CrystalLabs — Davor Ocelic's Blog
Tech blog about Unix, GNU/Linux, software development, systems administration, cloud, open source, privacy, and ethics.
Unix and GNU/Linux
Unix history. CTSS, BTS, Multics, ITS, Unix, C, BSD, Unix wars, Motif, CDE, GNU, Linux. AT&T, Bell Labs, CSRG, UCB, Sun Microsystems, Novell.
Original Unix, BSD, GNU, and Linux books, papers, videos, and similar materials.
Unix philosophy. Software tools. Simple is beautiful. DOTADIW, KISS. Minimal, simple, clear. Modular, reusable, testable, quick. Free, unrestricted, customizable.
Unix, GNU/Linux and Debian GNU documentation. Where is it, how to access it. Man, info, tldr, /usr/share/doc/, TAB, IRC, RFCs, HOWTOs, FAQs, kernel docs. Quiz.
Unix, BSD, GNU, Linux, IT. Mailing lists, TUHS, COFF, IH, RISKS. BOFH, UGU. HCoop, SDF. IRC.
Docker
VMs, containers, Docker. Dockerfile, images, containers. Docker and docker-compose. Description and use.
Git (Version Control System)
Introduction to file versioning. History of version control tools SCCS, RCS, CVS, Subversion, BitKeeper, and Git. Funny story.
Git. Multiple repository origins. Projects mirrored at different hosting platforms.
OpenStreetMap (OSM)
Computer cartography. OpenStreetMap (OSM), Mapnik, Tirex. WMS, TMS, WMTS, KML, Slippy. Leaflet, OpenLayers, QGIS, Marble. iD, JOSM, Go Map!!, OsmAnd. GPS, GPX.
Computer cartography. OpenStreetMap (OSM), Leaflet, Slippy. Custom map viewer.
Computer cartography. OpenStreetMap (OSM), MapProxy. WMS, WMTS, Slippy, TMS, KML. Custom tile proxy and cache.
Unix Infrastructure
Practical introduction to MIT Kerberos 5. KDC, kadmin.local, kadmin, PKINIT, exhaustive troubleshooting recipes.
Practical introduction to OpenLDAP. Slapd, slapd.conf, olc, slapd.d, cn=config, nsswitch.
OpenAFS – global, distributed, network filesystem from CMU. Practical installation. “Where ever you go, there you are”.
Networking
Physical one-way data link. 100Mbps ethernet + UDP/IP. File transfer with ncat or socat and tar.
ZeroMQ async messaging. Can run brokerless. Runs on top of ITC, IPC, PGM, TCP, TIPC, UDP, or VMCI. BSD sockets-like API. REQ-REP, PUB-SUB, and PUSH-PULL pattern.
Three-point VPN Gateway. WireGuard, IPTables/NFTables, DNS, dnsmasq. VPN server and Internet gateway on different machines.
Short Tips and Tutorials
Unix, Linux password reset. Bootloader, grub, init, mount, passwd, reboot, sysrq. Funny story.
Misc
Your own blog like crystallabs.io. Hugo framework, minima-crystallabs theme. Clone and run. Quick success.
Lt1. Linux, GNU, diskless, single floppy, 1.44MB, 2MB flash RAM, ramdisk, rescue disk.