Understanding QEMU

Since QEMU is the main tool I use in our virtual lab, it is crucial to know what qemu in general is and what are all the qemu options for? And I am no expert here, actully I ran some qemu images myself without honest understanding why am I providing this particular set of options and invoking qemu like that.

So to save myself some time in further searching for a good qemu guides and how-to’s I will keep here links about it I personally find useful

  1. Qemu page on an Arch linux wiki
  2. OpenSuse beautiful guide on Qemu



How to permanently change qemu’s qcow2 image?


Of course you heard of qemu. Its a hypervisor used by UNetLab and GNS3 to integrate virtual routers like Alcatel-Lucent’s 7750 SR, Junipers vMX and Cisco’s XRv. And it is well-known that those virtual routers come in the form of qemu disk images with an odd  qcow2 extension. But how can we alter those disc images if we need, for example, preconfigure and distribute an image with some interfaces configured, or got system name changed or even upload a license file?

I invite you to acquire this useful knowledge under the cut section.

ADD: I wrote another post on how to do this stuff automatically with libguestfs tools.