Change tab size in xfce 4

8 07 2017

If you use Debian 9 in a small screen with xfce 4, maybe you suffer the big tab size of some desktop elements.

For fix that, create a file under ~/.config/gtk-3.0/gtk.css with the following content:

/* reduce padding of tabs */
notebook tab {
min-height: 0;
padding-top: 1px;
padding-bottom: 2px;
/* reduce padding of buttons */
notebook tab button {
min-height: 0;
min-width: 0;
padding: 1px;
margin-top: 1px;
margin-bottom: 2px;

Netns different outgoing source ip address

7 07 2017

Using three network interfaces, assign each one a different address as source ip address for outgoing traffic:

ip netns add blue
ip link set eth1 netns blue
ip netns add green
ip link set eth2 netns green
ip netns exec blue dhclient eth1
ip netns exec green dhclient eth2
echo "IP eth0: "
echo "IP eth1: "
ip netns exec blue curl
echo "IP eth2: "
ip netns exec green curl

Debian Stretch 9 issue with vim: copy and paste

20 06 2017

In Debian Stetch 9 there is a new behaviour in vim, the copy and paste with the mouse is unusual and don’t work as the previous versions did.

For fix that, in the file /usr/share/vim/vim80/defaults.vim comment the lines:

" if has('mouse')
" set mouse=a
" endif

Delete information from one host in Prometheus

30 05 2017

If we have information in Prometheus from one node and we need to remove it, the following api request solve it:

curl -X DELETE -g 'http://IP_prometheus:9090/api/v1/series?match[]={instance="IP_node_to_remove:9100"}'

Force syn date and time

21 05 2017

apt-get install tlsdate
tlsdate -H

Enable autologin in Debian with Systemd

19 05 2017

For allow autologin in a Debian system with systemd (very usefull with testing virtual machines):

Create dir:
mkdir /etc/systemd/system/getty@tty1.service.d/

Create file /etc/systemd/system/getty@tty1.service.d/override.conf with the following content:
ExecStart=-/sbin/agetty --autologin root --noclear %I $TERM

More info:

Disable time sync between host and guest in Linux VirtualBox

19 05 2017

To the following files:

/home/[your_user]/VirtualBox\ VMs/[VM_Name]/[VM_Name].vbox

Add the line:

<ExtraDataItem name="VBoxInternal/Devices/VMMDev/0/Config/GetHostTimeDisabled" value="1"/>

More info: