CentOS – nixCraft

How to shutdown / reboot the remote Linux server from the CLI

August 7, 2017in CentOS, Debian / Ubuntu, Linux, RedHat and Friends, Suse last updated August 7, 2017

I am a new Linux sysadmin. How do I remotely shutdown or reboot the server from the CLI?

How to add new brick to replicated GlusterFS volume on Linux

July 25, 2017July 26, 2017in CentOS, Debian / Ubuntu, Linux, RedHat and Friends last updated July 26, 2017

I have a three server replicated volume setup (scalable network filesystem for cloud and VMs). I need to add one more server. How do I add a new a new brick to an existing replicated volume on a Debian or Ubuntu/CentOS Linux?

How to test the network speed/throughput between two Linux servers

July 25, 2017July 25, 2017in CentOS, Debian / Ubuntu, Linux last updated July 25, 2017

I have setup total four servers in cloud based data center. They run either CentOS or Ubuntu Linux. I need to make sure clustered file system performance is reasonable as my servers shared with other users. How do I check the speed between the two Linux servers using command line options for private LAN/VLAN?

How to upgrade LXD VMs powered by Ubuntu/Debian or CentOS Linux

July 11, 2017in BASH Shell, CentOS, Debian / Ubuntu, Linux, Linux Containers (LXC) last updated July 11, 2017

I run over 10+ LXD VMs powered by CentOS Linux 7 and Debian/Ubuntu Linux. How do I upgrade all VMs automatically or on demand using Ansible tool?

How to use or specify multiple IP addresses in iptables source or destination on Linux

June 29, 2017in CentOS, Debian / Ubuntu, Iptables, Linux, RedHat and Friends, Suse last updated June 29, 2017

I need to specific multiple IP address in iptables using Linux script. How do I create a rule that uses multiple source or destination IP addresses ?

How to install latest kernel on CentOS Linux 7 using yum command

June 25, 2017June 25, 2017in CentOS, Linux, Package Management last updated June 25, 2017

I am a new CentOS Linux 7 user who runs it on my Laptop. I liked the operating system. Is there is a way to run latest/stable Linux kernel on a CentOS Linux version 7?

How To Patch and Protect Linux Kernel Stack Clash Vulnerability CVE-2017-1000364 [ 19/June/2017 ]

June 20, 2017June 20, 2017in CentOS, Debian / Ubuntu, Linux, RedHat and Friends, Security, Suse last updated June 20, 2017

A very serious security problem has been found in the Linux kernel called “The Stack Clash.” It can be exploited by attackers to corrupt memory and execute arbitrary code. An attacker could leverage this with another vulnerability to execute arbitrary code and gain administrative/root account privileges. How do I fix this problem on Linux?