linux-admin-scripts

Practical Bash scripts for Linux system administration: monitoring, backups, maintenance, networking, and user management.
A curated collection of scripts that reflect real-world sysadmin tasks, following best practices and automation principles.

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Why

System administrators constantly repeat similar tasks: creating users, rotating logs, checking disk space, verifying connectivity, etc.
This repository centralizes those scripts into a reusable toolkit that is:

• Practical – tested in real environments (RHEL, Oracle Linux, CentOS, Ubuntu)
• Idempotent – safe to run multiple times without breaking things
• Secure – never stores secrets, encourages least privilege
• Documented – each script includes usage, exit codes, and prerequisites

Perfect as a reference for day-to-day Linux administration.

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Contents

• scripts/users/ – user & group management (create_user.sh, bulk_create_users.sh, …)
• scripts/monitoring/ – health checks & observability helpers (CPU, memory, disk, ports)
• scripts/maintenance/ – cleanup, patch helpers, log rotation
• scripts/network/ – connectivity and inventory checks
• scripts/backup/ – simple backup/restore helpers (rsync, tar/gzip)
• scripts/security/ – hardening snippets (SSH permissions, sudo checks)
• scripts/provisioning/ – environment setup for servers (e.g., setup_oda_env.sh)
• tests/ – smoke tests (Bats-compatible)

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Quick start

Run directly from the repo:

# lint (requires shellcheck)
make lint

# healthcheck: outputs CPU/memory/disk in JSON
scripts/monitoring/linux_healthcheck.sh

# disk usage alert (non-zero exit if thresholds exceeded)
THRESHOLD_WARN=80 THRESHOLD_CRIT=90 scripts/monitoring/disk_space_check.sh

# backup /etc into timestamped archive under /tmp/backups
SRC=/etc DEST=/tmp/backups scripts/backup/backup_dir_rsync.sh

# create a local user with safe defaults
sudo scripts/users/create_local_user.sh demo-user

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**Requirements**
- Bash 4+
- Linux environment...

**Contributing**
- Pull requests welcome!
- Follow these steps:
- Run make lint before committing.
- Document your script (header with usage, exit codes, notes).
- Keep it safe & idempotent.
- See CONTRIBUTING.md for details.

**Security**
- Never commit secrets, keys, or sensitive data
- Use placeholders (e.g., EXAMPLE.DOMAIN, 192.0.2.10) for demos
- Review SECURITY.md for disclosure policy