Ubuntu on Nico Maas

Advantech AIR-020X Review

Sun, 05 Mar 2023 12:33:21 +0000

Normally, I am not getting review units. This is due to the fact that I am only hosting this small weblog, along some conference talks - and most companies would probably be better off to send their units along someone with a reach of Linus Tech Tips, or similar.

On the other hand - when I get the possibility to do a review, it can be a bit worrisome for the companies as well, as I am a very honest person. I have been working in tech for some time now and had the honor to build stuff which went to space - and came back to tell the tale. I know what I want in a unit - and what could be a problem.

Ubuntu 20.04 Update bricked KVM Virt

Sun, 27 Dec 2020 11:46:05 +0000

I updated an older Ubuntu 18.04 LTS system to the latest LTS and had (among other things) Docker and KVM installed. KVM is actually quite nice if you “just need” a small VM (pfsense ;)). I actually prefer Proxmox and ESXi, but hey, the right tool for the right job.

After the upgrade to 20.04, kvm did not work anymore and I got a lot of lvm2 errors during apt update / apt upgrade sessions, so a short google later I found this. I was a bit nervous, but the fix did neither hurt my kvm nor my Docker instances

[Dell] T30 Intel AMT Blank Screen on Ubuntu Fix

Fri, 17 Nov 2017 13:25:10 +0000

The Dell T30 is an awesome little Homeserver, packing a punch with the Xeon E3-1225 V5 - and being affordable at about 399 €. It also comes with Intels Active Management Technology / AMT which is an extension of the horrible Intel Mangement Engine (which was all over the place months ago when some genius figured out how to stop that Man-in-the-Middle-always-on chip with some simple commands) - but quite useful - nonetheless. The good thing about this, is that it acts like an DRAC (Dell) / ILOM (Sun) / IPMI (Supermicro) card - so it is an KVM (Keyboard Video Mouse, not the virtualization thingy this time, sorry ;)) extension which allows you to control the server via network as if you were plugged in directly.

Upgrade WSL (Windows Subsystem for Linux) on Windows 10

Wed, 20 Sep 2017 07:30:47 +0000

I had installed WSL (Windows Subsystem for Linux) a long time ago to gain access to Ubuntu 14.04 LTS directly from my Windows 10 Desktop. However, as time passes, Software grows old. Upgrading the Ubuntu Subsystem via apt-get update / do-release-upgrade should work, but that could have some nasty sideeffects, considering that the 14.04 LTS WSL release had been a beta test - so, a reinstall should be better.

Luckily, TechRepublic got this covered. Just open a CMD and run:

[Ubuntu] PERC6/i on Ubuntu 16.04 LTS

Wed, 06 Sep 2017 09:30:11 +0000

To use the PERC6/i i.e. the

03:00.0 RAID bus controller: LSI Logic / Symbios Logic MegaRAID SAS 1078 (rev 04)

on Ubuntu, megacli is the best tool - but rarely available due to the demise of LSI Logic. Good thing that the guys from https://hwraid.le-vert.net put together a nice repo to host the latest RAID files. And yes, for everyone that does not like the idea of including a foreign repo - sorry to disappoint here :/.

Reboot Ubuntu if init daemon fails / systemd died

Thu, 27 Apr 2017 08:15:53 +0000

I got following error on an really badly “injured” Ubuntu machine:

Failed to start reboot.target: Failed to activate service 'org.freedesktop.systemd1': timed out
See system logs and 'systemctl status reboot.target' for details.
Failed to talk to init daemon.

Rebooting was not possible anymore, due to the beauty of 2933 zombie processes - slowing down the machine to a crawl.

Dell Servicetag on Ubuntu

Tue, 06 Dec 2016 10:02:48 +0000

You can find out your Dell/Sun Servicetag on Ubuntu via:
sudo dmidecode -s system-serial-number

[Ubuntu] Use Molly-Guard to stop shooting your own leg

Fri, 23 Sep 2016 08:00:06 +0000

If you’re working on some dozens of linux servers (or even more than 100,.. as in my case), you end up doing administration via SSH - which is the way to go. And chances are, that you’ll get dozens of SSH connections open in dozens of tabs and you did some updates on some of those servers and want to restart this thing with a quick sudo reboot now…
I won’t lie if I say, it happend more than once that I accidentally rebooted the wrong server - at least that was the case more than a year ago.
For the last year, since I have been using Molly-Guard - that did not happen once. Why? Because Molly-Guard does stop the reboot command if it detects that you’re issuing it from an SSH console - and asks for the server name. If you’re entering it correctly - it will reboot. If you’re in a frenzy, doing your “sudo reboot now” and enter name serverB while you’re on serverA - yep, Molly-Guard will stop you from shooting yourself in the leg. Neat, ain’t it?

[Ubuntu] Letsencrypt with Apache and Freeradius

Mon, 16 May 2016 08:00:53 +0000

This little tutorial describes how to use Letsencrypt with Apache, Freeradius and Auto-Renewal of the Certificates.

Install Letsencrypt

sudo apt-get update  
sudo apt-get install git  
cd /opt  
sudo git clone https://github.com/letsencrypt/letsencrypt /opt/letsencrypt  
cd /opt/letsencrypt

# Become root  
sudo su

# "Order" certificates (replace SERVERDOMAIN.COM with the DNS of your Server!)  
./letsencrypt-auto --apache -d SERVERDOMAIN.COM --rsa-key-size 4096  
Enter Contact Mail: mail@SERVERDOMAIN.COM  
Configuration Type: Secure #is best, as it does redirect insecure http to https)

# Read PATH variable  
echo $PATH

# Cronjob for certificate renewal  
#you should under all circumstances replace the string following PATH= with your own, as read with the command above.  
#Seperate with ; from the rest of the command like shown in the example  
crontab -e

# letsencrypt
30 2 * * 1 PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games;/opt/letsencrypt/letsencrypt-auto renew &gt;&gt; /var/log/le-renew.log
35 2 * * 1 /etc/init.d/freeradius restart
35 2 * * 1 /etc/init.d/apache2 restart

Configure Freeradius

cp -r /etc/freeradius/certs/ /etc/freeradius/certs_bkp  
rm /etc/freeradius/certs/*.pem  
cp /etc/freeradius/eap.conf /etc/freeradius/eap.conf_bkp

vi /etc/freeradius/eap.conf

#certdir = ${confdir}/certs
#cadir = ${confdir}/certs
certdir = /etc/letsencrypt/live/SERVERDOMAIN.COM
cadir = /etc/letsencrypt/live/SERVERDOMAIN.COM
#dh_file = ${certdir}/dh
dh_file = ${confdir}/certs/dh
#private_key_password = whatever
private_key_file = ${certdir}/privkey.pem
certificate_file = ${certdir}/cert.pem
CA_file = ${cadir}/fullchain.pem

# Configure access rights on /etc/letsencrypt  
cd /etc/letsencrypt/  
chgrp -R ssl-cert archive csr keys live options-ssl-apache.conf renewal # set group of cert/key dirs to ssl-cert  
find . -type d -exec chmod g+xs {} \; # directories executable and setguid (set group ssl-cert for new files/dirs)  
find . -type f -exec chmod g+r {} \; # files readable

# Restart Freeradius  
service freeradius stop  
service freeradius start

Additional infos: https://www.digitalocean.com/community/tutorials/how-to-secure-apache-with-let-s-encrypt-on-ubuntu-14-04

[Ubuntu] Install Docker

Thu, 14 Jan 2016 19:00:44 +0000

This is a short guide to install the recent Docker Version from the official ppa on Ubuntu 14.04 LTS - along with some other great tools like docker-compose.
Please bear in mind, that Docker needs an 64 Bit System to work with :)! So no i686 plattforms from here on.

# Add Docker Key  
sudo apt-key adv --keyserver hkp://p80.pool.sks-keyservers.net:80 --recv-keys 58118E89F3A912897C070ADBF76221572C52609D  
# Add Repo  
echo "deb https://apt.dockerproject.org/repo ubuntu-trusty main" | sudo tee /etc/apt/sources.list.d/docker.list  
# Update and Install  
sudo apt-get update  
# Install Recommended Package  
sudo apt-get install linux-image-extra-$(uname -r)  
# Install Docker itself  
sudo apt-get install docker-engine  
# Useradd - so you can use docker with your own user without sudo  
sudo usermod -aG docker ${USER}  
# Install pip  
sudo apt-get install python-pip  
# Install docker-compose  
sudo pip install docker-compose  
# Test Docker Install  
sudo docker run hello-world  
# After an additional reboot, you will be able to use docker with your own user (also recommend because of the the new linux-image-extra 🙂

[Ubuntu] Screenshot to File

Thu, 06 Aug 2015 16:00:00 +0000

Just a quick tip. If you want to do a screenshot of a certain area of your screen and save it to a file, use the command CTRL + Shift + Print on Ubuntu Linux.

[Ubuntu] Automatic Backup of MySQL Databases

Mon, 22 Jun 2015 17:35:54 +0000

Just install automysqlbackup via apt-get.
You can configure the whole system via /etc/default/automysqlbackup
Backups will be sent to /var/lib/automysqlbackup

[PiAndMore] Raspberry Pi Appliances

Sat, 20 Jun 2015 13:25:20 +0000

Here is the presentation to my Appliances Talk @ PiAndMore 7 (Trier, 20.07.2015)

RPiAppliances_PiAndMore7.pdf (0,6 MB, PDF)

[Security Spotlight] Upgrade OpenSSL to 1.0.1g - Heartbleed Bug - Urgent!

Mon, 07 Apr 2014 14:00:49 +0000

So, thats no joke: OpenSSL broke badly!
Here is the background: https://heartbleed.com/

And as there is no zero-hour-fix for Ubuntu (including 12.04 LTS…), I decided to take chances and overwrite my existing OpenSSL 1.0.1 with the new code. It worked out flawlessly - but your system could REALLY break. Thats as dirty as it possibly could get!

wget http://www.openssl.org/source/openssl-1.0.1g.tar.gz
tar -xvzf openssl-1.0.1g.tar.gz
cd openssl-1.0.1g/
./config --prefix=/usr
sudo make
sudo make test
sudo make install

[Ubuntu 12.04] Resolve Grub Boot Problems

Wed, 20 Nov 2013 16:19:32 +0000

If you killed your trusty grub (i.e. by new Install of Windows 8.. :/) you can repair it quite easily:

Boot with an Ubuntu 12.04 Live CD
CTRL + ALT + T

sudo add-apt-repository ppa:yannubuntu/boot-repair
sudo apt-get update
sudo apt-get install -y boot-repair && boot-repair

And click on the repair button! Done!

Source: http://askubuntu.com/questions/333483/how-to-restore-grub-after-deleting-it-from-windows-8-disk-manager

Disable Root Account in Ubuntu

Fri, 15 Nov 2013 18:56:26 +0000

An freshly installed Ubuntu got the root Account set to the best and most secure state ever: DISABLED!
But if you use ready-made Appliances and such, most of these Ubuntu Appliances come with an enabled Root Account. How to disable this account? Easy:

sudo usermod -p '!' root

Source: https://serverfault.com/questions/178080/how-do-i-disable-root-login-in-ubuntu

[Ubuntu 12.04] EEE PC 1015 PN with Ubuntu 12.04 LTS

Fri, 06 Sep 2013 14:57:03 +0000

I could not help myself but felt the need to have at least one real “Dual Boot” system (not VMWare Stuff) - so I setup my Asus EEE PC 1015 PN with the Ubuntu 12.04 LTS according to mtrons excellent Tutorial ( https://sites.google.com/site/mtrons/howtos/eeepc-1015pn ) which worked out right out of the box.

But - as I haid some trouble with the old Broadcom Wifi/BT Card in Windows 7, I went for an Intel 6250 AGN/WiMax Card. I do not use WiMax and would love an BT option - but the price point of that card on ebay finally got me to press the “Buy now” button. I thought “Well, it is an Intel Card - that should work quite well and stop throwing me out of the University Wifi with no chance but doing an hard reboot of the Laptop to solve the problem” - yeah - it really did. BUT - somehow, after some time and updates to the Ubuntu System, I lost connectivity: Network Manager was nagging for the password all the time - without a reason. Finally I found the solution on this website: http://askubuntu.com/questions/104651/how-do-i-get-wireless-working-on-an-asus-notebook-u56e - with some changes.

[Linux] Ubuntu Root Server to VMWare BareMetal Recovery

Fri, 18 Mar 2011 07:00:41 +0000

I got an root server on the net hosting an important website and am doing backups on a daily base using Tartarus ( http://wiki.hetzner.de/index.php/Tartarus_Backup-Konfiguration ). But as we all know: Backups are only worth a penny if they really work and are usable after an crash. Therefor I did try to recover the “dead called” machine onto BareMetal - or at least BareAir - as it was an VMWare Machine I used.

SSH Tunneling

Wed, 06 Jan 2010 12:30:44 +0000

One of the most important things by working in “dangerous” Networking Enviroments is protection.

And by that I don’t mean the usual (and important!) Anti Virus, Anti Malware and Firewall Software, but Traffic Tunneling, meaning VPN or SSH.

SSH is the secure equivalent to the good old (and Plaintext transmitted) Telnet. And its also more powerful: Its use is not limited to remote Control, but can also provide an secured Datatunnel through which all your Traffic to your Remote Location (i.e. an Mysql Database, Web- or Mailserver or the Web itself) is tunneld - and encrypted. Giving therefore little to no chance to “Wiresharkes” and other Cable Tappers or Span Users.

Get Ethernetcard working again in Linux under ESXi

Thu, 16 Jul 2009 13:25:10 +0000

After installing Ubuntu Server on Vmware ESXi, I couldn’t find a NIC:

sudo /etc/init.d/networking restart

Reconfiguring network interfaces…

eth0: ERROR while getting interface flags: No such device  
SIOCSIFADDR: No such device  
eth0: ERROR while getting interface flags: No such device  
SIOCSIFNETMASK: No such device  
SIOCSIFBRDADDR: No such device  
eth0: ERROR while getting interface flags: No such device  
eth0: ERROR while getting interface flags: No such device  
Failed to bring up eth0.

Problem is that the ethernet MAC addresses are cached.