Daily Linux Server Management

System Health Check

System Resources

Running Processes

Check System Resources

Monitor CPU, memory, and disk usage:

# Check memory usage
free -h
# Check disk usage
df -h
# Check CPU usage (interactive)
top
# Alternative to top
htop

Monitor Running Processes

Identify resource-intensive processes:

# Show processes sorted by CPU usage
ps aux --sort=-%cpu | head -10
# Show processes sorted by memory usage
ps aux --sort=-%mem | head -10
# Real-time process monitoring
top
# Find processes by name
pgrep -l nginx

Tip: Set up monitoring tools like Nagios, Zabbix, or Prometheus for automated health checks.

Security Monitoring

Check for Unauthorized Access

Review authentication logs and open connections:

# Check failed login attempts
grep "authentication failure" /var/log/auth.log
# Check successful logins
grep "Accepted password" /var/log/auth.log
# Check current connections
netstat -tunap
ss -tunap
# Check sudo commands
grep sudo /var/log/auth.log

Firewall Status

# Check UFW status
ufw status
# Check iptables rules
iptables -L -n -v
# Check open ports
netstat -tuln
ss -tuln

Important: Regularly review security logs and investigate any suspicious activity.

Service Management

Check Critical Services

Ensure essential services are running:

# Check service status systemctl status nginx
systemctl status mysql
systemctl status apache2
# List all running services
systemctl list-units --type=service --state=running
# Check if service is enabled on boot
systemctl is-enabled nginx

Service Management Commands

# Restart a servicebr> systemctl restart nginx
# Stop a servicebr>
systemctl stop nginx
# Start a servicebr>
systemctl start nginx
# Enable service on bootbr>
systemctl enable nginx
# Reload service configuration
systemctl reload nginx

Note: Use reload instead of restart when possible to avoid downtime.

Backup Verification

Check Backup Status

Ensure backups are running successfully:

# Check backup logs
tail -n 20 /var/log/backup.log
# Verify backup file integrity
sha256sum /backup/server-backup.tar.gz
# Check backup disk space
df -h /backup
# List recent backups
ls -la /backup

Test Restoration Process

Periodically verify backups can be restored:

# Extract test file from backup
tar -tzf /backup/server-backup.tar.gz | head -10
# Test restore to temporary location
mkdir /tmp/restore-test
tar -xzf /backup/server-backup.tar.gz -C /tmp/restore-test --strip-components=1 ./important-file.txt

Warning: Backups are useless if they can't be restored. Test regularly!

Log Management

Review System Logs

Check for errors and warnings:

# Check system messages
tail -n 50 /var/log/syslog
# Check authentication logs
tail -n 50 /var/log/auth.log
# Check application logs
tail -n 50 /var/log/nginx/error.log
tail -n 50 /var/log/mysql/error.log
# Search for errors in logs
grep -i error /var/log/syslog | tail -n 20

Log Rotation

Ensure logs are being rotated properly:

# Check logrotate status logrotate --debug /etc/logrotate.conf
# Force log rotation
logrotate -f /etc/logrotate.conf
# Check disk usage of logs
du -sh /var/log/
# Find large log files
find /var/log -type f -size +100M

Tip: Set up log aggregation with tools like ELK Stack or Graylog for better log management.

Daily Checklist

Essential Daily Tasks

Check system resource usage
Review security logs
Verify backup completion
Check critical services
Review application logs
Check disk space
Update package lists
Check for security updates

Completion: 0%

Weekly Tasks

Apply security updates
Clean up temporary files
Review user accounts
Verify firewall rules
Test backup restoration

Package Management

Update Package Lists

# Ubuntu/Debian apt update
# CentOS/RHEL
yum check-update
# Fedora
dnf check-update

Check for Updates

# Ubuntu/Debian
apt list --upgradable
# CentOS/RHEL
yum list updates
# Fedora
dnf list updates

Security Updates

# Ubuntu/Debian (security updates only)
unattended-upgrade --dry-run
# Check for security updates
apt list --upgradable | grep -i security

Note: Test updates in a staging environment before applying to production.

Interactive Terminal

user@server:~$ # Welcome to the Linux server management guide
Select a command from below to simulate output

Note: This is a simulation. No actual commands are being executed.