Unity Ubuntu Topbar disappeared

I have often seen that the Unity Topbar of Ubuntu LTS is hidden or not clean loaded after Login.
It’s Caching Problem of Unity (Compiz) and Lightdm, if the PC is not clean rebooted or started.

Howto fix:

sudo rm -fr ~/.cache/compizconfig-1 \ 
&& sudo rm -fr ~/.compiz && sudo service lightdm restart

Now relogin and check.. if ok do a Profile Backup! with:

tar -cvzf  /usb-backup-stick/compiz.tgz \
/home/username/.cache/compizconfig-1 /home/username/.compiz

Surf Browser Slim Twitter Timeline on Desktop

If you search for a slim twitter client on desktops try the small „surf“ browser

install with:

sudo apt-get install surf

and use
surf https://mobile.twitter.com/yourprofilename

Now you have a slim and clean Twitter Timeline like on Tablets, it can be resized to Banner or Fullscreen.

Locale Umloud Problems Cron

If you run scripts to handle text output by cronjobs your perhaps get problems with umlouds „ÖÄÜ“ cause they are displayed by „**“.
This is a problem cause cron uses „C“ setting as locale, you can test it by setting it into root crontab:

open crontab from root with:

$su - root
$crontab -

insert
* * * * * locale

This will mail cron’s locale echo to the mailbox of root! Read root’s mail!
After tests remove the locale entry at crontab!

Howto fix for Scripts:

open crontab from root with:

$su - root
$crontab -e

insert (for German):

LANG=de_DE.UTF-8 
LC_ALL=de_DE.UTF-8

for US:
LANG=en_US.UTF-8 
LC_ALL=en_US.UTF-8

Postfix: Automatic UFW Firewall Updates

If you use a Mail Server with Postfix you got daily Spam Attacks by Scripts:

How to fix?

  • Install ufw Firewall
  • Run a Scanner Script as  cronjob

On Debian/Ubuntu:

Install ufw:


sudo apt-get update && sudo apt-get install ufw && sudo ufw enable && sudo  ufw logging off

Scan Script:
sudo nano /home/user/firewall-update.sh:


#!/bin/bash
# scan rejected
cat /var/log/mail.log | grep rejected | cut -d"[" -f3 | cut -d"]" -f1|grep -v '^$' > /tmp/firewall.txt
# insert to Firewall
while read line; do sudo ufw insert 1 deny from $line to any; done < /tmp/firewall.txt
# scan "denied"
cat /var/log/mail.log | grep denied | cut -d"[" -f3 | cut -d"]" -f1|grep -v '^$' > /tmp/firewall2.txt
# insert to Firewall
while read line; do sudo ufw insert 1 deny from $line to any; done < /tmp/firewall2.txt
service ufw restart
exit 0

Remark:

  • add to root’s crontab run hourly
  • add lines cat..+ while.. replace rejected by other failed commands login etc..!

Test:


sudo ufw status numbered

Should echo list of banned IP’s! Screenshot of one DAY!

Status: active

To Action From
— —— —-
Anywhere DENY 87.98.131.120
Anywhere DENY 187.178.174.1
Anywhere DENY 46.148.88.115
Anywhere DENY 31.28.86.59
Anywhere DENY 200.6.213.125
Anywhere DENY 200.35.185.180
Anywhere DENY 37.49.227.221
Anywhere DENY 203.60.1.21
Anywhere DENY 78.110.2.2
Anywhere DENY 192.140.8.21
Anywhere DENY 66.240.219.146
Anywhere DENY 171.49.178.169
Anywhere DENY 186.179.219.145
Anywhere DENY 119.235.53.122
Anywhere DENY 95.177.213.224
Anywhere DENY 14.161.43.66
Anywhere DENY 203.143.23.69
Anywhere DENY 104.215.8.206
Anywhere DENY 191.96.249.84
Anywhere DENY 190.190.167.206
Anywhere DENY 95.97.176.158
Anywhere DENY 200.77.219.250
Anywhere DENY 191.248.224.38
Anywhere DENY 91.237.124.222
Anywhere DENY 31.27.32.18
Anywhere DENY 122.174.172.246
Anywhere DENY 208.92.136.194
Anywhere DENY 39.52.234.157
Anywhere DENY 202.188.23.209
Anywhere DENY 154.72.169.179
Anywhere DENY 88.247.177.95
Anywhere DENY 98.116.114.130
Anywhere DENY 203.45.1.236
Anywhere DENY 115.74.190.217
Anywhere DENY 183.129.160.229
Anywhere DENY 203.143.23.66
Anywhere DENY 201.187.101.222
Anywhere DENY 46.13.150.215
Anywhere DENY 104.215.11.242
Anywhere DENY 77.119.247.86
Anywhere DENY 94.46.187.190
Anywhere DENY 78.89.186.118
Anywhere DENY 185.218.184.95
Anywhere DENY 103.10.44.223
Anywhere DENY 167.114.226.176
Anywhere DENY 185.38.154.18
Anywhere DENY 85.105.58.91
Anywhere DENY 149.135.117.174
Anywhere DENY 104.236.166.245
Anywhere DENY 27.115.124.2
Anywhere DENY 181.60.254.53
Anywhere DENY 196.22.248.246
Anywhere DENY 165.49.18.249
Anywhere DENY 159.147.100.63
Anywhere DENY 192.95.17.132
Anywhere DENY 137.74.89.35
Anywhere DENY 193.70.87.209
Anywhere DENY 216.36.187.97
Anywhere DENY 101.187.124.125
Anywhere DENY 2.42.219.63
Anywhere DENY 185.109.169.71
Anywhere DENY 201.26.128.167
Anywhere DENY 133.130.74.177
Anywhere DENY 2.139.229.39
Anywhere DENY 177.1.7.49
Anywhere DENY 103.227.88.130
Anywhere DENY 46.102.196.66
Anywhere DENY 109.230.219.194
Anywhere DENY 180.94.114.47
Anywhere DENY 212.170.109.162
Anywhere DENY 190.24.136.122
Anywhere DENY 82.152.228.49
Anywhere DENY 181.49.39.70
Anywhere DENY 103.240.181.210
Anywhere DENY 189.51.83.246
Anywhere DENY 61.19.16.144
Anywhere DENY 45.76.95.222
Anywhere DENY 178.90.55.176
Anywhere DENY 87.139.234.44
Anywhere DENY 200.116.164.5
Anywhere DENY 24.222.140.202
Anywhere DENY 103.100.209.234
Anywhere DENY 82.201.54.152
Anywhere DENY 84.241.1.21
Anywhere DENY 110.145.123.120
Anywhere DENY 185.32.183.141
Anywhere DENY 200.49.145.161
Anywhere DENY 213.156.120.22
Anywhere DENY 95.59.137.196
Anywhere DENY 185.229.227.5
Anywhere DENY 188.225.171.58
Anywhere DENY 211.24.107.177
Anywhere DENY 186.233.80.51
Anywhere DENY 187.178.242.154
Anywhere DENY 190.223.59.18
Anywhere DENY 202.181.207.212
Anywhere DENY 41.87.95.33
Anywhere DENY 52.175.252.79
Anywhere DENY 103.252.220.20
Anywhere DENY 212.230.98.37
Anywhere DENY 41.180.72.44
Anywhere DENY 196.191.131.50
Anywhere DENY 120.150.227.127
Anywhere DENY 181.211.10.202
Anywhere DENY 218.255.233.114
Anywhere DENY 181.143.94.74
Anywhere DENY 196.38.89.85
Anywhere DENY 190.187.134.246
Anywhere DENY 76.65.196.40
Anywhere DENY 222.102.154.172
Anywhere DENY 221.121.148.77
Anywhere DENY 203.191.174.55
Anywhere DENY 190.25.46.42
Anywhere DENY 169.55.213.44
Anywhere DENY 86.16.10.224
Anywhere DENY 89.96.222.27
Anywhere DENY 202.131.203.163
Anywhere DENY 200.85.52.74
Anywhere DENY 94.23.73.132
Anywhere DENY 41.193.16.218
Anywhere DENY 175.136.232.97
Anywhere DENY 118.219.45.141
Anywhere DENY 205.151.252.203
Anywhere DENY 82.113.59.26
Anywhere DENY 178.33.107.200
Anywhere DENY 82.185.149.169
Anywhere DENY 220.130.186.101
Anywhere DENY 201.33.193.166
Anywhere DENY 178.159.36.60
Anywhere DENY 74.125.82.65
Anywhere DENY 74.125.82.67
Anywhere DENY 209.85.128.193
Anywhere DENY 209.85.128.195
Anywhere DENY 178.32.217.0/24
Anywhere DENY 74.125.82.66
Anywhere DENY 209.85.128.194
Anywhere DENY 209.85.128.196
Anywhere DENY 74.125.82.68
Anywhere DENY 104.236.142.81
Anywhere DENY 60.191.38.77
Anywhere DENY 5.101.0.34
Anywhere DENY 209.126.136.5
Anywhere DENY 145.249.104.109
Anywhere DENY 37.49.226.113
Anywhere DENY 189.112.109.185
Anywhere DENY 172.104.155.22
Anywhere DENY 23.227.207.153
Anywhere DENY 142.4.196.32
Anywhere DENY 210.72.142.7
Anywhere DENY 46.21.174.130
Anywhere DENY 13.91.5.211
Anywhere DENY 212.53.206.58
Anywhere DENY 167.114.60.66
Anywhere DENY 144.217.126.187
Anywhere DENY 144.217.210.228
Anywhere DENY 104.236.163.154
Anywhere DENY 61.236.111.38

Linux: Systemd ignore console-setup settings

If you work on older Laptops and you use a Console only System Setup like on Debian there is a Bug on systemd and the console-setup package since years. After reboot all Font Settings seems gone. But the Settings are not real gone, cause systemd does not pull the settings on boot!

How to fix?

  • edit the crontab of root by

sudo su -
crontab -e

  • insert the /bin/setupcon command on „@reboot“ means on every boot!

@reboot     /bin/setupcon > /dev/null 2>&1 

  • save and exit, reboot now
  • now the PC should echo big Fonts for old eyes „Terminus 20×12 Frambuffermode“

 

Nvidia: Legacy Driver Debian 9.0 Stretch Kernel 4.9 Bug Interface

Current is a UNFIXED Bug on Debian 9.0 Stretch which makes impossible to easy install DKMS Nvidia-Legacy Drivers 304/340 for older Geforce Cards

https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=852152

To run nouveau on upgrade 8.0 to 9.0 go to /etc/modprobe.d and remove MANUAL all blacklist configs (*.conf) of nvidia cause some glued on upgrade and are not purged automatic by the upgrade. Cause they will block nouveau load at boot (xserver-xorg-video-nouveau)

Then run on Terminal:

$sudo update-initramfs -u -k all
$sudo update-grub
$sudo reboot

Remarks:

  • Older Hardware isn’t supported by Legacy Drivers after Nvidia-375!!
  • If you not forced to upgrade to 9.0, then WAIT! up to 3 Month! and checkout Bug Lists.
  • I tried Nvidia Installer Files too (*.run) they don’t work too, seems a API of the Kernel is changed
  • Nouveau Version on Debian Stretch is able to run Kodi (glx)! seen on Geforce 8400GS 256MB
  • On Onboard Geforce Chips like older Laptops HOLD Debian 8.0

Security: Disable USB Drive mount for Users

If you share your Systems and you want to disable USB Drive connects there is a small solution. By default the gvfs Service handle all automounts and drive scans. On old Linux Systems you could purge the complete gvfsd „Backend“ but Ubuntu-Desktop forces some pakets to the default Desktop Package! If you purge it the working Desktop can be destroyed!

It’s easier to disable the „USB Drivers“ called Modules from load on Start! Cause Rules are „Software“ and can FAIL unknown!!

Howto? Edit the /etc/modprobe.d/blacklist.conf and add:

blacklist usb_storage
blacklist uas

Update initramfs (Kernel Image)

update-initramfs -u -k all
reboot

Now try to plugin USB Sticks , they should now be ignored!

To enable USB Drives temporaily do:

$sudo modprobe uas
$nautilus

Now the USB Stick should be able to mount for root!

Advantage? No gvfs, org.freedesktop rules or package deps are touched!

Remark: On Laptops DISABLE all USB Devices for Security Reasons! There should now „Fake Keyboard“ or „Fake Mouse“ be able to enter the Systems!!! (USB Kill Sticks)

Security: Isolated Browser eMail Programs

If you want to be more secure, on Linux you can isolate used programs on different Users! All you need is installed by default!

isolated firefox thunderbird

Howto:

  • Add a new User for eMail and Browser to the System with:

$sudo adduser mailuser
$sudo adduser webuser

  • now install if not installed by default „gksu“ User Switch

$sudo apt-get install gksu

  • copy now the default App Links to webuser’s Home Desktop, for mailuser enter mailuser’s name

$cp /usr/share/applications/firefox-esr.desktop /home/webuser/Desktop/firefox-esr.desktop

  • edit the firefox-esr.desktop by right click on nautilus or a editor and change command line:
  • old:

/usr/lib/firefox-esr/firefox-esr %u

  • to:

gksu -u webuser -w "/usr/lib/firefox-esr/firefox-esr %u"

  • save and exit
  • Now to test click on the Firefox App Link and a Password is asked! Enter the webuser password and you use Firefox on a isolated Account!
  • Do same for thunderbird eMail Client! that no bad Code can access your Emails!
  • Set the Home Folder rights for webuser and mailuser to 700 with:

$sudo chmod 700 /home/webuser
$sudo chmod 700 /home/mailuser

  • Remark: Same Technics available at Windows or other Unix Systems, alternate use VNCSERVER! a App to run Desktops inside Desktops!
  • Advantage: Programs run on isolated RAM Space!