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We are a web dev shop and all use laptops and at the moment use static IP's. Each machine has one NIC but we need multiple IP's to deal with the multiple IIS Sites we have. The more machines / users we get the more confusing it is getting to figure out who has what and which IP's are free.

What I am trying to figure out is how people deal with all the IP's centrally when single NIC's need multiple IP's. As I understand it DHCP can not be configured to assign multiple IP's to a single NIC.

Do people use a tool / simple spreadsheet listing them all or something else?

Sorry if this is a little bit of an open question, I have tried to keep it as tight and focused as I can.


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Is there a reason you don't use virtual directories? – Nate Sep 21 '10 at 21:37
Or name-based virtual hosts? – Zoredache Sep 21 '10 at 21:45
This probably depends on the amount of IPs and machines on the network. If you're not dealing with dozens->hundreds of IPs a spreadsheet is probably fine. – Kyle Buser Sep 21 '10 at 22:20
We use IP's because "the boss said so". In all honesty that's how they set it up so that's the way it has continued. We put host values in the websites bindings and edit the hosts file for each dev machine. It could be related to how the VS2008 solution is setup, but not 100% sure on that one. We normally have 4/5 IP's per machine. – Jon Sep 22 '10 at 19:53

Sounds like a real mess! what you want to do is have just one DHCP server dishing out one IP address to all your laptops.

Then use name based virtual hosts. Put a nameserver on your lan. Since you're using IIS you're probably using microsoft DNS as well, so you can create another A record with a different name and make it point to the same IIS server. Now when you browse your website (whichever one it is) you can access different sites

e.g. site1.local site2.local site3.local

They all point to the same IP, but IIS (if configured with virtual hosts) will allow you to see a different web site.

Does that make sense to you?

On the other hand, if you're saying that each user has IIS running on their laptop and you're developing on the laptop which may also be removed from the LAN, then you can also make use of virtual hosting. You could just get individuals to edit the hosts file

Found in c:\windows\system32\drivers\etc (under windows 7 64bit).

You can just put site1 site2

That will also work. Therefore you don't need multiple IPs. DHCP is meant to make managing LAN IP's easier not harder! so if it's becoming hard then you're doing something wrong eh.

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Hi Matt, yep we could be going about this the wrong way! We do edit our hosts files so that each laptop can have point to their own machine. The more I read the more it seems we are not going about it correctly. My only guess is it could be related to the way the VS2008 solution is setup, if a website is not there when opened the solutions throws a fit. – Jon Sep 22 '10 at 19:57

I just use an Excel spreadsheet with the following columns:

Subnet | IP | Host | Purpose

If it's the devices "main" IP address (there is no thing as a "main" ip address really, but this is the one that appears on TCP/IP properties main sheet, not the additional IP addresses field) it gets coloured in green, and if it's an "Additional" IP address it gets coloured in orange.

Under Purpose, we put the internal DNS name that's mapped to that IP address. This does not just apply to hosts with multiple IP's, but to every machine on the network with a static IP address.

However: we only dish out additional IP addresses because we host a lot of staging sites that run SSL. If you're not running SSL then there's no reason to be assigning additional IP addresses just to host more sites, because you can use name-based hosts in IIS (Under "Bindings" in IIS7 and "IP Addresses" in IIS6/5) to host as many websites as you want under one IP address.

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Hi Farseeker, thanks, well explained. – Jon Sep 22 '10 at 19:58

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