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DavidBurchettFlag for New Zealand

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Help with setting up DNS and Connectivity

Hi,

I've recently upgraded our old SBS200 to version 2003 Premium. We upgraded the hardware at the same time and did a new and full installation onto newly formatted hard drives.

The setup is one nic on the server and it along with all clients are connected to a D-Link DI-524 wireless router on a 192.160.0.0-100 IP range. DHCP is handled by the router and each client has a fixed IP tied to it's MAC address.  Our internet is cable modem with a fixed IP address and this along with ISP DNS has been entered into the WAN side of the DI-524 router.

We have a fully qualified domain name registed in NZ and an A record "ourservername.firstfruits.co.nz" pointing to our fixed (ISP) IP address and an MX record pointing to  "ourservername.firstfruits.co.nz".  Port forwarding for 25, 110 and 80 has been setup in the router.

Users and Computers have been added and mostly it's all running fine with a couple of exceptions...

Client computers nic's are set to automatically get IP and this works fine for internet access but they are unable to load companyweb (Intranet) unless the server IP address is entered manually into thier Preferred DNS server field on the nic.

In the past I have always checked the "Obtain DNS server address automatically" and found this to work for internal and external HTTP requests so am at a loss as to why it requires our servers IP in this case.

The other odd thing is that outgoing email to "some" recipients is getting delayed, I'm seeing it in the servers SMTP queue for up to 24hrs.

Any ideas what might be causing this?

Cheers
David
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DavidBurchett
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Hi,

I've since got round the delayed email by setting the server's SMTP connector to use my ISP's smart host but it would be good to know why I had delays when using DNS to route via this connector.

I guess this confirms there are issues with the way I've set up my DNS, I'll leave the question open in case anyone is able to help get this sorted. I'm sure that I should not have to enter theserver's IP into the Preferred DNS server field on each client.

Cheers
David
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beechy_
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hi there ...

about the 1st issue Client computers nic's are set to automatically get .... etc... you have reconfigure DHCP to set youe internal DNS as preferred then configure Internal DNS to forward unresolved quires to your ISP DNS.

and 2nd issue about email delays .. maybe it caused  by DNS problems, especially you mentioned that the delay when you send outbound emails., may to try to set your ISP DNS on external DNS on the SMTP connector


i hope that can help
Hi beechy and EL-SHIMY,

Many thanks for your input.

I have the router serving up the IP addresses as some devices here are not part of the server network in so far as they do not require any resourses from the server and have no way of being added into active directory.

Even if the server is down these devices still need to be online and this was the rationale for using the routers DHCP capabilities. I've seen this setup work in other installations but am unsure of how to set it up.

Thanks again
David
How often do you plan on your SBS being down?  You really should have DHCP running on the SBS.  Even if they require no other server resources they can still use it as their DHCP server.  Being a DHCP client has no requirement to be part of the Active Directory.  You can also set reservations in the DHCP scope on the SBS to assign addresses per client MAC address as you are doing with your router.  Also those devices won't just suddenly stop working if the SBS is down, they just won't get a new address if they happen to reboot whilst the SBS is down.  Really, you need to run DHCP on the SBS, this allows your clients to register their addresses in DNS when they log on or off, if you do things the 'SBS way', using the wizards etc. as it was intended to be used, you will save yourself a lot of time and effort in the long run.

To do so you will need to disable DHCP on the router first, if the SBS detects another DHCP server on the LAN 1. the connect to internet wizard will not run and 2. the DHCP service will stop.
Thanks beechy,

This is how it went...

1. Disabled the router for DHCP
2. Set the server NIC to fixed IP 192.168.0.1
3. Set default gateway to router fixed (LAN) IP address
4. Set the server nic preferred DNS to 192.168.0.1
5. Set the server nic alternate DNS to ISP's Preferred DNS server IP
6. Set my SMTP connector back to using DNS to route email
7 Ran the E&IC wizard
8. Set clients to automatically get IP and DNS

The results are:
1. Clients can no longer access companyweb
2. Client Outlook 2007 - A window pops up ("Connect to ourservername.firstfruits.local") asking for password (username already filled in) but won't accept when correct password is supplied.
3. Email is stuck in the queue again.

I had a look in the SBS services and see that DHCP is disabled so I'm going to reboot the router in case the sbs still thinks it's serving the IP's. Sending this now in case I loose conectivity to the internet and it gets to late (nearly 3am here).

Cheers
David

undo step 5 for a start

when supplying the username to outlook did you use the format internaldomainname\username
to be honest you are probably better off using your ISP's smarthost for outbound mail, it overcomes many anti spam requirements at large ISPs and mail providers that sending out via DNS may not satisfy.
if you run nslookup from a client and request companyweb what is returned??
Hi beechy,

I just looked and the wizard has already removed the ISP DNS server IP for me (point 5 above)

yes to username format, have since refresehd client nic and no connectivity so router dhcp must now be off but sbs not started yet

Cheers
David
ok i missed that, start the dhcp service on the sbs then reboot a client machine, check what ip configuration it gets and post it here, if it all looks ok check web browsing, companyweb, outlook etc
SBS DHCP started, SMTP connector back to ISP host and clients rebooted.

1. Clients getting IP's OK
2. No more queued email
3. Clients Outlook working again
4. Clients can new access Companyweb

Just need to clone MAC addresses and apply fixed IP's as it was set up in the router and we'll be back in business. Not sure where in the sbs setup to do that but I'l leave it until tomorrow now as it's getting quite late (early) over here.

Thanks for your help so far
David

Well done have a good night's sleep, i will find a link and post it here for you for tomorrow.
At the bottom of this article http://www.windowsnetworking.com/articles_tutorials/DHCP_Server_Windows_2003.html it explains how to configure reservations, which is Microsoft speak for assigning a specific MAC address a specific IP address.

Note you need to enter the MAC address without space or hyphens, just one long string of characters eg abcdef012345 for this to work
Hi beechy,

Thanks for the link, the article deals with full server 2003 and I have sbs version. I can't see a DHCP wizard at all but have drilled down through Computer management . Services and Applications to the DHCP section.

I think it will be straightforward to add my fixed IP devices but I am unsure how one goes about creating an entry for a device that sometimes uses wireless and sometimes hard wired connection. Creating two entries with all the same details (except MAC) might cause a conflict?

Can you also let me know if I set the forwarder correctly as in your comment above... "configure dns on the sbs with a forwarder to you isp's dns servers"? - I have my ISP's DNS server IP's entered in my servers DNS under Computer Management . Services and Applications . DNS . myservername . Forwarders. Hope that's correct?

One last thing... I had to manually set the routers fixed IP in Computer Management . Services and Applications . DHCP . Scope Options. 003 Router - I would have expected that to have been set when I entered it during the E&IC wizard setup. Maybe the wizard don"t always get it right?

Cheers
David

To be honest I was just referencing the last part of the article where it refers to reservations, not expecting you to follow the entire thing.  DHCP configuration is in Administrative Tools although you can access the same management tools through computer management as you've discovered.

You have to assign a different IP address to each network adapter of a device with multiple adapters.

You are correct about the forwarder.

The router IP should have been configured in DHCP by the CEICW.  It might be worth running through the wizard again tand then checking the DHCP options to make sure.
Hi beechy,

Thanks for that, the router did not seem to mind if a device used wirless or wired so will re think and maybe use machine names instead of IP's.

Anyway you've solved my issue so I'll close this off and award the points.

Thanks for your help.

David