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Ciphers, WAL bugs, Posteo, IPv4 / IPv6, LPWAN, Sigfox,, COGS

posted Jun 26, 2016, 10:42 PM by Sami Lehtinen   [ updated Jun 26, 2016, 10:46 PM ]
  • Reminded myself about CBC+ESSIV & CTR & XEX & XTS as well as CMC and EME, as well as speed differences created by CPUs support for AES-NI which makes AES much faster option than other ciphers.
  • Time4VPS servers seem to be awesome. I mean really nice bang for buck for personal use.
  • Had a good weekend, fixed plenty of software bugs in one project. I guess total number of issues fixed was more like 52 or something. Mostly those were pretty simple issues causing uncaught exceptions, which when combined with those certain database transaction scope issues caused major headache. Write ahead logs were growing into gigabytes pretty quickly and that's bad. - Growing WAL logs is also great RAM sucker, because it needs to be checked every time when database is being accessed. When you're getting to the point where WAL is larger than the RAM of the server, you'll start having really bad time at least in performance terms.
  • Read book: Cyber War in Perspective: Russian Aggression against Ukraine - I'll provide quick thoughts and comments later.
  • Wrote internal documentation describing Apache Guacamole Pros and Cons as well as describing it's technology stack, configuration options and possibilities for automated system integration.
  • Carefully studied features, FAQ & privacy documentation.
  • When will the IPv4 get thrown out? And people really prefer IPv6 Only? When all systems aren't configured with IPv4 to begin with, there will be problems. There's nothing wrong with Netware, IPX or serial cables. But it's surprising how many people are clueless about the fact that you need to manually configure both ends to use same settings when using a serial cable. Similarly horrible things like NAT will be most confusing and enraging legacy tech to be found. These nasty things (NAT, private IP ranges, etc) get people confused all the time even today. Simply because most of people don't any more have any idea how it works, they just see that things are broken. There are also SysAdmins out there who don't simply get shell at all, because they've always used GUI. (Ouch!)
  • (no link, it's down) has been down now for quite a while. Sure, that's the problem with sites with single administrator. Things might work great for years. But if brown stuff hits the fan, especially at wrong moment. It might take a while before things are back. Especially if it's extremely sticky brown stuff and it's something which really requires work and not just, oh well, I'll need to reboot it or make a minor disk cleanup or something like that.
  • Checked out Low-Power Wide-Area Network (LPWAN) networking services for wireless telecommunication. In Finland there are two technologies being used LoRaWAN by LoRa Alliance and Sigfox by SIGFOX. Wide-band who needs that these technologies bring you ultra-narrow band (UNB) technology.
  • Studied and it's API in detail. Basic stuff Web hooks and REST API. It's just as everyone else is doing it, with very simple (obviously) interfaces. Only complication there's is the option to use asynchronous mode, but even that is a peace of cake.
  • Google I/O 2016: "Performance is art of avoiding work". - That's sounds great. I'm pretty sure Dilbert is one of top performing employees.
  • Read a long post about Deep Learning and it's inherent problems.
  • Enjoyed explaining obvious things like COGS to a customer.
  • Something different: HAL Tejas