RHCSA Preparation Labs (EX200)

📦 Day 1: systemd Services & journalctl Logging

📌 Objectives

• Manage system services using systemctl (start, stop, enable, disable, mask, unmask).
• Analyze boot time performance using systemd-analyze.
• Filter and inspect system logs using journalctl.

Commands Executed

# Service Control & Boot Analysis
systemctl status httpd
systemctl start httpd
systemctl enable httpd 
systemctl is-enabled httpd
systemctl is-active httpd
systemd-analyze blame

# Log Filtering (RHCSA Core)
journalctl -u sshd
journalctl -b
journalctl -p err

Visual Verification

📦 Day 2: LVM Basics & Storage Management

📌 Objectives

• Create Physical Volumes (PV), Volume Groups (VG), and Logical Volumes (LV).
• Format LVs with ext4 and configure persistent mounting via /etc/fstab.
• Perform Live Expansion (lvextend).
• Clean up LVM components safely.

Commands Executed

# 1. Physical & Volume Group Creation
pvcreate /dev/nvme0n2
vgcreate test-vg /dev/nvme0n2

# 2. Logical Volume Creation & Formatting
lvcreate -L 2G -n test-lv test-vg
mkfs.ext4 /dev/test-vg/test-lv
mkdir /test-data
mount /dev/test-vg/test-lv /test-data

# 3. Expansion & Full Cleanup
lvextend -L 4G -r /dev/test-vg/test-lv
umount -l /test-data
lvremove -f /dev/test-vg/test-lv
vgremove test-vg
pvremove /dev/nvme0n2

Visual Verification

📦 Day 3: User & Group Management, Permissions & ACLs

📌 Objectives

• Perform local user account creation, group assignment, and password management.
• Manage group creation, renaming, and deletion.
• Configure directory ownership, special permissions (SGID), and ACLs.

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Task Breakdown & Commands

1. User Management & Primary Group Assignment: Created user1 with a home directory, verified its identity, created a primary group Security, and set the user's password.

   sudo useradd -m user1
   ls /home
   id user1
   sudo groupadd Security
   sudo usermod -g Security user1
   id user1
   sudo passwd user1
   

2. Group Operations: Demonstrated group creation, renaming (DevOps to Sec), and deleting redundant groups.

sudo groupadd DevOps
sudo groupmod -n Sec DevOps
sudo groupdel Sec

3. Directory Ownership & SGID Configuration: Created /data/project, assigned group ownership to devops, and applied the SGID bit (2770) so new files inherit the group identity.

sudo mkdir -p /data/project
sudo chown -R root:devops /data/project
sudo chmod 2770 /data/project

4. Access Control Lists (ACL): Configured granular read and execute permissions (r-x) for otheruser using setfacl.

sudo setfacl -m u:otheruser:rx /data/project
getfacl /data/project

Visual Verification

• User Management (useradd, usermod, passwd):

• Group Management (groupadd, groupmod, groupdel):

• SGID & ACLs Configuration (chmod 2770, setfacl):

📦 Day 4: Package Management using DNF

🎯 Objectives

• Master package search and detailed inspection using dnf.
• Install and verify packages (such as nginx) on RHEL.
• Identify package providers for specific configuration files using dnf provides.
• Remove packages safely using the dnf package manager.

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🛠️ Executed Commands & Operations

1. Package Search & Inspection

Search for nginx package details and configuration provider

dnf search nginx
dnf info nginx
dnf provides /etc/nginx/nginx.conf  

2. Package Installation & Verification

Install nginx web server package

sudo dnf install -y nginx

Verify installed package

dnf list installed | grep nginx

3. Package Removal

Remove package from the system

sudo dnf remove -y nginx

📸 Visual Verification

Day 05: Networking, Time Synchronization & Firewalld Configuration

1. System Identification & Environment

• Hostname: mohamed-server
• OS: Red Hat Enterprise Linux 10.0 (Coughlan)
• Kernel: Linux 6.12.0-55.9.1.el10_0.x86_64
• Hypervisor: VMware, Inc.

2. Network Configuration

• Interface Name: ens160
• IP Address: 192.168.1.100/24
• Subnet Mask: 255.255.255.0
• Broadcast Address: 192.168.1.255
• MAC Address: 00:0c:29:27:b1:2a

Commands Executed:

sudo nmcli con mod ens160 ipv4.addresses 192.168.1.100/24 ipv4.method manual
sudo nmcli con up ens160

3. Time Synchronization & System Time

Timezone Set: Africa/Algiers (Set via timedatectl) Time Daemon: chronyd installed and enabled via systemctl. NTP Verification: Verified active time synchronization using chronyc sources -v and chronyc tracking.

4. Firewall Configurations

Commands Executed

sudo firewall-cmd --add-service=ntp --permanent
sudo firewall-cmd --reload
sudo firewall-cmd --list-services

Verification Summary

1. Hostname Verification Snapshot

2. Network & IP Verification Snapshots

3. Time Synchronization Snapshots

4. Firewall Verification Snapshot

DAY06

RHCSA SELinux Practice: Custom Web Root & Non-Standard Port Configuration

🎯 Overview

This repository contains a step-by-step practical implementation for configuring a custom web server directory and non-standard HTTP port on Red Hat Enterprise Linux (RHEL) using SELinux policy management tools.

Objectives

-Set up a custom document root directory (/web/secure). -Reconfigure Apache (httpd) to run on a non-standard port (8282). -Apply persistent SELinux file context rules and network port labeling. -Enable user home directory web access via SELinux Booleans.

Commands Execution Summary

1.Create Web Content Directory & Sample File:

mkdir -p /web/secure
echo "RHCSA TEST PAGE" > /web/secure/index.html

2.Configure Persistent SELinux File Context :

semanage fcontext -a -t httpd_sys_content_t "/web/secure(/.*)?"
restorecon -Rv /web/secure

3. Update Apache Configuration : (/etc/httpd/conf/httpd.conf)

Change Listen 80 to Listen 8282. Update DocumentRoot and block to /web/secure.

4. Add Custom Port to SELinux Policy :

semanage port -a -t http_port_t -p tcp 8282

5. Enable SELinux Home Directory Label :

setsebool -P httpd_enable_homedirs on

6. Restart Service & Verification :

systemctl restart httpd
curl http://localhost:8282

Troubleshooting Notes

​Invalid Port Type Error: When executing semanage port, use http_port_t instead of httpd_port_t. ​File Context Application: Remember to execute restorecon after semanage fcontext to apply context labeling to existing files on disk.

Day07 : Firewalld Management: Port & Advanced Rich Rules Configuration

🎯 Objectives :

-Manage active zone configurations (public). -Allow standard web services (http) and non-standard custom ports (8282/tcp). -Implement Firewalld Rich Rules for conditional traffic control based on source IP addresses. -Persist and apply runtime firewall updates.

Commands Executed :

1.Standard service and custom port :

firewall-cmd --add-service=http --permanent
firewall-cmd --add-port=8282/tcp --permanent

2. HTTP drop rule configs :

firewall-cmd --add-rich-rule='rule family="ipv4" source address="10.0.0.5" service name="http" drop' --permanent

3. Advanced SSH traffic control :

irewall-cmd --add-rich-rule='rule family="ipv4" source address="192.168.1.55" service name="ssh" drop' --permanent
firewall-cmd --add-rich-rule='rule family="ipv4" source address="192.168.1.55" service name="ssh" accept' --permanent

4. Reload configs & Verification :

firewall-cmd --reload
firewall-cmd --list-all
firewall-cmd --list-rich-rules

Dayo08 SwapFiles in linux

1.Create Swap File

sudo dd if=/dev/zero of=/swapfile bs=1M count=1024
sudo chmod 600 /swapfile
sudo mkswap /swapfile
sudo swapon /swapfile
swapon --show

2.Persistent (fstab):

sudo nano /etc/fstab
# add the line:
/swapfile   none   swap   defaults   0   0

3.Delete Swap File

sudo swapoff -v /swapfile
sudo rm /swapfile
sudo nano /etc/fstab   # remove the /swapfile line

Day 09: Advanced Storage Implementation - VDO (Virtual Data Optimizer) on RHEL 10

📌 Overview

This lab demonstrates the deployment and configuration of Virtual Data Optimizer (VDO) via LVM on Red Hat Enterprise Linux 10 (RHEL 10). VDO provides inline data reduction through Zero-block Elimination, Deduplication, and Compression, optimizing storage utilization for enterprise workloads.

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🛠️ Environment & Technical Specifications

• OS: Red Hat Enterprise Linux 10 (RHEL 10)
• Physical Target Disk: /dev/nvme0n2 (10 GB)
• Volume Group (VG): vg-vdo
• Logical Volume (LV): lv-vdo
• Physical LV Allocation (-L): 5 GB
• Virtual LV Provisioning (-V): Filesystem:ystem:** ext4
• Mount Point: /data/vdo-storage

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🚀 Step-by-Step Implementation

Step 1: Storage Layer Initialization

Initialize the physical volume and create the dedicated LVM volume group on the NVMe drive:

pvcreate /dev/nvme0n2
vgcreate vg-vdo /dev/nvme0n2

Step 2: Native LVM VDO Provisioning Provision a VDO-enabled logical volume using LVM native Integration (--type vdo). A 20GB virtual volume is presented to the system backed by 5GB of physical allocation:

vcreate --type vdo -n lv-vdo -L 5G -V 20G vg-vdo

Step 3: Filesystem Formatting & Mount Setup Format the VDO logical volume with the ext4 filesystem and prepare the mount directory:

mkfs.ext4 /dev/vg-vdo/lv-vdo
mkdir -p /data/vdo-storage

Step 4: Persistent Mounting Configuration Configure /etc/fstab for persistent mounting across system reboots:

/dev/vg-vdo/lv-vdo /data/vdo-storage ext4 defaults 0 0

Apply systemd re-configuration and mount the volume:

systemctl daemon-reload
mount -a

📊 Verification & Status Monitoring Check Filesystem Usage Verify that the operating system reports the 20GB virtual capacity at /data/vdo-storage:

df -h /data/vdo-storage

Verify VDO Deduplication & Compression Metrics Inspect VDO pool operational statistics and space saving raèèètio:

vdostats --human-readable