Category: Administration / Server

GNU Linux Debian 10/11/Ubuntu – kvm-qemu virtualization host – guest auto resize screen – disk bench Windows 7 64Bit vm guest (only 32Bit works) – “Unable to init server: Could not connect: Connection refused” – wtf esxi has no clone button

first off the praise: kvm-qemu is a high performance nicely scriptable virtualization system if it works, it can do pretty things 🙂 IN CONTRAST TO iESXI SH** WARE CLONING A VM IS A EASY AS: virt-clone –original debian12 –name debian12-clone […]

GNU Linux How To – kvm qemu – start – clone (multiple disks) – snapshot – restore-revert – delete – shutdown all vms – start all vms with keyword in name – snapshot all vms – add remove disks

how to setup kvm on Debian: hostnamectl; # tested on Static hostname: lenovo Operating System: Debian GNU/Linux 10 (buster) Kernel: Linux 4.19.0-17-amd64 Architecture: x86-64 hostnamectl; # also on Operating System: Debian GNU/Linux 12 (bookworm) Kernel: Linux 6.1.0-17-amd64 # with virsh […]

Zehntausende Mail-Server wegen Exchange-Lücke gehackt – Cloud oder Klaut – Security Newsletter

scroll down to ENGLISH “Zehntausende Mail-Server wegen Exchange-Lücke gehackt.  Wegen einer vor wenigen Tagen bekanntgewordenen Sicherheitslücke sind laut US-Medienberichten Zehntausende E-Mail-Server von Unternehmen, Behörden und Bildungseinrichtungen Opfer von Hacker-Attacken geworden. “Deutsche Unternehmen sind im internationalen Vergleich besonders stark von dieser […]

phpBB – Profile Avatar Picture 6KBytes size limit

… because one also cares about beauty… a default avatar picture is not an option… but phpBB has a very strict 6KBytes max file size limit for Profile Avatar Pictures…  which is almost impossible to reach with format.jpg or format.png […]

GNU Linux Bash – script for troubleshoot long term reliability (ping) and bandwidth (speed) benchmark-test – testing network internet connection uplink connectivity and reliability

this script is for cront-job regular measurement of the available (download) bandwidth, by downloading a 100MByte dd crated ( testfile created like this (creditz): head -c 100m /dev/zero | openssl enc -aes-128-cbc -pass pass:”$(head -c 20 /dev/urandom | base64)” > […]

GNU Linux Debian 10/11/Ubuntu – how to install kvm virtualization (qemu) – basic virsh commands – kvm cheat sheed – howto workaround virt-manager “emulator may not have search permissions for the path”

BACKGROUND INFO: how does kvm use qemu? KVM (Kernel-based Virtual Machine) is a virtualization solution for Linux on x86 hardware. It allows running multiple virtual machines (VMs) on a GNU Linux host by leveraging hardware virtualization extensions such as Intel […]