virtualbox.org

Hi All,

I have been using Virtual Box for a few months now on Linux hosts with XP Guests. - Works Great....

However, I am trying to use XP Hosts (at work) with an XP Guest, where the host is on the domain. I need the XP Guest to be able to see the XP Host and vice versa. My Idea (for some background knowledge) is to run an XP Guest with SQL2005 installed and then have my XP Host connect to the Sql2005 server.

I am a little confused on how I should set this up. I have tried a load of combinations with bridged-connections and NAT but all unsucessfull except for confusing myself.

I have the host on windows domain (192.168.17.114 - XP HOST) which also has a DHCP server on it. I would like to log into the XP Guest with my Domain user account and map a network drive back to my host PC for moving files between the guest and the host. I am quite happy to use port forwarding if needed to enable access to the Sql Server as well.

Should I be using NAT or Bridged or Host-interface? what exactly is the VirtualBox Host-Only Network used for ? do I need to set an address here for Virtual box to see the host network?

I would really appreciate if some one could point me in the right direction to achieving this. Sorry for being a complete Newb.... I am quite new to this Virtual Machine stuff and if I cant get this going the IT department are going to make me switch to M$ virtual PC - ARRRGH...

Thanks in advance for saving me from M$

Be careful about using the phrase "host interface". In VBox versions prior to 3.x, "Host Interface" network refers to the feature with 3.x now calls "Bridged Adapter". I assume that the name change was to differentiate it clearly from the newly implemented "Host Only Adapter" mode, which I also assume is what you are using.

As for the differences:
NAT is basically one way. The guest will receive replies to any messages it sends out, but it will not receive any unsolicited messages. So, you can't use this to implement an SQL server inside the guest because the guest wouldn't receive any of the requests.
BRIDGED is when the guest is essentially using the host NIC directly (albeit via virtualised hardware), but with a different MAC address. So, a guest should be able to do anything on the network that the host could with that NIC. This is the one to use for servers which are open to the internet/ethernet.
INTERNAL NETWORKING: if you have multiple guests running then they can communicate with each other, but not with the host or the internet (unless one of the guests has a second NIC and internet connection sharing set up).
HOST ONLY NETWORKING: Guests can talk to the host but not with each other (I may be wrong on that last bit). I find this mode very useful for sharing host folders with the guest, since it uses fixed IP addresses hence the name resolution time (and possible problems with) is eliminated from transactions.

Thanks for the reply. I will try out the bridged connection and yes sorry I am running version 3.0.6 r52128

Do I need to specify an IP address for the Guest Machine (as in the same as my Host Domain?) or does it use DHCP?


Update:
I have set the VM in VirtualBox to Bridged. I have then Disabled the adapter in my host called VirtualBox Host-Only Network. Next I booted the Guest XP machine and set the IP to DHCP on the Guest and I got a correct matching IP for the network that the Host is connected too. I then was able to ping both machines from each other (Host -> Guest, Guest-> Host) and following that managed to map a network drive between the two machines. - Again thanks for the clarification, I am not sure what happened last time but I was getting a very weird 10.0.2.15 address. Also using the "HOST ONLY NETWORKING" I was having conflicts with my existing DHCP. I think the NIC that was installed into my network connections was confusing me....

What is the purpose or a possible situation where you would use the "Virtualbox Host-only Network"?

Again, thanks for the Help....

I don't know why you disabled the "Host Only" network adapter, it should not have been causing any problems.

As to why you would use "Host Only", I answered that in my last message. It allows you to set up a network connection between host and guest without exposing the guest to the internet. It has the additional advantage that the host has a fixed IP addresses, which means you can map a network drive using a static IP address, which should make for faster access.

In addition, Host-Only is more like Internal Networking, only the Host is involved too. The description given by mpack about it is slightly off, the Guests CAN communicate with each other over that interface. This can be useful if you have several resources on the Host and Guests, like SQL on one, webserver on the other and the actual files on the Host.

I can't think of any reason why it will not work simply by setting the vm to use the bridged connection. If the guest is set to get its IP config automatically it should get an IP from DHCP, just as the host does. If it doesn't, manually configure it to have the same netmask, gateway and DNS address as the host. You could even join it to the domain. It should work just the same way as MS VPC would with the vm NIC linked to the physical NIC. I have run a setup like that under both VBox and VPC.

BillG wrote:I can't think of any reason why it will not work simply by setting the vm to use the bridged connection. If the guest is set to get its IP config automatically it should get an IP from DHCP, just as the host does. If it doesn't, manually configure it to have the same netmask, gateway and DNS address as the host. You could even join it to the domain. It should work just the same way as MS VPC would with the vm NIC linked to the physical NIC. I have run a setup like that under both VBox and VPC.

What if the OP does not have a router and is connected directly to the (cabel mode) or (DSL)? That would prevent the use of Bridged.

BillG wrote:I can't think of any reason why it will not work simply by setting the vm to use the bridged connection.

Unless things have changed recently, then a bridged connection only works if it is piggy-backed on a working host network connection, which not every host has. My development PC at work for example has no network connection (for security reasons). My laptop has a wireless connection, but of course that only works when it's within range of a wireless router I recognize. It's a while since I did the tests, but I seem to recall that (on Windows hosts anyway) if the host says the network connection is broken then VBox won't allow its use for a bridged connection either - even when your only interest is networking host<-->guest. On the other hand the "Host Only" connection always works, which makes it perfect for reliable shared folders, shared printer etc.

That's true, but in this case the original post states that the host has a private IP address from a DHCP server and is joined to a domain.

Way too much discussion over a simple problem.

I need the XP Guest to be able to see the XP Host and vice versa.

Use Host-Only for this to take place. If you need the guest to be on the Internet setup a second adapter and use NAT, or Bridged.

BillG wrote:That's true, but in this case the original post states that the host has a private IP address from a DHCP server and is joined to a domain.

Thats true too, and I answered him already in an earlier message. But the OP also asked what use anyone had for Host Only networking, so that's what the discussion became.

Thanks for all the replies....

I have followed the advice given earlier and the host and the guest are happily talking to each other via the bridged connection. I can also see the internet from the guest and all was well and merry... or so I thought.

It appears that virtual box is playing havoc with the domains DHCP. Whenever the virtual machine is running the Domains DHCP is being forced off the network and nothing else is able to join the network either. I have the virtual machine using a static IP address but still no luck. Basically every time I turn on the virtual machine I am causing chaos on our domain network.

Is it possible that Virtual box is internal DHCP is the problem?
Should I use two NICS like perrgy said?

Use Host-Only for this to take place. If you need the guest to be on the Internet setup a second adapter and use NAT, or Bridged.

What would likely to be causing this?

This is causing big issues with our IT and I am being forced to put M$ VPC on as the IT say "it just works", something I am trying to avoid........

There are several things that can cause this, and I can't say for sure unless I'm physically there to see what is happening on all the devices (DHCP server, switches, your machine, etc.). I can only speculate that it's perhaps some security in the switches that cause this, a duplicate MAC address entry in the DHCP or something else.

So, if you don't need anything additional from the VM with networking other than internet, use NAT and Host-Only.

Thanks....

Additionally.....

If I setup the virtual machine to use Host-Only the guest and the host CANNOT talk to each other. Both can see the static IP address I set the Host-Only Network to in the host machine, but the guest and the host are unable to communicate.

When I set the Host-Only network to obtain a IP address it comes back with a 192.168.56.101 address ?!? This address is not on our domain, we have a 192.168.17.1/255.255.255.0 addresses. would this address be coming from VB?

How do I setup the Host-Only so that the communication works between guest and host machine. I will worry about internet access later, I really only need the host and guest machines to talk and at present the only way I have managed this was with a bridged connection.

Are you sure you are using bridged networking? According to the VBox manual, the internal (VBox) DHCP server should be disabled when you are using bridged networking.

VBox User Manual wrote:The “dhcpserver” commands allow you to control the DHCP server that is built into VirtualBox. You may find this useful when using internal or host-only networking. (Theoretically, you can enable it for a bridged network as well, but that will likely cause conflicts with other DHCP servers in your physical network.)

You may want to have a read of the "VBoxManage dhcpserver" section of the manual. I can't help with much of this since not of the PC's I use VBox on are connected to a physical network, only to routers.