We already knew how to [**check if your Linux OS is 32 bit or 64 bit**][1] and how to [**find if your Linux system is physical or virtual machine**][2]. Today, we are going to learn yet another useful topic – how to find if a CPU supports virtualization technology (VT) or not? This should be first thing you might want to verify before installing virtualization applications such as VirtualBox or VMWare workstation to run virtual machines on your Linux system. Now let us go and find out if your computer supports VT or not. Trust me, it is really easy!
### Find If A CPU Supports Virtualization Technology (VT)
We can check if the CPU supports VT in several methods. Here I present you four methods.
#### Method 1: Using “egrep” command
**Egrep** is one of the variant of [**Grep**][3] command which is used to search text files with regular expressions. For the purpose of this guide, we are going to grep **/cpu/procinfo/** file to find out if the CPU supports VT or not.
To find out if your CPU supports VT using egrep command, run:
```
$ egrep "(svm|vmx)" /proc/cpuinfo
```
**Sample output:**
You will get either **“vmx”** (Intel-VT technology) or **“svm”** (AMD-V support) in the output.
Since the output is very long, you may find it hard to find the words “vmx” or “svm” in the output. No worries! You can distinguish those terms with colors like below.
```
$ egrep --color -i "svm|vmx" /proc/cpuinfo
```
![][5]
If you don’t get any output, it means that your system doesn’t support virtualization.
Please note that these CPU flags (vmx or svm) in the cpuinfo means that your system will support VT. In some CPU models, the VT support might be disabled in the BIOS, by default. In such cases, you should check your BIOS settings to enable VT support.
For more details about grep/egrep command, refer the man pages.
```
$ man grep
```
#### Method 2 – Using “lscpu” command
The “lscpu” command is used to display the information about your CPU architecture. It gathers information from sysfs, /proc/cpuinfo file and displays the number of CPUs, threads, cores, sockets, and Non-Uniform Memory Access (NUMA) nodes of your host system.
To find out if the VT support is enabled or not, simply run:
```
$ lscpu
```
![][6]
For more details, check the man pages.
```
$ man lscpu
```
#### Method 3 – Using “Cpu-checker” utility
**Cpu-checker** is yet another useful utility to test your CPU for virtualization support. As far as I searched on the web, this utility is available for only Ubuntu-based systems. To install it, run:
```
$ sudo apt-get install cpu-checker
```
Once cpu-checker package is installed, run the following command to check whether VT support is enable or not:
```
$ sudo kvm-ok
```
If your CPU supports VT, you will get the following output:
```
INFO: /dev/kvm exists
KVM acceleration can be used
```
If your CPU doesn’t support VT, you will see an output something like below.
```
INFO: Your CPU does not support KVM extensions
KVM acceleration can NOT be used
```
#### Method 4 – Using “virt-host-validate ” tool
This tool is specifically for RHEL based distros like CentOS and Scientific Linux. The **libvirt-client** package provides **virt-host-validate** binary. So you need to install “libvert-client” package to use this tool.
```
$ sudo yum install libvirt-client
```
Now, run “virt-host-validate” command to find if VT is enabled or not in your RHEL-based systems.
```
$ sudo virt-host-validate
```
If you get **pass** for all results, your system supports VT.
```
QEMU: Checking for hardware virtualization : PASS
QEMU: Checking if device /dev/vhost-net exists : PASS
QEMU: Checking if device /dev/net/tun exists : PASS
QEMU: Checking for cgroup 'memory' controller support : PASS
QEMU: Checking for cgroup 'memory' controller mount-point : PASS
QEMU: Checking for cgroup 'cpu' controller support : PASS
QEMU: Checking for cgroup 'cpu' controller mount-point : PASS
QEMU: Checking for cgroup 'cpuacct' controller support : PASS
QEMU: Checking for cgroup 'cpuacct' controller mount-point : PASS
QEMU: Checking for cgroup 'cpuset' controller support : PASS
QEMU: Checking for cgroup 'cpuset' controller mount-point : PASS
QEMU: Checking for cgroup 'devices' controller support : PASS
QEMU: Checking for cgroup 'devices' controller mount-point : PASS
QEMU: Checking for cgroup 'blkio' controller support : PASS
QEMU: Checking for cgroup 'blkio' controller mount-point : PASS
QEMU: Checking for device assignment IOMMU support : PASS
LXC: Checking for Linux >= 2.6.26 : PASS
LXC: Checking for namespace ipc : PASS
LXC: Checking for namespace mnt : PASS
LXC: Checking for namespace pid : PASS
LXC: Checking for namespace uts : PASS
LXC: Checking for namespace net : PASS
LXC: Checking for namespace user : PASS
LXC: Checking for cgroup 'memory' controller support : PASS
LXC: Checking for cgroup 'memory' controller mount-point : PASS
LXC: Checking for cgroup 'cpu' controller support : PASS
LXC: Checking for cgroup 'cpu' controller mount-point : PASS
LXC: Checking for cgroup 'cpuacct' controller support : PASS
LXC: Checking for cgroup 'cpuacct' controller mount-point : PASS
LXC: Checking for cgroup 'cpuset' controller support : PASS
LXC: Checking for cgroup 'cpuset' controller mount-point : PASS
LXC: Checking for cgroup 'devices' controller support : PASS
LXC: Checking for cgroup 'devices' controller mount-point : PASS
LXC: Checking for cgroup 'blkio' controller support : PASS
LXC: Checking for cgroup 'blkio' controller mount-point : PASS
```
If your system doesn’t support VT, you will see an output like below.
```
QEMU: Checking for hardware virtualization : FAIL (Only emulated CPUs are available, performance will be significantly limited)
[...]
```
And, that’s all for now folks. In this guide, we have discussed various methods to find if a CPU supports VT or not. As you can see, it was very easy. Hope this was useful. More good stuffs to come. Stay tuned!
