Telekom blocking SMTP Servers without asking Users

Sometimes, you see things you just want to refuse to believe.
While it is true that most problems and quirks of software or hardware are due to really profound reasons and can be fixed quickly, sometimes you just cannot find them easily, if something unexpected happend – something which you never even thought of or you just found to be impossible.
My gamechanger – for the WORST – has been Telekom, which I happily would like to propose for the next BigBrother Award:
To cut a long story short: A friend of mine did order an Webhosting Account at – and this did work without any problem.
I did configure some Domain Redirection, Mail Accounts, included them to the Android Phone of that friend – everything was working just fine.
However, as soon as the person arrived at home, Mail did not work anymore on the phone.
After trying to track down the problem for far too long, I did call the (very nice) support and got some immediate help:
“Are you using a Telekom Line?” – well… Yeah? – “Oh.. Well, they include SMTP Whitelists in the new routers, to stop spammers and we are not on this whitelist… So you can recieve but not send mail…” – WAIT. WHAT?!
A quick check on the WIFI Symbol, IP Range of the Phone and an Network IP DOT 1 in the friendly browser later – “Speedport W724v – What can I do for you?” – Well, [D|F|S][a-z][a-z][a-z]!
Turns out, the new W724V, Entry 2 and Hybrid Home Routers of the Telekom “feature” an SMTP Server WHITELISTE. So if you try to use your nice SMTP Server – nop’! You have to include your own Servers to that list, otherwise connection will be blocked – regardless if you try to communicate via Port 25 or 587 via SSL or encrypted formats. Really, hot, bad, nasty stuff.
One could mention that fighting spamers is a good idea, but this approach is as china-like as it is 1984.
So, kudos Telekom – you just made it impossible for “non-IT people” to use their own not Telekom and al. hosted SMTP service!
More can be found on this german site:

Netflow on Ubuntu

Netflow consists of three parts:
The collector, which collects the connection data on a host,
the capture, which receives data from collectors and writes them to disk in binary format,
the dump tool, which presents the data

We use fprobe as collector and nfcapd as capture tool:

sudo apt-get install fprobe nfdump

fprobe wants to be configured during the installation. It asks for the interface which should be listend upon and where the flow collector does listen. In our example, eth0 should be listend upon and the flow collector is situated on the same computer. Please use for that.

You can edit the frpobe file again:

#fprobe default configuration file


#fprobe can't distinguish IP packet from other (e.g. ARP)

nfcapd needs to be configured by hand.
You need to set nfcapd_start to yes:

# nfcapd is controlled by nfsen

To change the destination folder of the capture files, change the hardcoded DATA_BASE_DIR in /etc/init.d/nfdump

After that, start the services:
sudo service fprobe stop
sudo service nfdump stop
sudo service fprobe start
sudo service nfdump start

After that, you can evaluate the resulting data
cd /var/cache/nfdump

You can also define a filter with ” “, i.e. nfdump -R nfcapd.201510260926 “port 3720” or “ip”

Additional infos:

Removing Windows 10 Diagnostics from Windows 7/8/8.1

Windows 10 “Security?”: We got opt-out-only-all-included-private-Wifi-Password-Sharing with all your Facebook Friends, access to all data, addressbooks, emails, voice and video as well as the possiblity to shutdown hardware you attached to your PC – if MS does not like it. Quite some people from the Facebook and Computerbild Front already upgraded to the new Windows 10 – “don’t get left behind and get your upgrade” – well… it sounds more like a really evil episode of Dr. Who and the Cyberman to me. Ugh.

To get to the point: Microsoft did backport some of his Windows 10 telemetry magic to Windows 7/8/8.1 and installed it unasked as updates. So your data can enjoy its “freedom” even without you upgrading to Windows 10.


TL;DR – Microsoft did backport Windows 10 telemetry to Windows 7/8/8.1. Xvitaly on Github made a nice cmd file, just download it and execute it to remove all the bad updates and Windows 10 Ads. Restart. After that, check the Windows Update Section and disable the Updates in Question. Otherwise, you will install these again on your next Update.

Open-source / private Evernote alternative: Paperwork

I use tools like Google Keep and Evernote from time to time to manage my pile of recipies, data and “knowledge” (what ever that’d be ;)). However, I don’t feel really comfortable and looked for alternatives. There are certain plugins for ownCloud, however, these are basically text-editors at best… Never liked that idea. So I came around Paperwork:
Truth beeing told: It is still in development. It is as bleeding edge as it gets. Sharp as a knife. And yes – I forgot to do backups of my (until then not used) database and lost a lot of data on an simple update… (Yep, the reason why I introduced you to automysqlbackup some days ago…).
But at the moment, it is working very well and I like it very much. I think it will become an really great tool :)!

Private Dropbox/Google Drive/File Sync: Syncthing

I tested quite a lot of sync tools out there: Dropbox, G-Drive, Bittorrent Sync, ownCloud, plain Rsync,… You name it.
But to be true, I never really liked any tool that much: It never really *worked out* somehow: The Mobile Apps were bad, “Servers” did eat up too much performance, etc. etc.
And we don’t want to forget these little itching problems with privacy – thinking about Dropbox, G-Drive and the now closed source Bittorrent Sync…
Well – enter Syncthing:
In truth I can only say one thing: It works. It just, plainly, works for syncing data from your mobile devices to your swarm of servers or pcs.
So give it a shot :)!