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Hands-on Lab·LPIC-1

SSH posture, limits, and encrypting a file

Objectives 110.2 and 110.3 cover host hardening and encryption. This guide reads what the SSH daemon is ACTUALLY running with - which is not always what the config file says - looks at the resource limits a user cannot exceed, and finishes by encrypting and decrypting a file with GPG symmetric encryption, leaving no key material behind.

102: Security Guide 24 of 33 Intermediate

One Debian-family host. Everything is read-only except the GPG demonstration, which works inside a directory created and removed by the page.
Server NameIP AddressOSRolesCPURAMHDD
LPIC1-A01192.168.0.76Ubuntu 26.04 LTSDebian-family host - dpkg and apt, which objective 102.4 names2 Core4 GB50 GB

This guide includes

Use this for host hardening and encryption. This matters because sshd -T prints the effective configuration - which is not what the file says, and is what actually applies.

Before you start

  1. What the SSH server is actually running with

  2. Limits a user cannot exceed

  3. Encrypting a file, and proving it is unreadable

Official sources