SBS 2003 - DNS/DC slow log on issue for one user.

E

Easius

Limp Gawd
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Jan 1, 2009
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Have a small business 2003 server that is the domain controller. Have one user let's call smith. Smith can join the domain when I set auto obtain for the DNS server, however it takes a very long time to log in, and he has had minor issues when logged in as well. When it auto obtains it doesn't get the DC as the DNS server. However all the other 30 users connect instantly when I manually set the DNS to the DC's IP. When I set his DNS manually to the DC's ip (Let's say 192.168.0.1) and then ipconfig /flushdns he gets the corrent dns of 192.168.0.1 but then when I try to log on to the domain it says 'Cannot find the domain controller' yet auto obtain lets it work?

Any idea why smith can not connect to the domain with DNS set manually, yet it works on automatic obtain, but takes a very long time to log in.

Thanks.
 
what IP is being received when it receives DNS via DHCP? Is it not the same as the DC?
what's the TCP/IP settings on the DC? Does it have the primary DNS set to it's own IP?
 
Easius said:
Have a small business 2003 server that is the domain controller. Have one user let's call smith. Smith can join the domain when I set auto obtain for the DNS server, however it takes a very long time to log in, and he has had minor issues when logged in as well. When it auto obtains it doesn't get the DC as the DNS server. However all the other 30 users connect instantly when I manually set the DNS to the DC's IP. When I set his DNS manually to the DC's ip (Let's say 192.168.0.1) and then ipconfig /flushdns he gets the corrent dns of 192.168.0.1 but then when I try to log on to the domain it says 'Cannot find the domain controller' yet auto obtain lets it work?

Any idea why smith can not connect to the domain with DNS set manually, yet it works on automatic obtain, but takes a very long time to log in.

Thanks.
Click to expand...

Sounds like his source of DHCP is something other than your SBS box. Is his wireless latching on to a nearby wireless network by accident? Or can you ensure that his ethernet cable is plugged into the correct LAN switch (in case your office shares a building with other offices in a professional center and you all share a wiring closet).

You've already discovered that he is not getting the proper DNS..now you have to find out why. My first hunch is "what is he connecting to".
 
what IP is being received when it receives DNS via DHCP? Is it not the same as the DC?
what's the TCP/IP settings on the DC? Does it have the primary DNS set to it's own IP?
Click to expand...

It's getting my DNS from my ISP when it is set to auto-obtain. The DC does have it's primary DNS set to localhost.



YeOldeStonecat said:
Sounds like his source of DHCP is something other than your SBS box. Is his wireless latching on to a nearby wireless network by accident? Or can you ensure that his ethernet cable is plugged into the correct LAN switch (in case your office shares a building with other offices in a professional center and you all share a wiring closet).

You've already discovered that he is not getting the proper DNS..now you have to find out why. My first hunch is "what is he connecting to".
Click to expand...

No wireless.
Have tried another cable run already that works fine.
 
ok... so what's the DHCP server?
is it atleast receiving an internal IP?

your DHCP server should be handing out the DC's IP address as the primary DNS server.
but it doesn't sound like this is what's happening, if DHCP-received DNS is pointing to your ISP's DNS.
 
DHCP server is a sonicwall tz-210. It's assigning the same DNS it's using, granted I could set it to the DC's IP, but even so, when I manually set the ip and flush the DNS cache on the local pc, it still should be working. It shouldn't matter what the DHCP router is assigning when it's set to manual and still not working.
 
Shouldnt the TZ-210 not be assigning IP's?
Im guessing your setup is as follow:>
TZ210-------|(switch)
SBS---------|(switch)
PCS---------|(switch)
The TZ210 should have a manual IP on the inside/LAN port, an IP that matches your SBS machine network, NO DHCP on the TZ210.
Then your SBS should have a manual IP, with itself as primary DNS, DHCP on the SBS.
On the DNS server, you should have OpenDNS or your ISP DNS servers, or maybe the TZ210 (pref ISP or OpenDNS though)
All clients would be auto obtain and they should get an IP from your server, with your server giving out the DNS server (your SBS IP), gateway (the internal IP of the TZ210) and subnet.
 
Easius said:
DHCP server is a sonicwall tz-210.
Click to expand...

Why is a router doing DHCP when you have a DC on your network..have the DC do it, let your server do its job. Workstations register better with active directory when a DC is a DHCP server.

Your workstations at the office should be getting the IP of your SBS box as their DNS server...not the router, not the ISPs DNS server...but only only only your DC(s).
 
YeOldeStonecat said:
Why is a router doing DHCP when you have a DC on your network..have the DC do it, let your server do its job. Workstations register better with active directory when a DC is a DHCP server.

Your workstations at the office should be getting the IP of your SBS box as their DNS server...not the router, not the ISPs DNS server...but only only only your DC(s).
Click to expand...

Yea it sounds like he has the public dns showing up. While the sonicwall is fine at running the dhcp you need to manually tell it to point the dns to the server for the dhcp service. Personally I'd let the SBS box run dhcp.

In the DNS manager on the sbs machine you can click on the server and go to properties and go under forwarders. You can put the isps dns in there.
 
swatbat said:
In the DNS manager on the sbs machine you can click on the server and go to properties and go under forwarders. You can put the isps dns in there.
Click to expand...

Or better yet....OpenDNS servers....give an added layer of protection from malware to your network.;)

I always like the DC to run DHCP rather than having a router do it.
A servers DHCP service is more configurable..more options, proper DNS names, WINS types (SBS runs WINS by default..helpful with WANs) and many routers don't have options to configure these.
Also running DHCP from the server allows DNS and active directory to run better, dynamic DNS updates instead of ARP queries to keep track of nodes.
 
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