Linux for Cloud & DevOps Engineers - Hands-on!!

Explore the Linux file hierarchy structure and the filesystem hierarchy standard, from the root directory to /bin, /etc, /home, /usr, /var, /boot, and /dev, with root user access.

Explore the linux file hierarchy, from /lib and /bin to /sbin and /usr, including /opt for add-on apps and /proc as a virtual filesystem for process info.

Explore basic Linux commands by copying and moving files, preserving permissions with -p, renaming with mv, and recursively copying directories, using ls -ltr and cat to verify contents.

Create and manage users with useradd, assign uids and groups, set comments and shells, and review /etc/passwd, /etc/shadow, and home directories to understand passwords and aging.

Create groups and users on Linux systems with groupadd and useradd, as root, assigning a primary and supplementary group, and setting home directories, uids, shells, and passwords.

Create a user with a primary group and a supplementary group using useradd and the -G flag, then verify with id and learn to lock and unlock with passwd.

Learn to modify Linux user accounts with the usermod command, including appending comments, changing home directories, setting primary groups, locking and unlocking accounts, and switching shells.

Explore the /etc/shadow file, where encrypted password data and password aging policies are stored. Learn how fields, password changes, minimum and maximum days, warnings, inactive and expire affect user accounts.

Explore the initialization files in a user's home directory, including .bash_profile, .bashrc, and .bash_logout, and system-wide /etc/profile. Learn how login shells versus interactive non-login shells determine which file runs.

Create a user named jay, log in, and watch how initialization files run during login to set and export the path via .bash_profile and .bashrc.

Learn how .bash_profile and .bashrc control login and interactive non-login shells and how to set PATH to run scripts from any location using a practical path lookup example.

Discover how linux permissions govern access to files and directories by owner, group, and others, with read, write, and execute permissions and examples using ls -l.

Learn to read Linux file attributes with ls -l, where the first dash marks a file and D marks a directory, and interpret owner, group, and others permissions (read/write).

Explore how to change file or directory permissions using chmod in absolute (numeric) and symbolic modes, including numeric codes, symbolic representations, and operators for user, group, and others.

Log into an Amazon Linux server, create users and groups, assign group membership, switch users, and manage file and directory permissions with chmod.

Explore Linux group management and file permissions in a hands-on lab on Amazon Linux, creating a Linux group, assigning users, and using chmod to control access.

Practice linux permissions by creating and running a bash script, and use chmod to grant read, write, and execute rights for user, group, and others.

Create a directory named oradb, view its owner, group, and permissions with ls -ltr, and set 755 to grant read and execute access for others.

Learn to change file and directory ownership with the chown command, including switching owner and primary group as root, and applying recursive changes with the -R option.

Practice symbolic mode with chmod to change file and directory permissions using plus minus and equal operators for user, group, and others, and learn to add, remove, or overwrite permissions.

Explains vCPU limit exceeded during instance launches, showing a 32 vCPU cap per account for t2.micro, how to request a limit adjustment, and a 31-versus-32 instance test.

Identify AWS instance launch issues, including region limits, insufficient capacity, and immediate termination causes, and apply resolutions like increasing per-region limits and diagnosing with state-transition reasons.

Troubleshoot common ssh login issues across jump, oradb, and application servers by fixing private key permissions with chmod 400, using the correct Ubuntu or ec2-user, and adjusting inbound rules.

Learn to launch and configure an ec2 instance in the aws console, selecting region, ami, instance type, vpc, public ip, security groups, storage, and key pair.

Create and download a key pair to access your AWS instance. The private key enables SSH for Linux AMIs, while Windows requires the private key to obtain the login password.

Connect to your instances using putty and ssh -i with a private key. Generate a ppk from your key and access from Windows or Linux servers.

Launch two Linux instances, reuse a security group and an existing key pair, then ssh from webserver to webserver1 using the .pem key and the EC2 user to verify IPs.

Enable termination protection to guard against accidental termination, since it is off by default. Terminating an instance deletes its root EBS volume by default.

Learn how termination protection affects EC2 shutdown behavior by enabling protection on two instances; one stops while the other terminates when shut down from the OS, with exam-style question.

Learn how security groups act as firewalls for inbound and outbound traffic. Create and attach them to EC2 instances, define inbound rules like ssh and http, and apply changes immediately.

Learn how Amazon EBS provides persistent block storage for EC2 instances, enabling root and additional volumes for OS or databases, with gp2, io1, st1, sc1, and magnetic standard types.

practice managing ebs volumes by attaching root and additional disks to instances, observe volumes in availability zone, then modify size and types (gp2, st1, magnetic) and note deletion behavior.

Learn to create, attach, format, and mount EBS volumes, take and restore snapshots for backup and recovery, and even change volume types across availability zones.

Explore the difference between snapshots and AMIs, how snapshots back up volumes stored in S3 with incremental backups, and how AMIs boot new servers.

Encrypt your root volume by copying an encrypted snapshot to build an encrypted AMI and launch instances with encrypted root, a capability now available at installation time.

Back up an EC2 instance by snapshotting the root volume (/dev/sda1) in its availability zone, then restore by creating a volume from the snapshot, attach it, and start the instance.

Identify the root volume (the os disk) and its instance id, then use the modify volume action to increase the linux root disk from 10 gb to 15 gb.

Learn to view EC2 instance metadata from the command line using curl, retrieving details such as instance id, instance type, public and private IPs, DNS, security groups, and keys.

Explore managing services on a RHL 8 box with systemctl, including status, start, stop, enable, and disable, and examine unit files in /usr/lib/systemd/system for sshd and rsyslog.

Learn how systemd targets replace runlevels, booting into graphical or multi-user modes, and use systemctl to inspect dependencies and units.

Discover how to manage services with systemctl by distinguishing restart from reload, observing pid changes, and reloading configurations without downtime. Learn masking and unmasking to prevent service conflicts.

Explore how systemd replaces sysvinit and speeds boot times with parallel tasks. Learn to navigate unit configurations and use journal ctl to view logs and boot events.

Explore AWS Systems Manager, a unified interface to view and automate tasks. Patch Windows and Linux, inventory software, and group resources like EC2, S3, and RDS for security and compliance.

Install the AWS Systems Manager (SSM) agent on all EC2 and on-premises servers to enable communication with Systems Manager, with pre-installed options on certain AMIs and manual installs for others.

Configure two Amazon Linux 2 EC2 instances with SSM agent, attach an SSM EC2 role, and view them as managed instances in Systems Manager.

Learn to define and apply AWS tags with key and value pairs, and create tag-based resource groups to manage instances by environment and department.

Learn to use AWS Systems Manager Run Command to remotely manage instances, install software, run scripts, and capture logs with SSM documents.

Learn to create and run AWS Systems Manager documents in EC2 to configure Apache on Linux, using run shell script, Patch Manager, and CloudWatch outputs.

Learn how AWS Systems Manager Inventory provides visibility into your EC2 and on premises computing environment, showing installed software and patches on managed instances.

Configure patch manager using predefined baselines to patch webserver1 manually, with optional scheduling, and verify Linux and Windows patching steps against the Amazon Linux 2 default baseline.

Create a custom patch baseline for Amazon Linux 2 with critical patches auto approved immediately and bug fix patches auto approved after 14 days, and set it as default.

Tag web server 2 with batch group amazon linux, attach it to a custom amazon linux patch baseline, and configure patching to install security patches.

Master AWS Systems Manager Session Manager to securely access EC2, on-prem, and VMs via browser or CLI, using IAM controls and CloudWatch logging, no inbound ports or SSH keys.

Discover how AWS Systems Manager parameter store provides secure, hierarchical storage for configuration data and secrets, enabling encrypted passwords and values to be retrieved in scripts and run commands.

Create a parameter store entry to securely hold Sverma's Windows password, then run an SSM script to retrieve the password and reset Sverma's account, verifying login.

Learn to create and retrieve parameter store entries using AWS SSM put parameter and AWS SSM get parameter, including a string parameter and a secure string with decryption.

Showcases resetting the Windows administrator password on an AWS EC2 instance using AWS Systems Manager and EC2 Rescue for Windows, then retrieving the new password from parameter store.

Reach the last lecture of this course module and apply what you learned. Share doubts or suggestions via the question-answer form or ping the instructor.