How to detect virtualization 虚拟机检测

除了下面的方法外，mac地址也可以检测虚拟机。
Update: You may be interested in [[the perl module|perl-module-for-virtualization-detection]] implementing these tricks.

Frequently, our customers want to install our software in a virtual machine. This can be OK, but frequently they hit a CPU, memory, or IO limit caused by running in a constrained virtual environment. When this happens, we really like to know if they’re running under virtualization when we try to support them. Here’s some tricks to detect, from a shell, if the system is virtualized.

The first thing to check is dmesg. On a recently-booted system, checking the ‘dmesg’ command output may be sufficient. Otherwise, try “cat /var/log/dmesg” instead of “dmesg”

 

• VMWare:

   # dmesg | grep -i virtual VMware vmxnet virtual NIC driver   Vendor: VMware    Model: Virtual disk      Rev: 1.0 hda: VMware Virtual IDE CDROM Drive, ATAPI CD/DVD-ROM drive

• QEmu or KVM:If the “-cpu host” option has not been used, QEmu and KVM will identify themselves as:

   # dmesg | grep -i virtual CPU: AMD QEMU Virtual CPU version 0.9.1 stepping 03

  otherwise, the host’s CPU information will be used both in dmesg, or in /proc/cpuinfo.

  However, you should see something like:

   $ dmesg | grep -i virtual [    0.000000] Booting paravirtualized kernel on KVM

  on newer kernels that understand that they’re running under paravirtualization. (Thanks to René Pfeiffer for pointing this out)

• Microsoft VirtualPC:

   # dmesg | grep -i virtual hda: Virtual HD, ATA DISK drive hdc: Virtual CD, ATAPI CD/DVD-ROM drive

• Xen (thanks, wardi and others)

  # dmesg | grep -i xenXen virtual console successfully installed as tty1

• Virtuozzo

  # dmesg(returns no output)# cat /var/log/dmesg(returns no output)# ls -al /proc/vzveinfo  veinfo_redir  veredir  vestat  vzaquota  vzdata

On longer-running systems, you may need to grep /var/log/dmesg instead.

If that doesn’t produce anything useful, try using dmidecode to look at the BIOS information. Frequently, there will be at least one component identifying itself as virtualized:

• VMWare:

   # dmidecode | egrep -i 'manufacturer|product' Manufacturer: VMware, Inc. Product Name: VMware Virtual Platform

• Microsoft VirtualPC:

   # dmidecode | egrep -i 'manufacturer|product' Manufacturer: Microsoft Corporation Product Name: Virtual Machine

• QEMU or KVM:

   # dmidecode | egrep -i 'vendor' Vendor: QEMU

• Virtuozzo:

   # dmidecode /dev/mem: Permission denied

• Xen:

   # dmidecode | grep -i domU       Product Name: HVM domU

You should just examine the output of dmidecode directly rather than trying to grep as above, in case the output changes. QEMU, for example, doesn’t report the vendor in all versions.

Next, check disk devices for identification as virtualized:

• VMWare:

  # cat /proc/ide/hd*/modelVMware Virtual IDE CDROM Drive# cat /proc/scsi/scsiAttached devices:Host: scsi0 Channel: 00 Id: 00 Lun: 00  Vendor: VMware   Model: Virtual disk     Rev: 1.0  Type:   Direct-Access                    ANSI SCSI revision: 02

• Microsoft VirtualPC:

  # cat /proc/ide/hd*/modelVirtual HDVirtual CD

• QEMU, KVM, or Xen:

  # cat /proc/ide/hd*/modelQEMU HARDDISKQEMU DVD-ROM

• Virtuozzo:

  # ls -al /dev/vzfsb-----x--- 1 root root 0, 19 2009-04-06 15:04 /dev/vzfs