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# Complete Optimized LVM Setup Guide for Dell Optiplex with Dual SSDs
## System Specifications
- Device: Dell Optiplex
- CPU: Intel Core i7-4790
- RAM: 32GB
- Storage:
- Drive 1 (sda): Samsung SSD 860 PRO 512GB (476.9G usable)
- Drive 2 (sdb): PNY CS900 120GB SSD (111.8G usable)
## 1. Partition Scheme and LVM Setup
### System Drive (sdb - PNY CS900 111.8GB):
- /dev/sdb1 - 1GB - /boot (standard partition, ext4)
- /dev/sdb2 - 1GB - /boot/efi (standard partition, FAT32)
- /dev/sdb3 - Rest of sdb (~109.8GB) - LVM Physical Volume
LVM setup on sdb:
Volume Group: vg_system
Logical Volumes:
- lv_root - 30GB - /
- lv_home - 25GB - /home
- lv_var - 15GB - /var
- lv_tmp - 5GB - /tmp
- lv_swap - 16GB - swap
- lv_snap - Rest of space - Reserved for snapshots
### Data Drive (sda - Samsung 860 PRO 476.9GB):
- /dev/sda1 - Entire disk - LVM Physical Volume
LVM setup on sda:
Volume Group: vg_data
Logical Volumes:
- lv_vms - 400GB - /vms (for storing virtual machines)
- lv_data - Rest of space (~76.9GB) - /data (for additional data and LVM practice)
All filesystems will use XFS except for swap and boot partitions.
## 2. Installation Process
1. Boot from Rocky Linux installation media.
2. In the installation wizard:
a. Select language and keyboard layout.
b. Set time zone.
c. In the Installation Destination section:
- Select both SSDs.
- Choose "Custom" partitioning.
- Create partitions and LVM setup as per the scheme above.
d. Set root password and create a non-root user.
e. Begin the installation.
3. After installation completes, reboot the system.
## 3. Post-Installation LVM Setup
After first boot, set up the data drive:
```bash
sudo pvcreate /dev/sda
sudo vgcreate vg_data /dev/sda
sudo lvcreate -L 400G -n lv_vms vg_data
sudo lvcreate -l 100%FREE -n lv_data vg_data
sudo mkfs.xfs /dev/vg_data/lv_vms
sudo mkfs.xfs /dev/vg_data/lv_data
sudo mkdir /vms /data
echo "/dev/vg_data/lv_vms /vms xfs defaults,discard 0 0" | sudo tee -a /etc/fstab
echo "/dev/vg_data/lv_data /data xfs defaults,discard 0 0" | sudo tee -a /etc/fstab
sudo mount -a
```
## 4. Initial OS Setup and Optimization
1. Update the system:
```bash
sudo dnf update -y
```
2. Install essential packages:
```bash
sudo dnf install -y vim tmux htop iftop iotop git wget curl
```
3. Configure firewall:
```bash
sudo systemctl enable firewalld
sudo systemctl start firewalld
sudo firewall-cmd --set-default-zone=public
sudo firewall-cmd --add-service=ssh --permanent
sudo firewall-cmd --reload
```
4. Secure SSH:
Edit `/etc/ssh/sshd_config`:
```bash
sudo vim /etc/ssh/sshd_config
```
Make these changes:
- Change `#PermitRootLogin yes` to `PermitRootLogin no`
- Set `PasswordAuthentication no` if using SSH keys
- Add `AllowUsers your_username` at the end of the file
Restart SSH service:
```bash
sudo systemctl restart sshd
```
5. Set up automatic security updates:
```bash
sudo dnf install dnf-automatic -y
sudo systemctl enable --now dnf-automatic.timer
```
6. Configure NTP for accurate system time:
```bash
sudo dnf install chrony -y
sudo systemctl enable --now chronyd
```
7. Optimize SSD performance:
Enable TRIM support:
```bash
sudo systemctl enable fstrim.timer
sudo systemctl start fstrim.timer
```
Add `discard` option to fstab for all SSD partitions:
```bash
sudo sed -i 's/defaults/defaults,discard/' /etc/fstab
```
Optimize I/O scheduler for SSDs:
```bash
echo 'ACTION=="add|change", KERNEL=="sd[ab]", ATTR{queue/rotational}=="0", ATTR{queue/scheduler}="mq-deadline"' | sudo tee /etc/udev/rules.d/60-schedulers.rules
```
8. Optimize system performance:
Edit `/etc/sysctl.conf`:
```bash
sudo vim /etc/sysctl.conf
```
Add these lines:
```
# Increase system file descriptor limit
fs.file-max = 100000
# Optimize network performance
net.core.somaxconn = 1024
net.core.netdev_max_backlog = 5000
net.core.rmem_max = 16777216
net.core.wmem_max = 16777216
net.ipv4.tcp_wmem = 4096 12582912 16777216
net.ipv4.tcp_rmem = 4096 12582912 16777216
net.ipv4.tcp_max_syn_backlog = 8096
net.ipv4.tcp_slow_start_after_idle = 0
net.ipv4.tcp_tw_reuse = 1
```
Apply changes:
```bash
sudo sysctl -p
```
9. Set up fail2ban to protect against brute force attacks:
```bash
sudo dnf install fail2ban -y
sudo systemctl enable --now fail2ban
sudo cp /etc/fail2ban/jail.conf /etc/fail2ban/jail.local
sudo sed -i 's/bantime = 10m/bantime = 1h/' /etc/fail2ban/jail.local
sudo sed -i 's/maxretry = 5/maxretry = 3/' /etc/fail2ban/jail.local
sudo systemctl restart fail2ban
```
10. Enable KVM nested virtualization for better VM performance:
```bash
echo "options kvm-intel nested=1" | sudo tee /etc/modprobe.d/kvm-intel.conf
```
11. Set up a basic backup script:
Create `/usr/local/bin/backup.sh`:
```bash
sudo tee /usr/local/bin/backup.sh > /dev/null << EOL
#!/bin/bash
BACKUP_DIR="/data/backups"
DIRS_TO_BACKUP=("/etc" "/home" "/var/log")
mkdir -p \$BACKUP_DIR
for dir in "\${DIRS_TO_BACKUP[@]}"; do
tar -czf \$BACKUP_DIR/\$(basename \$dir)-\$(date +%F).tar.gz \$dir
done
# Keep only the last 7 backups
find \$BACKUP_DIR -type f -mtime +7 -delete
EOL
sudo chmod +x /usr/local/bin/backup.sh
```
Set up a cron job to run it daily:
```bash
echo "0 2 * * * /usr/local/bin/backup.sh" | sudo tee -a /etc/crontab
```
12. Reboot to ensure all changes take effect:
```bash
sudo reboot
```
## 5. Verification and Management Commands
- Display LVM information:
```bash
sudo vgs # View Volume Groups
sudo lvs # View Logical Volumes
sudo pvs # View Physical Volumes
```
- Extend a Logical Volume:
```bash
sudo lvextend -L +10G /dev/vg_data/lv_data
sudo xfs_growfs /data
```
- Create a snapshot:
```bash
sudo lvcreate -L 5G -s -n lv_data_snapshot /dev/vg_data/lv_data
```
- Merge a snapshot:
```bash
sudo lvconvert --merge /dev/vg_data/lv_data_snapshot
```
- Check disk usage:
```bash
df -h
```
- Monitor system performance:
```bash
htop
```
- View current LVM layout:
```bash
sudo lvdisplay
sudo vgdisplay
```
## 6. Next Steps and Learning Opportunities
1. Practice creating and managing LVM snapshots on the lv_data volume.
2. Experiment with extending and reducing logical volume sizes.
3. Set up a KVM virtual machine in the /vms directory and practice VM management.
4. Learn about LVM striping and mirroring (for future multi-disk setups).
5. Explore LVM thin provisioning for efficient storage use in VM environments.
## Conclusion
This setup provides a robust, flexible, and optimized system for your Dell Optiplex with dual SSDs. The LVM configuration allows for easy management and expansion of storage. Remember to regularly update your system, monitor performance, and perform backups, especially before making significant changes to the LVM structure.
As you become more comfortable with LVM, explore advanced features and always test in a safe environment before applying changes to critical data.
---
# **Complete Rocky Linux Lab Setup: Virtualization, Automation, and Networking** # **Complete Rocky Linux Lab Setup: Virtualization, Automation, and Networking**
This guide provides a step-by-step process for setting up an advanced lab environment on Rocky Linux, including virtualization, automation, networking, security, and monitoring. It covers everything from system preparation to multi-VM setups using Vagrant and libvirt. This guide provides a step-by-step process for setting up an advanced lab environment on Rocky Linux, including virtualization, automation, networking, security, and monitoring. It covers everything from system preparation to multi-VM setups using Vagrant and libvirt.