glances – new way to look at contention

glances is like top/htop but little different. It shows you sort based on contention (smartly and automatically) unless you change that and hence if you just want to check what is biggest bottleneck in system, then head over to glances quickly. Here is quick description from dnf info command

 

Name : glances
Version : 2.11.1
Release : 2.fc28
Arch : noarch
Size : 3.2 M
Source : glances-2.11.1-2.fc28.src.rpm
Repo : @System
From repo : fedora
Summary : CLI curses based monitoring tool
URL : https://github.com/nicolargo/glances
License : GPLv3
Description : Glances is a CLI curses based monitoring tool for both GNU/Linux and BSD.
:
: Glances uses the PsUtil library to get information from your system.
:
: It is developed in Python.

vagrant box to libvirtd (QEMU) VM

Like ova images, you can use box images as well with Qemu. After all, both have the disk images, so here is the script to do that. Just put the script somewhere in your path and run with ova or box image name :

 

#!/bin/bash - 
#===============================================================================
#
#          FILE: ova2vm.sh
# 
#         USAGE: ./ova2vm.sh 
# 
#   DESCRIPTION: 
# 
#       OPTIONS: ---
#  REQUIREMENTS: ---
#          BUGS: ---
#         NOTES: ---
#        AUTHOR: Amit Agarwal (aka),
#  ORGANIZATION: Mobileum
#       CREATED: 12/28/2017 13:59
# Last modified: Sun Mar 11, 2018  12:01PM
#      REVISION:  ---
#===============================================================================

set -o nounset                              # Treat unset variables as an error
dest='/mnt/Backup/VM'
ORIG=${PWD}

if [[ $# == 0 ]]
then
    echo "You need to provide ova/vmdk filename"
    exit
fi
if [[ $1 == *ova || $1 == *box ]]
then
    tmp=$(mktemp -d /tmp/amitXXXXXXX)
    cd  $tmp
    tar xvf $ORIG/$1
    file=$(echo $PWD/*vmdk)
else
    file=$1
    echo "Not a OVA file"
fi
dfile="$dest/$(basename $file)"

read -p "Enter the name for VM :: " vmname
qemu-img convert $file $dfile -p -c -O qcow2
virt-install --disk $dfile --ram 512 \
    --virt-type kvm --vcpus 1 --name "$vmname" --import

Send history of current host to some other host over ssh

Sometimes I want to save the history of current host on another host. This is to ensure that I can use copy/paste on other host to run the commands. To this, I found a simple solution –

history| ssh <user>@<host> 'cat - > /tmp/history'

And on the new host, you can find the history in file “/tmp/history”, cool :). Now I can quick edit this file to create this as shell script as well if required. How cool is that.