frequently-used-commands-in-linux.md

Install 'nslookup' in CentOS 7

sudo yum install bind-utils
nslookup gnutamil.blogspot.com

Shutdown linux machine

sudo shutdown -h now

Find RHEL version

cat /etc/redhat-release

SSH without password

ssh-copy-id -i ~/.ssh/id_rsa.pub [email protected]

# You can ssh without password now
ssh '[email protected]'

VM headless start

https://schier.co/blog/2013/03/13/start-virtualbox-vm-in-headless-mode.html

# Below command will list out all VMs
VBoxManage list vms

# You can start VM with UUID
VBoxManage startvm 6fb1108d-6a1f-45e4-8a45-ba71533bef3d --type headless

PowerOff VMs

VBoxManage controlvm 6fb1108d-6a1f-45e4-8a45-ba71533bef3d poweroff

LVM create

https://www.rootusers.com/how-to-increase-the-size-of-a-linux-lvm-by-adding-a-new-disk/

SELinux

# Check the status of SELinux
sudo sestatus
sudo setenforce 0

#Open
sudo vi /etc/sysconfig/selinux
# Change
SELINUX=disabled

Disable firewall in CentOS7

# Check status
sudo systemctl status firewalld

# Disable firewall
sudo systemctl disable firewalld

# Stop firewall
sudo systemctl stop firewalld

NFS installation in CentOS 7

https://www.itzgeek.com/how-tos/linux/centos-how-tos/how-to-setup-nfs-server-on-centos-7-rhel-7-fedora-22.html