What you are trying to do is possible, but requires a little bit of funny command line scripting. Here are some scripts I wrote to boot UML machines. You will need to create /etc/uml/, a uml-net user group, and put each virtual machine as a user in its own home directory. Swap files should be named swap and root filesystems should be named root_fs. swap and root_fs should be owned by the user that the virtual machine runs as.
add the following to /etc/rc.local ------------------------------------------------------ # Copyright Jonas Meyer 2009. This script is licensed under the latest # version of the GPL, which is currently 3, and the full text of which # is available at fsf.org # Make it so UMLs can use tuntap chown root:uml-net /dev/net/tun # Make the host forward low level network packets from the UMLs to the local # subnet. This let's routers and stuff think that UMLs are real machines. echo 1 > /proc/sys/net/ipv4/ip_forward # This is a workaround for a bug where permenant entries disappear from the # arp table. Don't ask. I have no idea how this works. echo 512 > /proc/sys/net/ipv4/neigh/default/gc_thresh1 echo 1024 > /proc/sys/net/ipv4/neigh/default/gc_thresh2 echo 2048 > /proc/sys/net/ipv4/neigh/default/gc_thresh3 echo 1 > /proc/sys/net/ipv4/conf/eth0/proxy_arp # Finally, crank up each UML. Order is important, as some depend on others' # services. /etc/uml/machine1.sh sleep 15 /etc/uml/machine2.sh -------------------------------------------------------------- #!/bin/sh -e # Copyright Jonas Meyer 2009. This script is licensed under the latest # version of the GPL, which is currently 3, and the full text of which # is available at fsf.org # Set global variables HOST_ADAPTER="eth0" HOST_IP="xxx.xxx.xxx.xxx" GUEST_IP="xxx.xxx.xxx.xxy" USER="machine1" TAP="machine1tap" MAC="fe:fd:00:00:00:00" MEMORY="48M" # make a tap interface (fake ethernet link that the host and guest communicate via tunctl -u $USER -b -t $TAP ifconfig $TAP $HOST_IP up netmask 255.255.255.255 # tell the host how to talk to the uml route add -host $GUEST_IP dev $TAP # make the host forward low level ip packets from umls to local subnet # This lets routers and stuff know how to find the uml echo 1 > /proc/sys/net/ipv4/conf/$TAP/proxy_arp # now do it back the other way to the uml arp -Ds $GUEST_IP $HOST_ADAPTER pub # Crank up UMLs screen -d -m -S $USER su - $USER -c "cd /home/$USER ; /usr/local/bin/linux ubda=root_fs ubdb=swap eth0=tuntap,$TAP,$MAC mem=$MEMORY" ---------------------------------------------------------------- pull out the extra linebreaks added by email and you should be good to go. Jonas On Fri, 2009-08-21 at 00:13 +0100, andy baxter wrote: > hi, > > I have two virtual machines, dolphin and anthill, running on a single > real machine, whale. I am trying to set them both up to serve websites. > dolphin is for my personal stuff and anthill is for a site that I'm > doing with some other people - I want to be able to give them root > access to the vm but not to whale or dolphin. > > The problem I'm having is getting the networking set up right. I can > start either of the vms separately, and they start up OK, but when I > start them both together, the second one to start can't start its > network. I've tried two ways of doing it: > > - using a single tap device (tap0), with the IP 192.168.2.1, and dolphin > on 192.168.2.2, anthill on 192.168.2.3 > - using two tap devices (tap0=192.168.2.1 --> dolphin=192.168.2.2, > tap1=192.168.2.3 --> anthill=192.168.2.4) > > Neither of these seem to work. > > Before I try anything else, it would be good to know if what I'm trying > to do is possible in principle, or if there are limitations in the way > TUN/TAP works which I need to know about. What I really want is to have > a virtual network of VMs all on the same network with a single route > (tap device) to the host computer. The reason for this is that whale is > also serving as my network firewall, and it's awkward to define rules > for multiple interfaces in shorewall. > > Is this possible? > > Thanks, > > andy > > ------------------------------------------------------------------------------ > Let Crystal Reports handle the reporting - Free Crystal Reports 2008 30-Day > trial. Simplify your report design, integration and deployment - and focus on > what you do best, core application coding. Discover what's new with > Crystal Reports now. http://p.sf.net/sfu/bobj-july > _______________________________________________ > User-mode-linux-user mailing list > User-mode-linux-user@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/user-mode-linux-user ------------------------------------------------------------------------------ Let Crystal Reports handle the reporting - Free Crystal Reports 2008 30-Day trial. Simplify your report design, integration and deployment - and focus on what you do best, core application coding. Discover what's new with Crystal Reports now. http://p.sf.net/sfu/bobj-july _______________________________________________ User-mode-linux-user mailing list User-mode-linux-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/user-mode-linux-user
