Comments on SeanDaniel.com: Do I absolutely have to run DHCP on SBS 2008?

I followed you guide and when starting DHCP, windo...

2012-02-08T21:36:26.227-08:00

I followed you guide and when starting DHCP, windows states DHCP started sucessfully. I also stopped the services by disabling it and connect to internet fails...

If you want to run DHCP on your router, you have t...

2012-01-31T10:07:27.705-08:00

If you want to run DHCP on your router, you have to click it once to turn it on, and then immediately click it a second time to turn it off. Then run the CTIW and it will ignore the other DHCP server on the network and let you continue.

Sean, I am running into an identical issue as tes...

2012-01-30T10:57:39.578-08:00

Sean,

I am running into an identical issue as testing and Jim up above. I am trying to test SBS 2011 and run the CTIW after doing the steps you detailed above.
But after I click Start DHCP, I get prompted and asked if I want to start DHCP, I click yes. It tries to start and immediately shuts off. I see the error logged in Event Viewer.
But when I run the CTIW right after, the wizard keeps detecting that DHCP is still running on the firewall and quits when I click either Postpone or Continue.
Is there any workaround for SBS 2011?

I don't have any guidelines other than this po...

2012-01-23T16:22:48.914-08:00

I don't have any guidelines other than this post. You can give SBS 2011 a static IP and disable DHCP services using this post, and that should get you in a happy environment to be hosted.

Hello, I am trying to figure out how to install a ...

2012-01-22T17:51:48.431-08:00

Hello, I am trying to figure out how to install a SBS 2011 in a hosted environment. I was wondering if you have any suggestions. The scenario is simple, hosted company is giving me a Hyper-V with 24GB of RAM i7 4x2(HT)x2.66+ GHz with 2 TB of HD with one fixed IP. I would like to create my SBS 2011 and an application server (2k8r2) on this box. I am also thinking of getting one more for my 10 users virtual pcs (might be an over kill)… I know that the sbs2011 wants to take over the network (DHCP, DNS…) I have played around with a sbs2011 install on one of my boxes in the office and it really gave me a bad time with my router wanting to do the DHCP. If I do not have control over the hosts network… I can get additional IPs though and maybe create some sort of network configuration in the Hyper-V, not sure if that would work. Oh, I have absolutely no experience with Hyper-V. If there is some reading I can get out there for something that I am trying to do that you might know of, that would help also. Any suggestions would be greatly appreciated.

US VPN - there is nothing insecure on where you ru...

2012-01-16T11:37:39.210-08:00

US VPN - there is nothing insecure on where you run your DHCP server, the router or the SBS server, the security level is the same. SBS will most likely have a better DHCP server and is more robust, or have more features, that should be what your decision is made from

Larry T, Seems like you know too much to be dangerous on SBS! You can absolutely run DHCP on SBS, and it seems like you know how to configure it.

I think you should run DHCP on SBS, so that you...

2011-10-09T23:20:50.566-07:00

I think you should run DHCP on SBS, so that you're more secured.

Hi Sean, I appreciated the ideas and integration t...

2011-01-02T19:00:40.935-08:00

Hi Sean,
I appreciated the ideas and integration tips with the SonicWall devices as well.

I just wanted to raise a DHCP feature "DHCP Relay" which enables any router to forward DHCP requests on to a DHCP server.

It's very helpful as in the HealthSense case where three subnets on the wireless in addition to the inside LAN / SBS native subnet can be served by a single Windows DHCP server.

So, I have multiple subnets defined in my DHCP servers and for each subnet, I get all the pluses of creating reservations, etc as Sean mentioned.

Last, the equivalent of DHCP relay can most likely be found so your wireless network will just listen for DHCP requests and seamlessly to the DHCP client send them to the Windows DHCP server on SBS 2003 or SBS 2008.

CAVENT: I use "netsh dhcp server (ip address) dump (subnet) >servername-subnet-id-DHCP-SETTINGS.txt" so a batch job backups up the many DHCP servers I have on various dedicated Windows Server VMs. This approach works just as easy for SBS 2003/2008 environment with 10-75 users on the LAN and multiple wireless subnets.

When I'm not learning about SBS server migrations (hobby), I have 43 VLANs at work and in paricular, for each floor, I have a separate desktop DHCP server, printer DHCP server (used to boot VOIP devices as well) and a VOIP DHCP server. The desktop DHCP server handles all the wireless and VPN DHCP relay requests from our CIsco firewalls and MERU wireless controllers along with Radius server requests, etc. for authentication.

All the DHCP servers run on Windows Server 2003 R2 virtual machines (under VMware) and as I said, I use a single script using netsh dhcp server dump etc to create separate files for each subnet range that matches to the local IP subnet assigned to each VLAN.

I replicate that folder to all DHCP servers in case I have to have one or more take over for a problem DHCP server in a pinch.

Larry T [AKA VMSysProg]

Worked like a charm! Thanks for the info!

2010-10-15T23:23:52.263-07:00

Worked like a charm! Thanks for the info!

The key thing is just to ensure that DNS is config...

2009-12-08T12:16:21.878-08:00

The key thing is just to ensure that DNS is configured correctly.

What are the GOTCHA's when you disable DHCP an...

2009-12-01T15:18:05.100-08:00

What are the GOTCHA's when you disable DHCP and allow your router to provide that function?

I want my router to do DHCP so other network clients still function when the SBS is down.

However... I use VPN on my SBS. Will I be jacked with regard to VPN access if SBS doesnt control DHCP? And What other gotcha's should we be aware of?

Right, found the resolve here: http://blogs.techne...

2009-11-23T11:33:06.126-08:00

Right, found the resolve here:
http://blogs.technet.com/sbs/archive/2008/09/17/introducing-the-connect-to-the-internet-wizard-ctiw.aspx#3127305

Sorry, unfamiliar with blogger in general, not sure if I can drop a hyperlink in the comment or not, and couldn't find a way to simply edit my previous comment.

Resolve is basically to go into the SBS Console (Advanced), go to Network, Connectivity and click "Stop DHCP". Once stopped, you can run the CTIW w/out being prompted about disabling DHCP on your router. Then I disabled the DHCP notification as you described.

I did confirm that after clicking "Stop DHCP" and running the CTIW the DHCP service was set to disabled.

So far, all seems well.

Hi Sean, I'm having the same issue that "...

2009-11-23T11:03:33.565-08:00

Hi Sean,

I'm having the same issue that "testing" did above. Clicking "Start DHCP" starts the DHCP service just fine. It doesn't seem to care that there's another DHCP server running on the network. Even if I wait a few minutes and hit "refresh view" it never switches to "Disable DHCP". There's obviously more going on to how SBS 2008 detects whether DHCP is disabled or not, because disabling the service and setting it to not notify is insufficient, CTIW still complains and will not run.

Any thoughts on what may be causing this behavior? This is SBS 2k8 running on a new Dell R710. Relatively new. Given that both "testing" and I have run into the issue relatively recently, I'd also be inclined to suspect that it's an update that has changed this feature.

Any insights would be appreciated,

Thanks.

It should work just fine, if you open up DHCP mana...

2009-11-06T10:08:05.732-08:00

It should work just fine, if you open up DHCP management on the server it should load, if it doesn't, I would restart the DHCP services from services.msc.

Great write up, I'm sure it will help. I used...

2009-11-04T07:33:33.392-08:00

Great write up, I'm sure it will help.

I used dhcp server on many windows version. Unfortunatly, I've got problem running it on SBS2008. I configured it and now I cannot enter in the management interface. Is somebody having the same problem? I posted on http://www.petri.co.il/forums/showthread.php?p=186552
Thank you,
LF

Because this button keys of the state of the DHCP ...

2009-10-26T13:52:06.499-07:00

Because this button keys of the state of the DHCP server, you will have to click it twice.

Your router having DHCP on it tells the SBS service not to start. Thus the button says "Enable DHCP", which does start the DHCP service, and it will promptly shut down again, but click the button again which now says "Disable DHCP". At this point it will disable the DHCP service and set the flag so CTIW can continue while your router runs DHCP.

Do not set the server's IP address to dynamic, this is an unsupported scenario.

No Microsoft SW Updates will have broken this.

Hi there, I'm unable to make your workaround ...

2009-10-25T19:34:25.447-07:00

Hi there,

I'm unable to make your workaround work.

When i hit "Enable DHCP" button, it starts the DHCP service just fine.

I even tried removing the SBS' manual LAN IP and setting it to "Automatic" (ie, DHCP from my router) and it STILL turns DHCP on with no problem.

Does this tip no longer work due to Microsoft SW updates or something?

And obviously, the CTIW won't budge past this.

I'm integrating this box into a well oiled Mac network, so i don't wanna mess with my working DHCP setup.

Hey Jason, I think you are hitting a different is...

2009-10-19T13:44:30.832-07:00

Hey Jason, I think you are hitting a different issue. You want to make sure that all the firewalls between the WLAN and LAN are disabled. Sonicwall keeps the WLAN and LAN seperate by default (for guest access), you want to dis-allow guest access, and then add the firewall rules to allow all traffic to go from the WLAN to the LAN.

Then in the Sonicwall DHCP server, you want to set the Primary DNS server to be the SBS 2008 server's LAN IP address.

Then you'll want to make sure from a WLAN client that you can resolve the server name, domain.local name, and then server.domain.local name, they should all resolve.

That should fix your setup.

DHCP cannot pass out packets on a seperate subnet, as that's the design of DHCP, to be single subnet only. The only way to do this would be to have a wireless network card added to the server, which would drastically increase wireless traffic on that network, and you'd be putting SBS in an unsupported network configuration, which could introduce other concerns.

Hope that helps,
Sean

My client is running SBS 2008 with a SonicWALL NSA...

2009-10-19T11:52:44.290-07:00

My client is running SBS 2008 with a SonicWALL NSA 240. DHCP for the wired network is handled by SBS, with wireless being handled by the SonicWALL. We are using HealthSense nurse call devices on the wireless network and they get their addresses from the SonicWALL. The vendor is seeing some issues with addressing and has suggested serving DHCP from SBS 2008 for the wireless network.

Is there a way to have SBS 2008 DHCP server work in a VLAN environment, so its able to assign the correct IP scope to the correct VLAN. There are 3 VLANs in the network.

Jason

I'm confused in your question. This functiona...

2009-10-15T13:39:05.085-07:00

I'm confused in your question. This functionality disables DHCP on the SBS server so you don't see the errors about another DHCP server on your network so you can run a DHCP server.

You can simply do the trick again to enable DHCP to get it back to the SBS server. What are you trying to do?

I've tried to use this trick, but SBS doesn...

2009-10-15T13:01:27.100-07:00

I've tried to use this trick, but SBS doesn't warn me that there is another DHCP server on my network (there is).

I obviously have a static IP for the SBS.

Any other ways i can fake my way through to the next step?

All patches and updates are installed as of today.

yeah, that Sonicwall is a little trickier. What I...

2009-03-21T12:14:00.000-07:00

yeah, that Sonicwall is a little trickier. What I did (since I also had a sonicwall in my house, but it didn't cooperate with my xbox gaming past-time) was to turn off DHCP on the LAN (wired) network and let the SBS server do that, then leave DHCP on for the WLAN (Wireless) and change the primary DNS address that it hands out to be the SBS server's IP address on the LAN. You also have to change some firewall rules to allow all traffic to pass thorugh un-filtered between the WLAN and LAN. That will allow the DNS traffic to get through. The DHCP traffic won't go through because DHCP is local subnet traffic only, and you are crossing a NAT when you go from WLAN to LAN (or to WAN for that matter).

I hope that makes sense. Good luck Bill.

Thank you very much Sean!

I'll move forwa...

2009-03-21T11:37:00.000-07:00

Thank you very much Sean!

I'll move forward from there...and will likely be back when I setup SBS2008 with a SonicWall TZ; which, of course, separates wifi as you eluded to. Unless you just want to go ahead and answer that question now! :-)

-Bill-

If they are on the same subnet (ie. your router do...

2009-03-21T09:26:00.000-07:00

If they are on the same subnet (ie. your router doesn't put wifi addresses on a seperate subnet) then the router will behavce as a switch and allow the DHCP packets to get through to the wireless computers.

this is how I run my house.
Sean

Ahhh...getting closer now due to the great info in...

2009-03-20T23:05:00.000-07:00

Ahhh...getting closer now due to the great info in this article!

I'm setting up SBS2008 in a currently server-less environment, where the FIOS comes into the router / wireless router, all wired devices homerun back to the router, and wireless devices look to the wireless router for addresses. If I run DHCP from the server, and disable it on my router, how will internal wireless devices connect and get IP addresses?

I know, I know; that should be easy to answer...but for some reason I'm just not seeing it at the moment.

Help me out? :-)

Comments on SeanDaniel.com: Do I absolutely have to run DHCP on SBS 2008?

I followed you guide and when starting DHCP, windo...

If you want to run DHCP on your router, you have t...

Sean, I am running into an identical issue as tes...

I don't have any guidelines other than this po...

Hello, I am trying to figure out how to install a ...

US VPN - there is nothing insecure on where you ru...

I think you should run DHCP on SBS, so that you...

Hi Sean, I appreciated the ideas and integration t...

Worked like a charm! Thanks for the info!

The key thing is just to ensure that DNS is config...

What are the GOTCHA's when you disable DHCP an...

Right, found the resolve here: http://blogs.techne...

Hi Sean, I'm having the same issue that "...

It should work just fine, if you open up DHCP mana...

Great write up, I'm sure it will help. I used...

Because this button keys of the state of the DHCP ...

Hi there, I'm unable to make your workaround ...

Hey Jason, I think you are hitting a different is...

My client is running SBS 2008 with a SonicWALL NSA...

I'm confused in your question. This functiona...

I've tried to use this trick, but SBS doesn...

yeah, that Sonicwall is a little trickier. What I...

Thank you very much Sean! I'll move forwa...

If they are on the same subnet (ie. your router do...

Ahhh...getting closer now due to the great info in...

Thank you very much Sean!

I'll move forwa...