Contact us: support@pscs.co.uk
Contact us: support@pscs.co.uk

vDHCP FAQ

Do I have to install vDHCP on a specific computer?

No, you can install vDHCP on any Windows 95, NT4 or later computer on your network.
You should have only one computer running vDHCP on each TCP/IP subnet you have (in small networks, you will generally have a single subnet).

vDHCP uses very little processing power, so it will run happily on a computer which is doing other things.

Which versions of Windows will vDHCP work on?

vDHCP was written for Windows 95 & 2000 in the days when small businesses and home users didn't have routers, so did not have a local DHCP server. It will run on later versions of Windows (including Windows 8 & Server 2012), but there are limitations in the later versions, because of differences in the architecture and security features of these later versions

In Windows Vista and later, vDHCP will not show 'live' windows when running as a service. There will actually be two copies of vDHCP running, one which is the service and has no user-interface, and one which is displaying the settings and is not actually providing a DHCP service, so will not show what is going on. If you run vDHCP as an application, rather than as a service, then it will be OK.

The problem running vDHCP as a service happens because Windows Vista and later do not properly support 'Interactive Services' any more - vDHCP was a single program which ran as a service and had a user interface, and this is no longer allowed by Microsoft - we would have to create a separate program for the user interface which communicates with the main vDHCP service. This would be a big task, and because we sell very few copies of vDHCP nowadays since most people are happy with the DHCP in their routers or other appliances, this is not something which we are planning to do.

Do I have to set a specific TCP/IP address on the vDHCP computer?

The vDHCP is the only computer on your network where you must explicitly specify an IP address.

You don't have to set a specific IP address, but we recommend that you specify an address in one of the accepted ranges for private networks, such as a number in the range 192.168.xxx.yyy (where xxx is 0 to 255 and yyy is 1 to 254), and set the subnet mask to 255.255.255.0

Do I have to tell the client computers how to contact vDHCP?

No, simply tell the client computers that their IP address is 'Server Assigned'.

The client computers will use a TCP/IP 'broadcast' to contact vDHCP, so it doesn't need to know where vDHCP is running.

Does vDHCP remember active leases between sessions?

Yes, as long as vDHCP is closed down properly between sessions.

Can I run Intranet servers (such as VPOP3) on a network managed by vDHCP?

Yes. You will need to set a fixed IP address for the Intranet server. See the next section for instructions on how to do that.

Can I assign fixed IP addresses to some computers on my network?

Yes. There are two options for this:

  1. Assign the IP addresses as normal within the other computer and set an exclusion in vDHCP so that it doesn't assign that IP address to any other computer.
  2. Set up a reservation in vDHCP so that it will automatically assign a certain IP address to a specific named computer.

How many client PCs can a single vDHCP server manage?

As many as can be supported by the TCP/IP subnet which vDHCP is running on.

Can vDHCP manage multiple subnets if it is run on a multi-homed computer?

No, vDHCP can only manage a single subnet. If you have multiple subnets you should run a copy of vDHCP on a computer on each subnet.