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MariaDB 10.1.28 with WSREP will not start – here’s how you can fix it

If you are running MariaDB 10.1 branch on any major distro (Ububtu, CentOS/RHEL…) with WSREP=ON (indicating replication such as galera), then your MariaDB systemd unit will most likely fail to start.

Steps to reproduce:

  • Install mariadb-10.1.27 or earlier for any distro
  • enable WSREP (have a cluster running)
  • upgrade one node to 10.1.28
  • mysql will simply quit any time you start the systemd unit, with no fishy warning or error messages whatsowver, just a silent insta-death.

If you now try to run mysqld (do a „which mysqld“) in foreground, it will actually keep on running.

Note: use „killall mysqld“ on a different shell to gracefully quit mysqld when running in foreground, because mysqld will ignore you hammering Ctrl+C, duh.

So my guess was: „This has to do with the unit file, or with mysqld_safe“. Turns out i was right, after a bit of googling i found this patch for mysqld_safe, which is just broken in that release.

diff mysqld_safe.bug mysqld_safe.fixed
249c249
< local wr_logfile=$(mktemp wsrep_recovery.XXXXXX)

> local wr_logfile=$(mktemp -t wsrep_recovery.XXXXXX)
271c271
< eval_log_error „$mysqld_cmd –wsrep_recover $wr_options 2> $wr_logfile“

> eval_log_error „$mysqld_cmd –wsrep_recover $wr_options > $wr_logfile“

Source: click here

I wonder how this can happen, do they run their rpm package tests only without replication enabled!?

Of course I hit this in production, where else!? You don’t run replication in testing, because nobody is willing to pay the extra server(s) 😀

FPV Freestyle Session Kreuzberg Bamberg


 

FPV Freestyle Session
Kreuzberg, Bamberg, Germany

Equipment​ ​used:

-​ ​Martian​ ​II​ ​5″​ ​Frame
-​ ​Hglrc​ ​F3​ ​V4​ ​AIO​ ​Flight​ ​Controller
-​ ​Racerstar​ ​BR2206​ ​2200kV​ ​Motors
-​ ​King​ ​Kong​ ​5040​ ​5x4x3​ ​Props
-​ ​Eachine​ ​and​ ​Aomway​ ​5.8G​ ​5dBi​ ​RHCP​ ​Antennas
-​ ​Aomway​ ​Commander​ ​V1 FPV Goggles
-​ ​FrSky​ ​Taranis​ ​Q​ ​X7​ ​running​ ​OpenTX​ ​2.2
-​ ​FrSky​ ​X4R​ & XM+ ​Receiver​
-​ ​GoPro​ ​Session​ ​in​ ​EPIC​ ​MODE!
-​ ​3D​ ​Printed​ ​GoPro​ ​Session​ ​Mount​ ​and​ ​Stock​ ​GoPro​ ​Mount​ ​with​ ​a​ ​Zip​ ​Tie​ ​;)
-​ ​SLS​ ​1300mAh​ ​4S​, mylipo 1300mAh 4S +​ ​Zippy​ ​1600mAh​ 4S ​LiPo-Batteries
-​ ​SkyRC​ ​Q200​ ​AC/DC​ ​Quattro​ ​Battery​ ​Charger

Music:
xJK. – haHAA (https://soundcloud.com/xjkbeats/hahaaaaaaaaa)

Shopping furniture

The other day wanted to go shopping for furniture. But what’s that, they are closed on Sundays!? Well, then let’s at least rip their parking lot a bit.

Intel NUC: Lautes brummen aus dem Lautsprecher, wenn keine Anwendung Ton abspielt

Ich habe heute einen Intel NUC mit CentOS7 neu installiert und beobachtet, dass etwa 5 Sekunden nachdem die Audiowiedergabe stoppt – beispielsweise VLC – die Lautsprecher extrem laut zu brummen anfangen, so als würde man das Klinkenkabel nur halb einstecken.

Meine Vermutung, CentOS schaltet die Soundkarte ab, war dann auch tatsächlich richtig, der Workaround ist hier:

echo 0 | sudo tee /sys/module/snd_hda_intel/parameters/power_save_controller
echo 0 | sudo tee /sys/module/snd_hda_intel/parameters/power_save

Um das permanent zu bekommen, packt man das in die Datei /etc/rc.local und vergisst natürlich nicht, die auch gleich noch mit chmod +x Ausführbar zu machen.

Die Methode, dem Intel-Soundkartentreiber in /etc/modprobe.d Parameter mitzugeben funktioniert bei mir übrigens nicht, der Treiber ignoriert diese.

Ripping around: GIANT CHAIR EDITION!

This video is more than overdue, i procrastinated editing and uploading it way too long.

This was filmed almost 3 weeks ago, we had a lot of fun and a lot of damage while flying around our local XXL Neubert (you get overpriced furniture there, don’t even ask).

First few batteries were just me ripping around the parking lot, then Daniel killed his Eachine Lizard 95 and the girls were getting hungry. Side note: Never go flying with hungry girls, unless you have no more than two batteries with you. End side note.

Anyway, then i decided to finish my last battery at the giant red chair that was standing around (it’s like 30 or so meters high, at the very least), but i did **NOT** scout the location enough and overlooked the number one enemy of every miniquad pilot: WATER! TO THE RESCUE!

Equipment used:

  • Martian II 5″ Frame
  • F3 V4 AIO Board from Banggood
  • Racerstar 2206 Motors
  • King Kong 5040 5x4x3 Props
  • Eachine K-Loverleaf 5.8G 5dBi RHCP Antennas
  • Eachine VR D2 Goggles
  • FlySky i6 Transmitter
  • FlySky ia6 Receiver
  • GoPro Session
  • 3D Printed GoPro Session Mount from Banggood
  • Zippy LiPo Batteries, 1300mAh and 1600mAh
  • SkyRC Q200 AC/DC Quattro Battery Charger

Music: Julian Convex – Sumidagawa https://soundcloud.com/julianconvex

Buildings and Gravity


Today i decided to play with gravity a bit in random spots around Bamberg. Enjoy!Today i decided to play with gravity a bit in random spots around Bamberg. Enjoy!

Equipment used:
– Martian II 5″ Frame

– F3 V4 AIO Board from Banggood

– Racerstar 2206 Motors

– King Kong 5040 5x4x3 Props

– Eachine K-Loverleaf 5.8G 5dBi RHCP Antennas

– Eachine VR D2 Goggles

– FlySky i6 Transmitter

– FlySky ia6 Receiver

– GoPro Session

– 3D Printed GoPro Session Mount from Banggood

– Zippy LiPo Batteries, 1300mAh and 1600mAh

– SkyRC Q200 AC/DC Quattro Battery Charger

Music:
– Ivy Lab – Voltage

– Aphex Twin – Pacman (Power Pill Remix)

FPV Miniquad Vert: Practicing Rolls, Flips Powerloops and Split-S

Today i went out to practice some trick combinations with my 220mm Martian II Mini-Quadcopter.

I know, you pros out there maybe think i’m still shaking a lot and not always staying in the flow, but isn’t that why you practice!? 😉

I’m into flight models since 2016 and into FPV miniquads since Feb 2017, so bare with me! Still, I think i made quite an improvement within the last 4 months 😉

New video: FPV Training Playground

Just me doing some FPV training at the local playground / soccer field.

After I finally got used to flying acro mode, i decided it’s time to raise my rates, lower the d, raise the p and add some speed to the quad.
I think have to practice smoother movement though… 😉

FPV Picnic and building the Wizz racequad

Yet another video is out, as you can probably see our flying skills constantly improve. In the meantime i’ve also been building a new quad, this time without tilting arms, a „regular“ racequad on the Wizzard 220 frame.

Here’s the new quad in the building process:

How often can you crash your FPV race quads in one weekend?

We went out to fly,  and this time there really was a lot of crashing involved. That’s just the way it’s supposed to be if you’re learning to fly, I guess. Especially if you’re trying to pass things with as little distance as as possible, flying proximity, and if you max out the physics of your race quad with rolls and all kinds of stupid maneuvers.

Nuff said, video’s out, enjoy!

cn@ilxrpkd.datensicherung.de