====== How do I learn to be a 1337 sysadmin? ======

This could take you several weeks.

Don't fuck with your body, so think about doing the following for physical and mental health:

  * Take breaks every hour
    * walk around
    * stretch
    * exercise
  * drink at least 2L of water every day
  * cook yourself a meal every day
    * don't eat microwaved food, it's bad for you
    * mac and cheese every day will kill you

===== basics =====
  - Install [[.ansible:start|Ansible]] on your admin machine.
  - Rent a public second-level domain (example.xyz) for less than 1€/month
  - set up a subdomain of your second-level domain you rent 
    * you might want to use home.example.xyz or lab.example.xyz
    * set the A record to 127.0.0.1
    * set the AAAA record to ::1
  - Set up a [[.:linux:kvm|KVM]] hypervisor **on a separate machine** in your LAN (e.g. a homeserver)

===== make machines =====
  - Create the following VMs:
    - [[.network:dhcp|DHCP]]+[[dns|DNS]] (256MB RAM, 4GB HDD)
    - Fileserver (512MB RAM, 40GB HDD)
    - Directory Server (512MB RAM, 6GB HDD)
  - Install one with a DEB based distribution (e.g. Debian), one with an RPM-based distribution (e.g. CentOS) and a third one with a different OS of your choosing (e.g. Arch Linux, Alpine Linux or FreeBSD)
  - set up static IPv4 and IPv6 for these servers
  - install and configure DNS and DHCP to provide dynamic IPs and resolve hostnames in your network
    - disable the DHCP server on your (home) router!
  - install and configure the following services on your file server VM:
    - TFTP (for PXE boot)
    - FTP
    - SFTP
    - SMBv2 (disable SMBv1!)
    - NFS
  - configure the DNS server to resolve anything below your subdomain
  - create a fourth-level subdomain for the file server
    * e.g. files.home.example.xyz
  - create an Ansible playbook for everything you've done so far

===== down and up again =====
  - delete all VMs and re-provision them with Ansible
  - create an Ansible playbook to provision a LDAP server to a new VM
  - configure all services to use LDAP authentication
    * don't forget [[.:linux:cli:ssh|SSH]]!

===== Containers =====
  - create a new VM for [[.:linux:docker:|Docker]]
  - write a ''Dockerfile'' to create a PostgreSQL instance
  - write a ''docker-compose.yml'' to run the following monitoring software:
    - [[.:linux:sensu|sensu]]
    - [[.:influxdb|InfluxDB]]
    - Grafana
  - set up a [[.:network:reverse-proxy|reverse proxy]] to make it all available on another fourth level FQDN locally
    * you can use Traefik or [[.:nginx|nginx]], for example
  - set up monitoring for all of your services and servers
    - install an agent
    - use SNMP for network infrastructure
    - make a pretty dashboard in Grafana
  - set up Mediawiki on another fourth level domain and document everything you've done
    * use PostgreSQL as backend
  - create a backup VM
    - set up backupninja + borg backups to back up all other hosts
  - monitor the backups

===== The Internet =====
  - set up a server in the [[.:network:internet|Internet]]
  - install and configure a [[.:network:firewall|Firewall]]
    * nftables on Debian
    * firewalld on CentOS
  - move your Mediawiki installation onto the new server
  - reverse proxy that thing
  - back that thing up, you already have a VM for it

===== done. =====
Congratulations. You're an admin. Please provide self-hosted services for the public and try not to get hacked.

===== resources =====
  * [[https://www.reddit.com/r/linuxadmin/comments/2s924h/how_did_you_get_your_start/cnnw1ma/|IConrad on reddit about "what I tell people to do"]]
  * [[https://www.digitalocean.com/community/tutorials|Digitalocean community tutorials]]

==== in this wiki ====
  * [[.:network:|Networking]]
  * [[.:linux:|Linux]]