expanding dhcp range
form /24 to /22
No there is not a DC on /22. Interesting idea though and it makes sense. Both
of my DCs do triple duty as DHCP and DNS. (only 117 nodes.)
From: [email protected]<mailto:[email protected]>
[mailto:[email protected]] On Behalf Of Melvin Backus
Sent: Thursday, November 17, 2016 1:15 PM
To: [email protected]<mailto:[email protected]>
Subject: RE: [NTSysADM] Windows 7 asking for network after expanding dhcp range
form /24 to /22
Is there a DC on the /22? You may need to include a route in the DHCP spec to
tell machines how to find the/a DC if they live on the /24 which is sounds like
they might. This sounds similar to a problem we had when we went from a flat
/24 network to multiple /24 vlan subnets.
--
There are 10 kinds of people in the world...
those who understand binary and those who don't.
From: [email protected]<mailto:[email protected]>
[mailto:[email protected]] On Behalf Of Chad Leeper
Sent: Thursday, November 17, 2016 1:51 PM
To: [email protected]<mailto:[email protected]>
Subject: RE: [NTSysADM] Windows 7 asking for network after expanding dhcp range
form /24 to /22
My DHCP servers live on the /24 network. Yes, I do have Helper IPs configured.
From: [email protected]<mailto:[email protected]>
[mailto:[email protected]] On Behalf Of Don Ely
Sent: Thursday, November 17, 2016 10:27 AM
To: [email protected]<mailto:[email protected]>
Subject: Re: [NTSysADM] Windows 7 asking for network after expanding dhcp range
form /24 to /22
Where does the DHCP server live? Do you have IP helper/DHCP relay configured
on the L3 interface for your new /22 VLAN?
On Thu, Nov 17, 2016 at 8:01 AM Chad Leeper
<[email protected]<mailto:[email protected]>> wrote:
All,
So when my network was originally created (Novell 3.x) the admin at the time
used a /24 address for static AND dhcp range.
Fast forward 20 years and we are running out of addresses. I have kept all
static devices on /24 but, have setup a new dhcp scope on /22.
We have Hp switches connecting everything and Ubiquity edge routers are doing
the heavy lifting. i.e. routing between vlans
I am testing a few pcs now just to make sure everything is happy. (untagging
the new vlan on a few specific ports)
Everything works as it should. BUT here is the rub….
When a test machine boots up the user cannot initially log in. (No logon
servers available)
Logging in as local admin, selecting work network when prompted, then disabling
and reenabling the NIC gets the machine back on the domain network with
the correct IP from the new scope. Which is horrible to have to do for each pc.
I think I can get around it with some router trickery so that everything comes
in and goes out on the same interface but, that does not seem like the most
efficient.
(The MAC address would remain in the same “bucket” for lack of a better word.)
Anyone been down this road before and have some words of wisdom? Windows 2008
r2 domain, Win 7 pcs.
Thanks,
/Chad
