Creating a FreeBSD 10 guest in KVM on a CentOS 7 Host
Continuing from my last post on installing KVM on CentOS 7, we'll look into installing a non-linux Operating System on CentOS 7 inside KVM. In this example I'll install FreeBSD 10.
Before we install any guest we need to get the list of supported guests - to get that list type:
virt-install --os-variant list
The output is too long to include here, but in the output we can see: freebsd8 which is what we're going to use.
Since I've assigned most HDD space under /home, I'll add a Linux user first and add him to the wheel group so he can be a sudoer and use that space:
useradd lampros -G wheel
In order to make the user a sudoer, we'll run visudo and comment out this line:
%wheel ALL=(ALL) NOPASSWD: ALL
Make sure this line is commented out:
##%wheel ALL=(ALL) ALL
grep wheel /etc/sudoers
Your output should look like this:
## Allows people in group wheel to run all commands ##%wheel ALL=(ALL) ALL %wheel ALL=(ALL) NOPASSWD: ALL
Now become that user:
su - lampros
Now we're going to need the ISO for the OS - download it with curl: (It's 622MB so it might take a while!)
curl -O ftp://ftp.freebsd.org/pub/FreeBSD/releases/amd64/amd64/ISO-IMAGES/10.0/FreeBSD-10.0-RELEASE-amd64-disc1.iso
Note that we downloaded the AMD64 version if FreeBSD - that will work since our host supports the VT extensions.
Now I save the following script to /home/lampros/create-kvm.sh
#!/bin/sh NAME= MEMORYMB= NUMCORES= OSVARIANT= ISOFILENAME= #if you've followed my previous post NIC needs to be bridge0 NIC=bridge0 DISKFILENAME=/home/lampros/freebsd10.img DISKSIZEGB=30 virt-install -n $NAME -r $MEMORYMB --vcpus=$NUMCORES --os-variant=$OSVARIANT --accelerate -v -c $ISOFILENAME -w bridge:$NIC --vnc --disk path=$DISKFILENAME,size=$DISKSIZEGB
After I fill in the variables with the options I need (amount of memory, number of cores, ISO filename and OS variant) the completed script now looks like this:
#!/bin/sh NAME=freebsd MEMORYMB=512 NUMCORES=1 OSVARIANT=freebsd8 ISOFILENAME=/home/lampros/FreeBSD-10.0-RELEASE-amd64-disc1.iso #if you've followed my previous post NIC needs to be bridge0 NIC=bridge0 DISKFILENAME=/home/lampros/freebsd10.img DISKSIZEGB=30 virt-install -n $NAME -r $MEMORYMB --vcpus=$NUMCORES --os-variant=$OSVARIANT --accelerate -v -c $ISOFILENAME -w bridge:$NIC --vnc --disk path=$DISKFILENAME,size=$DISKSIZEGB
Make the script executable:
chmod +x /home/lampros/create-kvm.sh
Run it with:
I got an error:
./create-kvm.sh Starting install... Creating storage file freebsd10.img | 30 GB 00:00:00 ERROR failed to retrieve file descriptor for interface: Permission denied Domain installation does not appear to have been successful. If it was, you can restart your domain by running: virsh --connect qemu:///session start freebsd otherwise, please restart your installation.
If you get the above check if SELinux is Enforcing or Permissive - check with the getenforce command:
The output I got is:
Set to permissive:
sudo setenforce Permissive
Change it permanently by editing the /etc/selinux/config file and making sure that the line:
is changed to:
you can do this by running:
sudo sed -i 's/SELINUX=enforcing/SELINUX=permissive/' /etc/selinux/config
Then you also need to edit the qemu.conf file, this should be under: /etc/libvirt/qemu.conf
#clear_emulator_capabilities = 1
clear_emulator_capabilities = 0
#user = "root"
user = "root"
#group = "root"
group = "root"
then uncomment this entire block:
#cgroup_device_acl = [ # "/dev/null", "/dev/full", "/dev/zero", # "/dev/random", "/dev/urandom", # "/dev/ptmx", "/dev/kvm", "/dev/kqemu", # "/dev/rtc","/dev/hpet", "/dev/vfio/vfio" #]
should now look like:
cgroup_device_acl = [ "/dev/null", "/dev/full", "/dev/zero", "/dev/random", "/dev/urandom", "/dev/ptmx", "/dev/kvm", "/dev/kqemu", "/dev/rtc","/dev/hpet", "/dev/vfio/vfio" ]
Make sure to exit and save Then restart the libvirtd service so that the changes take effect:
sudo service libvirtd restart
Run the script again:
and you should get:
Starting install... Creating domain... | 0 B 00:00:00 WARNING Unable to connect to graphical console: virt-viewer not installed. Please install the 'virt-viewer' package. Domain installation still in progress. You can reconnect to the console to complete the installation process.
KVM automatically starts up a VNC session - if you want to connect to it you'll need a tunnel as it's only listening to local (127.0.0.1) connections:
sudo netstat -ntlp | grep qemu-kvm
The output I got was:
tcp 0 0 127.0.0.1:5900 0.0.0.0:* LISTEN 8720/qemu-kvm
View active VMs:
sudo virsh list --all
In my case I get this output:
sudo virsh list --all Id Name State ---------------------------------------------------- 2 freebsd running
Destroy/stop a VM: (does not delete any files!)
sudo virsh destroy 2
Delete a VM: (permanently deletes files!)
sudo virsh undefine freebsd
To connect from Windows Using VNC you'll first need to establish an SSH tunnel - I do this with cygwin like this:
ssh -f email@example.com -L 5900:127.0.0.1:5900 -N
To check if the port is open, on the Windows side you can check with: (Note, this will not work in cygwin, but it will in Windows Command shell or PowerShell)
netstat -na | find "5900"
The output I got was:
TCP 127.0.0.1:5900 0.0.0.0:0 LISTENING TCP [::1]:5900 [::]:0 LISTENING
Now on Windows connect using something like TightVNC - since we're using an SSH tunnel set the remote host to 127.0.0.1
Now go ahead with a regular FreeBSD installation!
Sample output from VNC from Windows using TightVNC:
Once the installation is done the system will be shut down - check it's state with:
sudo virsh list --all
You should get something like:
Id Name State ---------------------------------------------------- - freebsd shut off
Start it up:
suvo virsh start freebsd
Check that it started:
sudo virsh list --all Id Name State ---------------------------------------------------- 3 freebsd running
That covers the basics of installing a new operating system inside KVM.