Archive for the 'Services' Category

remapping bad spinning disk storage blocks

Monday, December 18th, 2017

Your good, old-fashioned rotating hard disk storage starts to develop bad sectors?

Dec 17 10:49:47 server kernel: end_request: I/O error, dev sdb, sector 300037184

One of the most easiest, quick and dirty ways to remap them on Linux (e.g. easier than fumbling with dd if= of=)?

Double check:

hdparm –read-sector 300037184 /dev/sdb

And if it is the block and still fails:

hdparm –write-sector 300037184 /dev/sdb –yes-i-know-…

Obviously this zeros the sector and all 512 or 4096 bytes that lived at that place are gone forever, and give way for fresh zeros from a spare, remapped reserve block.

Use only when you know what you are doing, your milage may vary.

Update: If you init a fresh Linux MD RAID, you may want to increase the min speed limit to get things going into production a bit faster:

echo 100000 > /proc/sys/dev/raid/speed_limit_min

Update2: If you are running in some error correcting RAID mode (e.g. not striped RAID 0 ;-) the Linux code will apparently re-write sectors and thus already automatically trigger a remap of those sectors:

end_request: I/O error, dev sdb, sector 301373665
ata2: EH complete
raid1:md0: read error corrected (8 sectors at 301373600 on sdb1)
raid1: sdb1: redirecting sector 301373600 to another mirror

Recompress Update 17.11

Monday, November 27th, 2017

After releasing our initial PDF Re/compress we received praise by first customers and users - and one popular questions: Can you actually reduce the quality much, much more?!

Our initial Re/compress will go thru all the PDF’s objects, and re-writes them in a much more compact and compressed way and also potentially recover and fix some broken files. It would also allow to reduce compression quality and down-sample the image’s resolution.

However, some interested inquires intentionally wanted way worse, smaller, and thus faster to load files. One of the most popular reason? AutoCAD CAD drawing! Those users usually use some print to PDF driver that usually results in tens (if not hundreds) of thousands of vector segments, but also potentially many small, few pixel sized (inline, sigh) image dots from 3d renderings and such. Those would usually not compress very much in our original version. This files also actually cause popular PDF viewers, like Apple’s Preview and naturally even more so Adobe’s Acrobat to hang while it was drawing all this many page content for seconds - panning and zooming was also not a very snappy affair.

Meet Re/compres 17.11 - our first major update: A newly developed “Rasterize pages to bitmap graphics” pass will convert this huge amounts of objects to just a single, highly compressed image. Using the down-sample resolution option you can create a new compressed file, intentionally with “photocopier” like reduced quality. Particularly useful when you want to mail documents to public tenders and potential clients without them having to expose all the fine, zoomable details of the original vector file!

We hope Re/compress and all its features can help you in your daily office workflow, and if you have any other wish or inquiry just let us know, too!

Re/compress PDF.

macOS High Sierra

Monday, September 25th, 2017

The silly name aside (sigh), it is really ridiculous that in 2017 Apple does still not allow us to update the last Beta build to the GM (Golden Master) via a delta update, and instead forces us to download and re-install the whole OS from scratch, again.

Not only for developers this really is a total waste of time (and bandwidth). There are already hundred small design details all over macOS and iOS that are not 100%ly right in the Apple eco-system anymore, this additional annoyances really add up to a way too long list in the meantime!

Testing the Beta on my 15″ Retina MacBook Pro (Late 2013) the graphic performance (e.g. editing videos, but also just browsing the web) was quite sluggish, stability awful, and there was even screen flicker and corruption during booting (hello? - where has atomic mode setting gone? ;-)

The machine run also significantly hotter and battery life was obviously much worse. If Apple did not hot-fix this in the last weeks before the GM release this might very well be the worst macOS release I witnessed to date :-/ #peakbugs

Update: after fresh installation (sigh), even the boot graphic glitches prevail:

A post shared by RenéRebe™ (@renerebe) on

Update: even the Arstechnica mentions “bugs” 9 times, and “issues” 10 times, too. Nobody would have let Microsoft get away with this, and we would have called it the worst Windows Vista release ever, … Just saying, …

Update2: iMovie still has the same problem as the latest beta installation before the GM. On my above mentioned 15″ rMBP with 4k display connected and internal display closed iMovie even crashes straight away on start-up:

Exception Type: EXC_CRASH (SIGABRT)
Exception Codes: 0×0000000000000000, 0×0000000000000000

Application Specific Information:
-[QCCGLRootContext minimalSharedContextForCurrentThread]: Inconsistent state
abort() called

Surprisingly iMovie starts when I open the internal display in addition to the external 4k display. What?

Sick & sad. Really sad.

Update 5/11/’17 this is still not fixed in the macOS 10.3.1 and iMovie 10.1.8 and not 4k related, also happens with an vintage 20″ Apple Cinema Display, :-/ ..! #peakbugs

Update 6/12/’17 this is still not fixed in the macOS 10.3.2

The different kinds of Wake-on-Lan

Sunday, September 24th, 2017

Some time ago I posted about wake on lan being hidden by a cryptic energy BIOS option. This week I was setting up a new test system and wondered what exactly the Linux ethtool:
Supports Wake-on: pumbg
letters actually meant. The man-page is help and it actually is quite simple and logical:

p Wake on PHY activity
u Wake on unicast messages
m Wake on multicast messages
b Wake on broadcast messages
a Wake on ARP
g Wake on MagicPackettm
s Enable SecureOntm password for MagicPackettm
d Disable (wake on nothing). This option clears all previous options.

command line iTunes Connect upload?

Friday, August 25th, 2017


/ITunesSoftwareService.framework/Versions/A/Support/altool –upload-app -f my.pkg -u -p thepassword

Why does Apple tell nobody, let us fight with the UI and bug nightmare that is the Application Loader or Xcode!!! :-/ ???

PS: if you are using an older macOS version you may also need to download the new Apple Worldwide Developer Relations Intermediate Certificate:

And if you install older Xcode versions on a newer macOS they can also overwrite the codesign tool or it’s support files you may get:

The product archive package’s signature is invalid. Ensure that it is signed with your “3rd Party Mac Developer Installer” certificate.

In which case for me it helped re-installing the /Applications/InstallOSX…app/Contents/SharedSupport/InstallESD.dmg’s Packages/BSD.pkg

Your milage may vary! :-/



/usr/bin/xcrun -sdk iphoneos PackageApplication -v “${RELEASE_BUILDDIR}/${APPLICATION_NAME}.app” -o “${BUILD_HISTORY_DIR}/${APPLICATION_NAME}.ipa” –sign “${DEVELOPER_NAME}” –embed “${PROVISONING_PROFILE}”

best Linux screen capture settings of the day

Friday, June 23rd, 2017

ffmpeg -thread_queue_size 128 -f alsa -i default -f x11grab -isync -r 30 -ac 2 -s 1920×1080 -i :0.0+0,0 -vcodec libx264 -preset veryfast -pix_fmt yuv420p -acodec libmp3lame -ar 44100 -ab 192k -threads 4 -y Desktop.mp4

Update: w/ VAAPI e.g. for Intel’s QuickSync:

ffmpeg -hwaccel vaapi -vaapi_device /dev/dri/renderD128 -thread_queue_size 64 -f alsa -i default -thread_queue_size 64 -f x11grab -isync -r 30 -ac 1 -s 1920×1080 -i :0.0+0,0 -vf ‘format=nv12,hwupload’ -threads 8 -aspect 16:9 -b:v 12500k -vcodec h264_vaapi -af “lowpass=f=7000″ -acodec aac -ab 192k -threads 8 ~/Desktop/`date ‘+%Y%m%d-%H%M%S’.mp4`

The miserable High Sierra install experience

Wednesday, June 7th, 2017

Apple just released the first macOS 10.13 “High Sierra” Beta. Actually I’m quite surprised of the lack of inspiration in naming. They switched from nice cat names, to boring California landmark names, only to go form Sierra to High Sierra? Is there nothing else more investing to name it? Also this results in rather poor google experience when you google for high sierra issues and one get’s overloaded with old Sierra stuff, … Maybe they are just too high in their Cupertino UFO spaceship these days, …

Anyways, the install experience, oh my, god, where should I even start. Why the heck can they not publish proper, good old installer disk images? And with this High Sierra Beta they reached a new sad point of annoyance. So first some “macOSDeveloperBetaAccessUtility.dmg” packages has to be downloaded (150k or so), after some system fiddling (btw, what exactly?) You get a “Install macOS 10.13” int the AppStore like with previous macOS versions. But instead of including all the installer image, it is only 5MB in size.

Starting that app does some Apple authorisation (again), think preventing Hackintosh’s, and then starts downloading the installer disk images into /macOS\ Install\ Data/, like InstallESDDmg.pkg.partial, and such.

So the problem will all this error prone steps is that the first time the download got stuck at some 4.8 GB. Restarting this stupid loader app wiped all the data and stated from scratch!!! :-/ So some hour and another 5GB wasted in the internet later, it rebooted the system just to tell me I would not have enough space. Wait what? It could not determine that before all the wasted time and data? And only offer to reboot, ..!

Guess what? At that point the f*cking installer thing again removed all the 5GB+ installer image from /macOS\ Install\ Data/ !!!!1!!!

So instead of me being able to plug in other external disk or whatever for installation. I now again need to wait an hour or two, and load the 5GB+ of data, again, and again.

Why do they have to re-implement this crappy, error prone downloader, when the App Store already has a download facility that may be more stable, continue stopped downloads and would also leave the installer image where it was for the next test install.

Each year the whole install procedure feel more like a hidden, user unfriendly labyrinth maze that you would expect from Microsoft in Windows, but not from a cleanly structured Unix kind of system we expect macOS to be.

Unfortunately it looks like Apple is giving up on this clean structure for the sake of making Hackintoshs harder thru obscurity.

Sad. Just so sad :-/

What’s up at Apple? Make UI great again!

Tuesday, May 9th, 2017

While traveling abroad the other day I needed to save bandwidth and download an SD video of an HD TV series season pass in iTunes. A long search of hidden easter eggs - but I finally found it:

Why do the companies need to change their UI so often, make things more difficult and hide in the least expected corners? Why can this not be simple, context options where one would expect it?

tcpdump IPv6

Friday, March 31st, 2017

tcpdump -i eth0 -v ip6

Latest Mac’s build in hardware test

Wednesday, March 1st, 2017

Historically there was an Apple hardware test that you could boot to check if your Mac’s hardware is all good.

It came to a surprise though, that with newer Macs simply holding the ‘d’ during power on it runs some simple hardware diagnostic, too.

One should probably more often read Apple’s support pages, ..