transfer file Archive

Hot backup for KVM / libvirt / Xen

Overview We use Xen server on our development server and I decided, it’s time I start making full snapshots of my VM’s. So far we’ve done data backup only, mainly because of storage limitations. Since we got the new server, I have much more disk space now, so I would like to backup whole VM’s.

Leap second, Java and NTP leads to disaster – how to setup ntpd to avoid that

Like many other companies around the globe we also had some issues with last leap second. We couldn’t figure out why is our hadoop cluster acting strangely and using almost all CPU. After a while of browsing we found out, that the real cause of this was Java and leap second. As you may know

Moving logical volume (LVM) over network

Sometimes you come to an issue of moving raw volume from one server to another. Now this can be pretty complicated thing. You could make a snapshot of LV or make an image file, which you would copy then to another server, but that takes ages. When creating image you also need almost double the