Ssh To Linux Host Skill

SSH to Linux Host

Overview

This skill provides a complete workflow for connecting to remote Linux hosts via SSH: managing host configurations (save, list, test), executing commands remotely, and transferring files. It supports SSH key authentication, password authentication, and key-with-passphrase authentication. Connection configurations are persisted locally for reuse.

Quick Start

All scripts are located in the scripts/ directory of this skill. Set them as executable before first use:

chmod +x scripts/ssh_config_manager.sh scripts/ssh_connect.sh scripts/ssh_file_transfer.sh

Workflow

Step 1: Determine Host Configuration

Before connecting, determine if a saved configuration exists or collect connection details from the user.

Check for saved hosts:

bash scripts/ssh_config_manager.sh list

If the target host is already saved, proceed to Step 3. Otherwise, collect the following from the user:

To collect this information from the user, ask a focused question like:

"To connect to your Linux server, I need the following information:

1. Hostname or IP address
2. Username
3. Authentication method (SSH key / password / key with passphrase)
4. SSH port (default: 22)
5. Path to SSH key (if using key auth, default: ~/.ssh/id_rsa)"

Step 2: Save Host Configuration

Save the host configuration for future reuse:

bash scripts/ssh_config_manager.sh save <alias> '{"host":"<ip>","port":22,"username":"<user>","auth_type":"key","key_path":"~/.ssh/id_rsa","description":"My server"}'

The alias is a short memorable name chosen by or suggested to the user (e.g., dev-server, prod-web1).

Supported auth_type values:

• key — SSH private key authentication (recommended, most secure)
• password — Password authentication (prompted at connect time, never stored)
• key_passphrase — SSH key with passphrase (passphrase prompted at connect time)

Step 3: Test Connection

Always test the connection before executing tasks:

bash scripts/ssh_config_manager.sh test <alias>

If the test fails, refer to references/ssh_troubleshooting.md for common issues and solutions. Read that file with:

cat references/ssh_troubleshooting.md

Step 4: Execute Commands

Single command:

bash scripts/ssh_connect.sh <alias> "<command>"

Multiple commands (pipe-delimited):

bash scripts/ssh_connect.sh <alias> --multi "cd /var/log|tail -n 50 syslog|df -h"

Run a local script on remote host:

bash scripts/ssh_connect.sh <alias> --script /path/to/local/script.sh

Direct connection (without saved config):

bash scripts/ssh_connect.sh --direct user@host -p 22 -i ~/.ssh/id_rsa "uname -a"

Step 5: Transfer Files (If Needed)

Upload a file:

bash scripts/ssh_file_transfer.sh upload <alias> /local/path /remote/path

Download a file:

bash scripts/ssh_file_transfer.sh download <alias> /remote/path /local/path

Sync directories (requires rsync):

bash scripts/ssh_file_transfer.sh sync-up <alias> /local/dir /remote/dir
bash scripts/ssh_file_transfer.sh sync-down <alias> /remote/dir /local/dir

Host Management

List all saved hosts:

bash scripts/ssh_config_manager.sh list

View a specific host's config:

bash scripts/ssh_config_manager.sh get <alias>

Delete a saved host:

bash scripts/ssh_config_manager.sh delete <alias>

Configuration storage location: ~/.config/ssh-skill/hosts.json

Common Task Patterns

Check server status

bash scripts/ssh_connect.sh <alias> --multi "uname -a|uptime|free -h|df -h|systemctl list-units --state=failed"

View logs

bash scripts/ssh_connect.sh <alias> "tail -n 100 /var/log/syslog"

Deploy code

bash scripts/ssh_file_transfer.sh sync-up <alias> ./dist /var/www/myapp
bash scripts/ssh_connect.sh <alias> "cd /var/www/myapp && npm install --production && pm2 restart all"

Manage services

bash scripts/ssh_connect.sh <alias> "sudo systemctl restart nginx"
bash scripts/ssh_connect.sh <alias> "sudo systemctl status nginx"

System maintenance

bash scripts/ssh_connect.sh <alias> --multi "sudo apt update|sudo apt list --upgradable"

Troubleshooting

When a connection or command fails, read the troubleshooting reference:

cat references/ssh_troubleshooting.md

Common quick fixes:

• Permission denied: Verify key permissions (chmod 600 ~/.ssh/id_rsa) and that the public key is on the server
• Connection refused: Confirm SSH service is running and port is correct
• Timeout: Check network connectivity and firewall rules
• Host key changed: Run ssh-keygen -R <hostname> and reconnect

Security Notes

• Passwords are never stored in the configuration file — they are prompted at connect time
• SSH key passphrases are never stored — they are prompted or handled by ssh-agent
• Configuration files are stored in ~/.config/ssh-skill/ with user-only access
• Prefer SSH key authentication over password authentication for security and automation
• The scripts use StrictHostKeyChecking=accept-new to auto-accept new host keys while rejecting changed keys