ow do I determine if a port is in use under Linux or Unix-like system? How can I verify which ports are listening on Linux server? [click to continue…] Sysadmin because even developers need heroes!!!
am a new Linux and KVM user. How do I delete a VM guest with virsh command line on Linux operating system? How do I delete a virtual machine called vps42 on Ubuntu or CentOS Linux server? [click to continue…]
very serious security problem has been found in the Linux kernel. A 0-day local privilege escalation vulnerability has existed for eleven years since 2005. This bug affects all sort of of Android or Linux kernel to escalate privileges. Any user can become root in less than 5 seconds. The bug has existed since Linux kernel version 2.6.22+. How do I fix this problem? [click to continue…]
Before upgrading my virtual machine, I would like to make a snapshot. I want to revert a domain/VM to a snapshot if something goes wrong with my upgrade. Is there a command to create a snapshot of virtual machine (VM) while it is running? Does qemu-kvm support live snapshot creation?
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am getting the following error in my cron job log file /var/log/cron.log: Aug 22 01:59:01 server2 cron: Error: bad username; while reading /etc/cron.d/backups
I have job entry as follows to run a job at 00:50 every day for root user: 50 0 * * * /etc/cron.d/backups
How do I fix this problem on Linux or Unix-like system? [click to continue…]
ow do I create disk image using dd command? How do I perform disk cloning from a live Linux cd for backup or recovery purpose? [click to continue…]
‘m a new Linux system user. How do I check how long a process or pid has been running on my Ubuntu Linux server? [click to continue…]
have a cloud-based virtual machine running Ubuntu and CentOS Linux server. It may or may not be virtualized. How do I determine what kind of virtualization technology (VMWARE/ KVM/ XEN/ VirtualBox/ Container/ lxc/Hyper-V etc.) a Linux guest system running on? How do I find out the virtualization type of a CentOS 7 Linux VPS? [click to continue…]
am a new Linux server sysadmin. I need to delete POSTROUTING rule. How do I delete postrouting rule on Linux server? [click to continue…]
would like to compress a log file using gzip Unix command line utility, and I would also like to keep the original file. However, when I use the gzip my-app.log command, results in modifying my log file and renaming it my-app.log.gz. How do I force the gzip command to keep original file while maintaining the original file on Linux or Unix-like system? [click to continue…]