Motivation

This page has linux commands which I found useful and worth practicing frequently to help myself.

mahendran@ubuntu-22.04:~$ iwgetid
wlp2s0    ESSID:"MYWIRELESS"

Firewall commands

root@ubuntu-22.04:~# ufw enable
Command may disrupt existing ssh connections. Proceed with operation (y|n)? y
Firewall is active and enabled on system startup
root@ubuntu-22.04:~# ufw status
Status: active

To                         Action      From
--                         ------      ----
22/tcp                     ALLOW       Anywhere
3389/tcp                   ALLOW       Anywhere
22/tcp (v6)                ALLOW       Anywhere (v6)
3389/tcp (v6)              ALLOW       Anywhere (v6)

Knowing Linux Distribution

root@ubuntu-22.04:~$ uname -a
Linux automation-mini-2 5.15.0-58-generic #64-Ubuntu SMP Thu Jan 5 11:43:13 UTC 2023 x86_64 x86_64 x86_64 GNU/Linux
root@ubuntu-22.04:~$ cat /etc/os-release
PRETTY_NAME="Ubuntu 22.04.1 LTS"
NAME="Ubuntu"
VERSION_ID="22.04"
VERSION="22.04.1 LTS (Jammy Jellyfish)"
VERSION_CODENAME=jammy
ID=ubuntu
ID_LIKE=debian
HOME_URL="https://www.ubuntu.com/"
SUPPORT_URL="https://help.ubuntu.com/"
BUG_REPORT_URL="https://bugs.launchpad.net/ubuntu/"
PRIVACY_POLICY_URL="https://www.ubuntu.com/legal/terms-and-policies/privacy-policy"
UBUNTU_CODENAME=jammy
root@ubuntu-22.04:~$

root@ubuntu-22.04:~# lsb_release -a
No LSB modules are available.
Distributor ID:	Ubuntu
Description:	Ubuntu 22.04.1 LTS
Release:	22.04
Codename:	jammy

Display - Session - Desktop

ls /usr/bin/*-session

Using sed

At times we may not have the luxury of the GUI editor or VI editor to make small changes. If sed command available, we could use it

sed -i  's/find-string/replace-all/g' file.txt