linux-sysadmin-skills CLAUDE.md

linux-sysadmin-skills CLAUDE.md is an instructions file for coding agents from HermeticOrmus/linux-sysadmin-skills. It costs 432 tokens per session, scanned A, original, MIT.

A set of guided Linux administration checklists for Debian and Ubuntu-based computers. It covers security, performance, diagnosis, and monitoring using common system tools.

In plain words
What is it for?
Use it to review SSH access, firewalls, updates, services, logs, resource usage, running processes, and system health. It is intended for interactive administration of Debian or Ubuntu derivatives.
Why use it?
It helps you investigate and change a Linux system in a consistent order, while explaining risky actions before they run. This reduces the chance of locking yourself out or damaging the system.

Instructions file

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add instructions/hermeticormus/linux-sysadmin-skills/claude-md
Clone the repo
git clone --depth 1 https://github.com/HermeticOrmus/linux-sysadmin-skills

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for linux-sysadmin-skills CLAUDE.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/hermeticormus/linux-sysadmin-skills/claude-md.svg)](https://agentmods.dev/instructions/hermeticormus/linux-sysadmin-skills/claude-md)
Your own site
<a href="https://agentmods.dev/instructions/hermeticormus/linux-sysadmin-skills/claude-md"><img src="https://agentmods.dev/badge/instructions/hermeticormus/linux-sysadmin-skills/claude-md.svg" alt="Measured on agentmods" height="20"></a>
Per session 432 This file is loaded in full into every session.
When invoked 432 The same file — it is already loaded in full.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00432 $0.00432
Opus 5 $0.00216 $0.00216
Sonnet 5 $0.00086 $0.00086
Haiku 4.5 $0.00043 $0.00043

Measured 5d ago against content hash 54c5880b0242, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

linux-sysadmin-skills CLAUDE.md scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 5d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

CLAUDE.md · 32 lines

How it starts

The opening of the file, as written. The whole thing — 32 lines — stays where its author put it; the contents beside it link to each section on GitHub.

CLAUDE.md

A toolkit of five Linux system administration workflows for Debian/Ubuntu-family machines (apt, systemd, journalctl). Each workflow is a checklist-driven, step-by-step procedure Claude runs interactively with you. Merge with project-specific instructions as needed.

These target Debian and Ubuntu derivatives. The package commands assume apt; the service and log commands assume systemd and journalctl.

Safety rule: destructive operations are confirmed before they run. Anything that removes packages, edits firewall or SSH config, changes kernel parameters, kills processes, or clears caches is explained first, including how it could lock you out, and waits for your go-ahead. Read-only inspection runs without prompting.

1. Security

Audit and harden the system. Covers user and access control, SSH hardening, firewall (UFW), updates and patches, services and ports, file permissions, logs and monitoring, application and network security, and backup. Each change is explained with its security benefit and its lock-out risk before it runs.

2. Performance

Analyze and optimize performance. Assesses CPU, memory, disk, network, and process state, identifies the bottleneck, then applies targeted tuning (kernel parameters, service trimming, resource limits) with before-and-after measurement.

3. Diagnose

Diagnose a specific failing service or system issue. A systematic loop: describe the problem, gather evidence from journalctl and systemctl status, find patterns, check recent changes, form and test a hypothesis, apply the fix, verify resolution.

4. Monitor

Check overall system health on demand. A read-only sweep of CPU, memory, disk, network, processes, critical services, temperatures, and recent log errors, ending in a health summary that flags concerns.

5. Maintain

A routine maintenance pass. Updates and upgrades packages, removes unused packages, cleans cache, scans logs for errors, checks disk space, verifies critical services, and confirms backups. Destructive steps ask first.

Read the full file on GitHub · 32 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 5d ago First seen · 32 lines · 432 tokens per session scan A 54c5880b0242

Subscribe to this mod's changes

linux-sysadmin-skills CLAUDE.md is an instructions file published in the GitHub repository HermeticOrmus/linux-sysadmin-skills (2 stars, last pushed 3mo ago), licensed MIT. It adds 432 tokens to every session, about $0.0022 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

Related

Other instructions, from other repositories