koldfront

clear and reset - but fast #commandline

🕧︎ - 2024-04-28

When working in a terminal emulator the command clear is nice to declutter and still allow scrolling back through old output, and reset is nice to also get rid of the scrollback - eg if you are debugging and don't want to accidentally be confused by old output.

There's one annoying thing though, while clear is almost instant, reset takes a second. Ugh.

From a fediverse post I learned that tput reset does the same thing only without the delay! So I quickly made a symlink from ~/bin/reset pointing to /usr/bin/tput and now reset is instant - at least in Sakura.

The latest release of ncurses was yesterday, and the release announcement has this paragraph:

tput and tset

   + add "-v" option to tput, to show warnings
   + modify reset command to avoid altering clocal if the terminal
     uses a modem
   + modify  reset feature to avoid 1-second sleep if running in a
     pseudo-terminal

I don't quite understand it, as tput is fast for me, but let's see when ncurses 6.5 rolls into the various operating systems.

🕧︎ - 2024-04-28 - 0 comments

Devops Engineer position at Novonesis in Copenhagen #biotech #linux

🕥︎ - 2024-04-23

If you're good a Linux and want to work in a research organisation in an environment where you're expected to look after racks of servers, from making sure the right ones are there with the right components, to keeping the operating system (Ubuntu) updated, the virtual machines spinning (Proxmox), the distributed network storage in top shape (Ceph), and the tape robot fed, here is a job ad for you to check out:

· Devops Engineer, Lyngby, Denmark

You'll be expected to analyze trends (Grafana) and catch problems before they get out of hand, learn from your mistakes and document them via improved monitoring (Nagios), and to respond to the whims of researchers changing focus. A bunch of responsibility and the freedom to find a good solution - and some opinionated colleagues to discuss it with as well.

🕥︎ - 2024-04-23 - 0 comments

Just call me Mr. NNTP #nntp #usenet #lantern #illuminant #activitypub

🕤︎ - 2024-04-15

Today I counted the number of NNTP-servers I have implemented for different purposes over the years.

I wonder if I qualify for Guinness book of records - I have implemented 5 different NNTP-servers:

d-a-d.com discussion forum (Perl)
Feedbase - RSS/Atom reader (Perl)
Lantern - blog engine (Haskell)
olduse.net - nntp time travel (Haskell)
Illuminant - ActivityPub server (Haskell)

Some years before implementing Illuminant I also sketched up an NNTP-based microblogging system, which hasn't been implemented (yet?)

🕤︎ - 2024-04-15 - 1 comment

Under attack?! #net

🕚︎ - 2024-03-31

Yesterday evening my home router started acting up. Instead of ping showing a latency of a couple of ms it went up to hundreds, and on top of that it started dropping 40-80% of the packets.

I tried turning it off and on again, wildly guessing that my ISP maybe had done some kind of upgrade or something.

It started up nicely, but then bogged down again. After a while I looked at the smokeping graph, which confirmed that something was wrong:

Smokeping graph showing the latency to the router on my LAN going haywire

I noticed that on my three DNS servers, one behind this router and two on VPS's, named was in the top of the CPU usage list. Hm.

ngrep'ing traffic on port 53 revealed a single IP doing a lot of requests for asjo.org. As in thousands.

I even got a warning from one of the VPS hosters telling me about the sudden spike in outbound traffic.

I started dropping the packets from that IP on the servers, and in the router, the outbound traffic disappeared, and my router no longer suffered. Yay!

Graph showing the sudden increase in traffic on one VPS

It seems like a weird low-key DoS attack, but it's kind of hard to understand. It's not that disruptive - luckily - and it seems to come from one IP-address only.

Well, almost. After I started dropping all packets from that IP, another one showed up as excessively active, so I started dropping packet from that one as well. Almost as soon as I did, the barrage from this second IP stopped completely.

The first IP, however, is still sending UDP packets at some 1-2 MBps to each VPS, here more than 24 hours later. Go figure.

I know that various people mistake my domain asjo.org for something else from time to time (when I had a Twitter account @asjo that also happened quite a bit), but what this IP-address - apparently somewhere in central China - has against my DNS servers, I can't tell. It's odd.

🕚︎ - 2024-03-31 - 0 comments

Atomic Blonde (2017) #movies

🕥︎ - 2024-03-29

Tried to watch Atomic Blonde tonight, as it is available on Danish National Television - I bailed after 30 odd minutes; it wasn't for me.

🕥︎ - 2024-03-29 - 0 comments

Early Unix rand() #unix

🕥︎ - 2024-03-12

I have mentioned The Unix Heritage Society mailing list before - fun stuff comes by on it from time to time.

Today Douglas McIlroy replied to a thread about the early Unix rand() routine and who had written a funny note in the documentation, recalling an early story of password breaking:

When Ken pioneered password cracking by trying every word in word lists at hand, one of the password files he found plenty of hits in came from Berkeley. He told them and they responded by assigning random passwords to everybody. That was a memorable error. Guessing that the passwords were generated by a simple encoding of the output of rand, Ken promptly broke 100% of the newly "hardened" password file.

Ken Thompson replied:

i wrote the generator.
dmr or rhm wrote the comment.

🕥︎ - 2024-03-12 - 0 comments

.signatures #usenet #email #amiga

🕕︎ - 2024-02-24

A staple of usenet and email is the .signature. I just had a little peek at a usenet archive to find some of my old ones.

1992:

                                      .
                                     -*-
  Adam_Sjoegren@thesystem.bbs.bad.se   \O_  BBS    +45-31-354775
  Copenhagen, Denmark                   |   ANet betatester
  GCChost support DK                   / \  FidoNet    2:230/149

GCChost was software for running a FidoNet node - it was very configurable through ARexx, and at some point I think I started handling licenses for Denmark (the author was in Italy).

ANet was BBS software from Sweden that I was running, it had a cool interface where navigation was done by typing "shortest command prefix", automatically figured out by the software.

My BBS was called "The system", with that capitalization, for some... uh... artistic or otherwise self-indulgent reason.

1993:

 Adam Sjoegren          Interstellar Navigation      DLG BB/OS 24h
 Copenhagen, Denmark      asj@inav.bbs.bad.se        +45 31354775
 EMS/GCCh support DK   * Powered by AGA and 040 *    16.8k USR Dual

GCChost was replaced by EMS, by the same author, which was designed to handle other types of mail/news systems than FidoNet - we all had email and usenet envy in those days - so it was attractive.

By this time I had changed the name of my BBS to Interstellar Navigation, and I had changed software to the Canadian developed DLG, and it was running on my Amiga 4000, which I was very proud of. It was very expensive as well.

I kind of liked the little stick figure in the older .signature, and have taken to putting a variant in motd on my machines these days, eg:

$ ssh virgil
Linux virgil 6.1.0-18-amd64 #1 SMP PREEMPT_DYNAMIC Debian 6.1.76-1 (2024-02-01) x86_64
   _.
   \O_.    virgil: PC, Copenhagen
    |              AMD Ryzen 5 2400 GE (8 cores)
 ._/_\_,           64G memory, 1.9T disk
  o   o

Last login: Sat Feb 24 15:20:02 2024 from 192.168.1.102

Just for fun.

🕕︎ - 2024-02-24 - 1 comment