libvirt users - Jul 2015 - Re: libvirt beginner needs to create and start VMs entirely on command line

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.

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
>

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<http://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<mailto: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<mailto:libvirt-users@redhat.com>
https://www.redhat.com/mailman/listinfo/libvirt-users

On 07/09/2015 07:57 PM, KARR, DAVID 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.
You will need for your VM:
- a storage
- CPU
- memory
- display (ex: vnc) or console

nice to have to:
- installation device (ex: mounted ISO) are network boot
- network (most time you need a network connection ;) )

I think reading the complete manpage for virt-install would be not to
bad. But some informations that I can give you befor:

you can connect virt-install, virsh, virt-viewer, virt-manager, ... over
ssh to your virtualistation host. My virtualisation host dont have any
graphics, i  have only a SSH connection and doing all over it. I use
virsh, virt-install and virtmanager. All works (tunneled) over SSH. For
this you only need to connect on the right way:
https://libvirt.org/remote.html
https://libvirt.org/uri.html

when you want to connect with for example virt-manager to your remote
libvirtd just write the right URI and you can connect only with an SSH
connection to it.

If you want to use virt-install and virsh, for virt-install there is a
good manual but for virsh I don't know a complete manual. But # virsh
help command   # should help to.

you need to describe how you want to connect to your vm. I don't know
the default which virt-install is taking but you can set it to vnc:
--graphics=vnc

When you don't have graphics where you are running virt-install then you
should add:
--noautoconsole

You can start virt-install on you local machine and just give the option:
--connect=driver[+transport]://[username@][hostname][:port]/[path]\[?extraparameters]

So I hope I could help and answer some questions.

Best Regards
Aaron