Shell Script Library

Performs a full system update on Debian/Ubuntu or RHEL/CentOS systems, including package cache refresh, upgrades, and optional reboot.

Finds and removes log files older than a configurable number of days from specified directories. Supports dry-run mode.

Monitors disk usage on all mounted filesystems and sends an email alert when usage exceeds a configurable threshold.

Checks current memory and swap usage, alerting when consumption exceeds configurable thresholds. Includes top memory-consuming processes.

Creates a compressed tar archive of a directory with a timestamp in the filename. Supports retention-based cleanup of old backups.

Dumps a MySQL or PostgreSQL database to a compressed file with timestamp. Supports all databases or a specific one.

Mirrors a local or remote directory using rsync with bandwidth limiting, exclude patterns, and optional SSH key authentication.

Implements a GFS (Grandfather-Father-Son) backup rotation strategy, keeping daily, weekly, and monthly backups with configurable retention.

Checks if a systemd service is running and restarts it if stopped. Logs events and sends email notifications on failures.

Monitors specified TCP ports on local or remote hosts and alerts when a port becomes unreachable.

Logs CPU and memory usage at regular intervals to a CSV file for historical analysis and trend monitoring.

Checks HTTP status codes and response times for a list of URLs. Alerts on non-200 responses or slow page loads.

Parses fail2ban logs to show ban/unban statistics, top offending IPs, and most targeted jails.

Scans auth logs for failed SSH login attempts, identifies brute-force patterns, and optionally blocks offending IPs.

Computes SHA-256 checksums for files in specified directories and compares against a stored baseline to detect unauthorized changes.

Checks SSL certificate expiration dates for a list of domains and alerts when certificates are nearing expiry.

Tests network connectivity to multiple hosts using ping, DNS resolution, and optional HTTP checks.

Performs batch DNS lookups for multiple domains, showing A, AAAA, MX, NS, and TXT records in a formatted report.

Scans a host for open TCP ports using bash built-in /dev/tcp (no external tools needed) or nmap if available.

Monitors real-time network bandwidth usage per interface, showing RX/TX rates updated every second.

Creates multiple Linux users from a CSV file with configurable shell, groups, and home directory settings.

Checks all local user accounts for upcoming password expiration and sends reminders to users or administrators.

Identifies user accounts that have not logged in for a specified number of days and optionally disables them.

Removes unused Docker images, stopped containers, dangling volumes, and unused networks to reclaim disk space.

Checks the health status, resource usage, and restart count of all running Docker containers.

Backs up Docker named volumes to compressed tar archives using a temporary container mount.

A deployment script template with pre/post hooks, rollback support, health checks, and notification integration.

Manages blue-green deployments by toggling between two identical environments with zero-downtime switching via nginx.

Generates and installs logrotate configuration files for application logs with customizable rotation policies.