Re: [libvirt-users] libvirt beginner needs to create and start VMs entirely on command line

Jeff Tchang
2015-07-09T20:53:07Z

To see the boot console you need to have a VNC client and connect to it
once it is up.

For Mac OS I use the "Screen Sharing" application which can connect to
VNC
natively.
For Windows you can use something like tightvnc.

For SSH you need to make sure it is listening on the port.

--network is used to specify a libvirt network I believe.

On my example box it is in /var/lib/libvirt/network/default.xml

<!--
WARNING: THIS IS AN AUTO-GENERATED FILE. CHANGES TO IT ARE LIKELY TO BE
OVERWRITTEN AND LOST. Changes to this xml configuration should be made
using:
  virsh net-edit default
or other application using the libvirt API.
-->

<networkstatus>
  <class_id bitmap='0-2'/>
  <floor sum='0'/>
  <network>
    <name>default</name>
    <uuid>*****</uuid>
    <forward mode='nat'>
      <nat>
        <port start='1024' end='65535'/>
      </nat>
    </forward>
    <bridge name='virbr0' stp='on' delay='0'/>
    <mac address='****'/>
    <ip address='192.168.5.1' netmask='255.255.255.0'>
      <dhcp>
        <range start='192.168.5.100' end='192.168.5.254'/>
        <host mac='aa:bb:cc:dd:dd:dd' name='example-reserved'
ip='192.168.5.10'/>
      </dhcp>
    </ip>
  </network>
</networkstatus>

So basically you do --network default and then make sure the VM is
configured to do a DHCP out and it will get an address.

virsh net-edit default is the command you want to run.
There is also a command to view the networks that libvirt has.

On Thu, Jul 9, 2015 at 11:48 AM, KARR, DAVID <dk068x@att.com> wrote:

>  Thanks for replying.  Good info so far.
>
>
>
> After I start the VM, I’m going to need to see the boot console, and I’ll
> need to ssh into it with a hostname or IP.  What are some required steps
> for those needs?
>
>
>
> This VM is going to need to access a few associated networks.  I can see
> that the “—networks” option is part of the interface for configuring
> this.  What are some things I’ll have to do for this?
>
>
>
> *From:* Jeff Tchang [mailto:jeff.tchang@gmail.com]
> *Sent:* Thursday, July 09, 2015 11:21 AM
> *To:* KARR, DAVID
> *Cc:* libvirt-users@redhat.com
> *Subject:* Re: [libvirt-users] libvirt beginner needs to create and start
> VMs entirely on command line
>
>
>
> I actually find I do almost all my VM management inside the virsh command.
>
> If the VM appears to exist inside virsh but is in a shut off state then
> you should try to start it.
>
>
>
> VNC can also be SSH port forwarded (which I have done before).
>
>
>
> Not sure if this will help but this is the command I use to create VMs:
>
>
>
> virt-install \
>
>   --name example \
>
>   --vcpus=4 \
>
>   --disk /data/example,size=80 \
>
>   --ram 2048 \
>
>   --graphics vnc,password=**********,listen=0.0.0.0,port=15916 \
>
>   --accelerate \
>
>   --cdrom /var/kvm/ubuntu-14.04.1-server-amd64-autoinstall.iso \
>
>   --os-type=linux \
>
>   --noautoconsole \
>
>   --network network=default \
>
>   --boot cdrom,fd,hd,network,menu=off
>
>
>
> I also edit the XML file sometimes. Notice I have the autoinstall iso.
> Basically I went through and created a ks.cfg file after extracting the ISO
> file to a directory. Then I ran a command like this:
>
> mkisofs -D -r -V "auto install" -cache-inodes -J -l -b
> isolinux/isolinux.bin -c isolinux/boot.cat -no-emul-boot -boot-load-size
> 4 -boot-info-table -o /var/kvm/ubuntu-14.04.1-server-amd64-autoinstall.iso
> /root/serveriso
>
>
>
>
>
> On Thu, Jul 9, 2015 at 10:57 AM, KARR, DAVID <dk068x@att.com> wrote:
>
> I'm a beginner to libvirt and creating VMs, for that matter.  I have a
set
> of specifications for VMs I need to create and log into, but I have to
> create them on an Ubuntu box that I only have ssh access to.  I won't
have
> desktop GUI access, although I do have dynamic port forwarding, so I can
> access a browser GUI from my desktop.
>
> Reading through the libvirt info, I see numerous mentions about using VNC
> to do additional work, but I won't be able to use VNC (not allowed
within
> our firewall).
>
> I could use some advice on how to move forward with this.  I've started
at
> https://help.ubuntu.com/lts/serverguide/libvirt.html for initial
> information.
>
> I managed to create a disk image for my first VM, and I believe I created
> the first VM using an ISO (based on CentOS, I believe), but I'll
probably
> have to rebuild that, because I think I have to configure networks on the
> VM, which I didn't do on initial creation.  I was confused by the
initial
> results from "virt-install", because it seemed to hang after a
second or
> two (I posted this SO question about this:
>
http://stackoverflow.com/questions/31302871/trouble-using-virt-install-on-ubuntu-to-create-vm-just-hangs-after-displaying
> ).  The reply from this makes it seem like it was trying to present a GUI
> for next steps, but I of course never saw that.  The VM appears to exist,
> but in a "shut off" state.
>
> _______________________________________________
> libvirt-users mailing list
> libvirt-users@redhat.com
> https://www.redhat.com/mailman/listinfo/libvirt-users
>
>
>
> _______________________________________________
> libvirt-users mailing list
> libvirt-users@redhat.com
> https://www.redhat.com/mailman/listinfo/libvirt-users
>