Modernize and harden the cheatsheets repository

.github/ISSUE_TEMPLATE/content-correction.yml

@@ -0,0 +1,40 @@
+name: Content correction
+description: Report an inaccurate, obsolete, unsafe, or unclear command or explanation
+title: "[Correction]: "
+labels:
+  - documentation
+body:
+  - type: input
+    id: file
+    attributes:
+      label: File
+      description: Which cheat sheet needs correction?
+      placeholder: docker.md
+    validations:
+      required: true
+
+  - type: textarea
+    id: problem
+    attributes:
+      label: Problem
+      description: Explain what is inaccurate, obsolete, unsafe, or unclear.
+    validations:
+      required: true
+
+  - type: input
+    id: platform
+    attributes:
+      label: Platform and version
+      description: Include the product, operating system, and version when relevant.
+
+  - type: textarea
+    id: correction
+    attributes:
+      label: Suggested correction
+      description: Provide corrected wording or commands when possible.
+
+  - type: textarea
+    id: references
+    attributes:
+      label: Official references
+      description: Link the relevant vendor, project, or standards documentation.

.github/workflows/docs-quality.yml

@@ -0,0 +1,100 @@
+name: Documentation quality
+
+on:
+  pull_request:
+  push:
+    branches:
+      - main
+  workflow_dispatch:
+
+permissions:
+  contents: read
+
+jobs:
+  markdown-structure:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Check out repository
+        uses: actions/checkout@v4
+
+      - name: Validate maintained Markdown structure
+        shell: bash
+        run: |
+          python - <<'PY'
+          from pathlib import Path
+          import re
+          import sys
+
+          files = [
+              "README.md",
+              "CONTRIBUTING.md",
+              "STYLE_GUIDE.md",
+              "arista.md",
+              "azure.md",
+              "cisco.md",
+              "docker.md",
+              "gcloud.md",
+              "iptables.md",
+              "kubernetes.md",
+              "rest-api.md",
+              "terraform.md",
+          ]
+
+          errors = []
+          for filename in files:
+              path = Path(filename)
+              if not path.is_file():
+                  errors.append(f"{filename}: file is missing")
+                  continue
+
+              text = path.read_text(encoding="utf-8")
+              if not text.strip():
+                  errors.append(f"{filename}: file is empty")
+                  continue
+
+              first_content_line = next(
+                  (line for line in text.splitlines() if line.strip()),
+                  "",
+              )
+              if not first_content_line.startswith("# "):
+                  errors.append(f"{filename}: first content line must be an H1")
+              if "\x00" in text:
+                  errors.append(f"{filename}: NUL byte found")
+
+              for number, line in enumerate(text.splitlines(), start=1):
+                  if re.search(r"\[[^\]]*\]\(\s*\)", line):
+                      errors.append(f"{filename}:{number}: empty Markdown link")
+
+          if errors:
+              print("\n".join(errors))
+              sys.exit(1)
+
+          print(f"Validated {len(files)} maintained Markdown files.")
+          PY
+
+  links:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Check out repository
+        uses: actions/checkout@v4
+
+      - name: Check maintained documentation links
+        uses: lycheeverse/lychee-action@v2
+        with:
+          args: >-
+            --offline
+            --verbose
+            --no-progress
+            README.md
+            CONTRIBUTING.md
+            STYLE_GUIDE.md
+            arista.md
+            azure.md
+            cisco.md
+            docker.md
+            gcloud.md
+            iptables.md
+            kubernetes.md
+            rest-api.md
+            terraform.md
+          fail: true

CONTRIBUTING.md

@@ -0,0 +1,61 @@
+# Contributing
+
+Corrections and focused additions are welcome. The goal is operationally useful, concise, and verifiable reference material.
+
+## Before submitting a change
+
+1. Verify commands against official vendor or project documentation.
+2. State the platform, operating system, or major release when syntax is version-sensitive.
+3. Test examples in a lab or disposable environment when practical.
+4. Mark destructive commands clearly and include a safer inspection step first.
+5. Never commit real credentials, internal addresses, customer data, private architecture, or employer-specific interview material.
+
+## Cheat-sheet structure
+
+Use the following order when it fits the topic:
+
+```markdown
+# Product or Topic Cheat Sheet
+
+> **Applies to:** Product family or major release
+> **Last reviewed:** YYYY-MM-DD
+
+A one-paragraph scope statement.
+
+## Safety
+
+Important operational warnings.
+
+## Quick reference
+
+Commands and concise explanations.
+
+## Troubleshooting workflow
+
+A read-only, least-disruptive-first sequence.
+
+## Official references
+
+- [Documentation title](https://example.com)
+```
+
+## Style rules
+
+- Use one `#` heading per document.
+- Use fenced code blocks with a language identifier when possible.
+- Use placeholders in angle brackets, such as `<interface>` or `<project-id>`.
+- Prefer tables for compact command references.
+- Explain important side effects directly beside the command.
+- Avoid marketing language such as “comprehensive,” “ultimate,” or “one-stop.”
+- Keep conceptual overviews separate from command references when either becomes long.
+
+## Pull requests
+
+A pull request should explain:
+
+- what changed;
+- why the previous content was inaccurate or difficult to use;
+- which official references were used;
+- how the examples were validated.
+
+For a simple typo or broken link, a short explanation is sufficient.

LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2026 Antonio Flores
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

README.md

@@ -1,28 +1,100 @@
-# Cheatsheets Repository
+# Infrastructure and Network Engineering Cheatsheets
 
-Welcome to the Cheatsheets Repository – your one-stop hub for quick-reference guides in the world of networking and technology. This repository is dedicated to providing concise, easy-to-understand cheat sheets for a range of technologies including Cisco, Juniper, Arista, and more.
+Practical quick-reference notes for network engineering, Linux operations, cloud platforms, infrastructure automation, and troubleshooting.
 
----
+> [!WARNING]
+> These notes are a memory aid, not a substitute for vendor documentation, change review, backups, or a tested rollback plan. Commands that alter state can cause outages or data loss. Validate syntax against the exact software and platform release you operate.
 
-**Key Features:**
+## How to use this repository
 
-- **Comprehensive Coverage:** From basic commands to advanced configurations, our cheat sheets span a wide array of topics and technologies.
-- **User-Friendly Format:** Designed for both beginners and seasoned professionals, these cheat sheets are structured to provide information at a glance.
-- **Regular Updates:** The tech world is always evolving, and so are our cheat sheets. Stay up-to-date with the latest commands and functionalities.
-- **Community-Driven:** Contributions are welcome! Help us expand and refine our cheat sheets to cover more technologies and topics.
+- Replace values such as `<interface>`, `<namespace>`, and `<resource-id>` before running commands.
+- Start with read-only inspection commands and capture the current state.
+- Treat `clear`, `delete`, `destroy`, `flush`, `reset`, `prune`, and `--force` operations as destructive.
+- Prefer official documentation for release-specific behavior.
+- Open a content-correction issue when a command is obsolete, unsafe, ambiguous, or vendor-specific.
 
-**Ideal For:**
+## Networking fundamentals
 
-- Network Engineers and IT Professionals seeking quick references.
-- Students and educators in the field of Information Technology and Computer Science.
-- Anyone looking to expand their knowledge in networking technologies.
+| Topic | Reference |
+|---|---|
+| Clos fabrics | [clos.md](clos.md) |
+| Leaf-spine design | [leafspine.md](leafspine.md) |
+| LLDP | [lldp.md](lldp.md) |
+| OSI model | [osi.md](osi.md) |
+| OSPF | [ospf.md](ospf.md) |
+| TCP | [tcp.md](tcp.md) |
+| UDP | [udp.md](udp.md) |
 
-**Get Involved:**
+## Network platforms and routing software
 
-We encourage you to contribute and share your expertise. Whether it's fixing a typo, adding a new cheat sheet, or improving existing content, every bit of help is appreciated!
+| Platform | Reference |
+|---|---|
+| Arista EOS | [arista.md](arista.md) |
+| BIRD | [bird.md](bird.md) |
+| Cisco IOS / IOS XE | [cisco.md](cisco.md) |
+| Fortinet FortiGate | [fortinet.md](fortinet.md) |
+| Juniper Junos | [juniper.md](juniper.md) |
 
-**Navigate with Ease:**
+## Cisco contact center
 
-Our repository is organized for easy navigation, allowing you to quickly find the cheat sheet you need. Whether you're configuring a Cisco router, setting up a Juniper network, or exploring Arista technologies, the right information is just a click away.
+| Product | Reference |
+|---|---|
+| Cisco Unified Intelligence Center | [cisco-cuic.md](cisco-cuic.md) |
+| Cisco Unified Customer Voice Portal | [cisco-cvp.md](cisco-cvp.md) |
+| Cisco Intelligent Contact Management | [cisco-icm.md](cisco-icm.md) |
 
-**Join us in building the most comprehensive and user-friendly tech cheat sheets collection. Star, fork, and contribute today!**
+## Cloud platforms
+
+| Topic | Reference |
+|---|---|
+| AWS services | [awscloud.md](awscloud.md) |
+| AWS CLI | [awscli.md](awscli.md) |
+| Microsoft Azure and Azure CLI | [azure.md](azure.md) |
+| Google Cloud services | [gcpcloud.md](gcpcloud.md) |
+| Google Cloud CLI | [gcloud.md](gcloud.md) |
+
+## Containers, orchestration, and infrastructure as code
+
+| Topic | Reference |
+|---|---|
+| Docker and Docker Compose | [docker.md](docker.md) |
+| Kubernetes and kubectl | [kubernetes.md](kubernetes.md) |
+| Terraform | [terraform.md](terraform.md) |
+| Jenkins CI/CD | [jenkins-cicd.md](jenkins-cicd.md) |
+| Puppet | [puppet.md](puppet.md) |
+
+## Linux and operations
+
+| Topic | Reference |
+|---|---|
+| awk | [awk.md](awk.md) |
+| Debian | [debian.md](debian.md) |
+| HAProxy | [haproxy.md](haproxy.md) |
+| iptables | [iptables.md](iptables.md) |
+| Linux boot process | [linux_kernel_boot.md](linux_kernel_boot.md) |
+| nmap | [nmap.md](nmap.md) |
+| Pacemaker | [pacemaker.md](pacemaker.md) |
+| Corosync | [corosync.md](corosync.md) |
+| Regular expressions | [regex.md](regex.md) |
+| SCP | [scp.md](scp.md) |
+| sed | [sed.md](sed.md) |
+| Xen | [xen.md](xen.md) |
+
+## Development and data
+
+| Topic | Reference |
+|---|---|
+| Git | [github.md](github.md) |
+| Kafka | [kafka.md](kafka.md) |
+| REST APIs | [rest-api.md](rest-api.md) |
+| SQL | [sql.md](sql.md) |
+
+## Maintenance policy
+
+Accuracy-sensitive documents should include an **Applies to** line and a **Last reviewed** date. A review date means the examples received a documentation review; it does not guarantee compatibility with every release or environment.
+
+Repository quality checks validate the maintained documentation surface on pull requests and changes to `main`. See [CONTRIBUTING.md](CONTRIBUTING.md) and [STYLE_GUIDE.md](STYLE_GUIDE.md) before adding or substantially rewriting a sheet.
+
+## License
+
+Content is available under the [MIT License](LICENSE).