.bashrc, .bash_profile, PATH on AMI

Updated 20-Sep-2023

On a new Amazon Linux AMI installation, there is a useful ec2-user account configured. However, in order to make it more useful, there is a need to edit some .bashrc files, as well as create a new user for sftp and scp, as those will produce errors using login scripts that we will set for ec2-user.

First off, know that .bashrc is the best thing to use since it functions when using sudo su and executes every time, vs. .bash_profile which (I think) does not.

Second, both the ec2-user and root need .bashrc configurations, and my preference is that the first has sudo su invoked and runs right into root.

Third, the sftp/scp user will need sudo rights added to the cloud-init file.

Steps to Adjust Login Environments

• Edit .bashrc files for ec2-user and root
• Create new user (for sftp/scp), grant rights, and deal with access keys

.bashrc for ec2-user

nano /home/ec2-user/.bashrc

Use this file

# .bashrc
# Source global definitions
if [ -f /etc/bashrc ]; then
        . /etc/bashrc
fi
# User specific aliases and functions
alias rm='rm -i'
alias cp='cp -i'
alias mv='mv -i'
alias lx='ls -la --color=auto'
alias rx='rm -rf'
alias ban='fail2ban-client set apache-badbots banip'
# Set the interrupt keystroke to ctrl-e
stty sane
stty intr ^E
# Pathing
PATH=$PATH:$HOME/bin:~/.local/bin:/usr/local/bin
export PATH
export EDITOR=nano
clear
echo ""
echo "************************************************"
echo "  NEW LOGIN PROCESSED - WELCOME TO server, $USER"
echo "************************************************"
echo ""
sudo su

.bashrc for root

nano /root/.bashrc

Use this file

# .bashrc
# Source global definitions
if [ -f /etc/bashrc ]; then
        . /etc/bashrc
fi
# User specific aliases and functions
alias rm='rm -i'
alias cp='cp -i'
alias mv='mv -i'
alias lx='ls -la --color=auto'
alias rx='rm -rf'
alias ban='fail2ban-client set apache-badbots banip'
PATH=$PATH:$HOME/bin:~/.local/bin:/usr/local/bin
export PATH
export EDITOR=nano
cd /root/temp
clear
echo ""
echo "************************************************"
echo "  NEW LOGIN PROCESSED - WELCOME TO server, $USER"
echo "************************************************"
echo ""
htop

Create New User and Grant Rights

something missing here

Grant SUDO Rights

nano /etc/sudoers.d/cloud-init

duplicate the ec2-user rights for the new user

Adjust PATH

Edit the PATH in ~/.bash_profile

nano /root/.bash_profile

Use the following:

# .bash_profile
# Get the aliases and functions
if [ -f ~/.bashrc ]; then
        . ~/.bashrc
fi
# User specific environment and startup programs
PATH=$PATH:$HOME/bin:~/.local/bin:/usr/local/bin

Then load that profile

source ~/.bash_profile

Also add some helpful shortcuts lx and rx

nano /etc/profile

add to end of file:

alias lx='ls -la --color=auto'
alias rx='rm -rf'

User and SSH Cert

• Download, move, and rename cert

chmod 400 ~/.ssh/key.pem
ssh -v -i ~/.ssh/key.pem [email protected]
sudo su
yum -y update
useradd newuser
passwd newuser
usermod -aG wheel newuser
su - newuser
mkdir .ssh
chmod 700 .ssh
exit
cp /home/ec2-user/.ssh/authorized_keys /home/newuser/.ssh/authorized_keys
chown newuser:newuser /home/newuser/.ssh/authorized_keys
nano /etc/sudoers.d/cloud-init

replace ec2-user with newuser