Set static ip address in Ubuntu 19.04

The network configuration settings for the server edition of Ubuntu are now stored in the following location. Create the file if it does not exist.

sudo vi /etc/netplan/01-network-manager-all.yaml

Add or edit the config file to the following. Change eno1 to your interface name and the address and gateway to the appropriate IP’s

For more information, see netplan(5).
 network:
   version: 2
   renderer: networkd
   ethernets:
     eno1:
      dhcp4: no
      addresses: [192.168.200.24/24]
      gateway: 192.168.200.1
      nameservers:
        addresses: [8.8.8.8,8.8.4.4]

Now apply the changes with the following command.

sudo netplan apply

OpenVas set password for user

After installing OpenVAS you may need to setup a user. Running the following command will create the user admin and will print the password for the user below.

openvasmd --create-user admin

Example output.

User created with password 'b4539967-c521-fe41-d255-aeb53e735h9a'.

If needed you can delete a user with the following command

openvasmd --delete-user=USERNAME

Verify Ubuntu iso on Windows

On Windows you can use the CertUtil utility to verify an iso image.

First, you’ll need the checksum of the iso. Should be on the page where you downloaded the iso. More info about that here.

Next generate the hash by running the following in a command prompt. Replace the path and ISO name with the one you downloaded

certutil -hashfile Downloads\ubuntu-19.04-live-server-amd64.iso sha256

Example output

SHA256 hash of Downloads\ubuntu-19.04-live-server-amd64.iso:
25d483341ccd0d522a6660b00db933787c86c47b42f1845bcf997127f4b61e9d
CertUtil: -hashfile command completed successfully.

Compare the output with the checksum. If they are the same, you should be good to go.

Raspberry Pi – Ping IP Address and Toggle LED

The following script is for monitoring if an IP address is reachable or not. If it becomes unavailable the script will turn on a LED that is plugged into one of the GPIO pins of the Raspberry Pi. View pinout here

Script

#!/bin/bash
# Script to ping ip address and turn on LED on if device is unreachable.
                                                                                                                                                                                                 nPin="18"  # Change if GPIO pin is different                                                                                                     
ledPin="gpio${nPin}"                                                                                                                                                                                                                            toPing="8.8.8.8"  # Change to address you want to ping

echo "${nPin}" > /sys/class/gpio/export
echo "out" > /sys/class/gpio/${ledPin}/direction

if ( fping -r1 $toPing | grep -v alive ); then
         echo "Internet unreachable"
         # Turn on LED
         echo "1" > /sys/class/gpio/${ledPin}/value
 else
         # Turn off LED 
         echo "0" > /sys/class/gpio/${ledPin}/value
 fi

Save script as ping_led.sh and make it executable.

chmod +x ping_led.sh

and run the script.

sh ping_led.sh

Run script in crontab

You can setup the script to run every minute using a crontab

crontab -e

Add the following line

*/1 * * * * /home/pi/ping_led.sh

Should now execute the script every minute and not need any human interaction.

LibreNMS manually adjust GPS coordinates for a Geo Location

The locations are stored in the LibreNMS locations table

mysql -u librenms -p librenms

To list all the locations

select * from locations;

Set the specific coordinates for a location using the following command.
Replace the lat and lng, also the id should match the line your wanting to update.

update locations set lat = "33.5140",lng = "-86.8178" where id=25;

Ubiquiti – AirOS applying changes over ssh

When applying changes over ssh you’ll need to “write” or “save” the changes. Usually you’ll edit the /tmp/system.cfg config file and then save the changes with one of the following commands.

/usr/etc/rc.d/rc.softrestart save
or
cfgmtd -f /tmp/system.cfg -w && reboot

rc.softrestart has some advantages. It does not require the radio to reboot when making changes to things like SNMP or the device name.

It does seem to have issues sometimes with certain changes. The following happened when attempting to replace the whole /tmp/system.cfg with a previous backup config.

XM.v6.1.8# XM.v6.1.8# /usr/etc/rc.d/rc.softrestart save
]--- /tmp/.running.cfg.972
+++ /tmp/.system.cfg.972
@@ -1,110 +1,256 @@
... more random stuff ...
Fast system script build Success.
Fast syslog script build Success.
Fast users script build Success.
Fast poepass script build Success.
Fast resolv script build Success.
do_radio_fast_script: rname wifi0
Unsuported change in radio.1.dfs.status for fast update
Fast radio script build failed
Fixup Startup_list …Done.
Welcome back!
[ubnt@localhost] > 

If you have issues applying changes with the softrestart, you can try it with cfgmtd. Downside is the radio does reboot.

cfgmtd -f /tmp/system.cfg -w && reboot 

You could potentially take the reboot off the end of the above command, but have had random issues in the past where the only way to fix it was a physical reboot. Having the radio reboot after applying the config seems to resolve the issue

Windows 10 – How to “fully” shutdown

Windows 10 by default does a hybrid shutdown which is supposed to make it quicker to start back up.

To fully shutdown you can hold the Shift key down while clicking the shutdown button.

Side note. A Restart will do a full shutdown before starting back up.

More info.

https://www.bleepingcomputer.com/forums/t/625963/details-of-shut-down-vs-restart-please/#entry4079503
https://superuser.com/questions/974553/what-does-shiftshutdown-do-in-windows-10

Install VirtualBox Guest Addition for Kali Linux

Boot up the virtual machince

Insert the “Guest Additions CD Image…” from the Devices menu

In the VM, open up Files/Nautilus or Dolphin and find the CD. Open a terminal in the same directory and execute the auto run script

sudo sh autorun.sh

It should pop up another window to install the guest additions. After it is installed, you’ll need to reboot the VM for the new changes to take effect.

Ubiquiti AirOS 8.5.12 disable Wireless Security

It appears that with one of the latest 8.5 updates that you can no longer change Wireless Security to none from the web interface. Work around is to disable it in a config then apply the config. You can do this from the command line or upload a config under the System tab.

Web Interface

Go to the System tab, backup configuration

open configuration in a text editor and change
“aaa.1.status=enabled” to “aaa.1.status=disabled”

Upload Configuration and Apply to device

Command line

ssh admin@192.168.1.20
sed -i '/aaa.1.status=enabled/aaa.1.status=disabled/g' /tmp/system.cfg
/usr/etc/rc.d/rc.softrestart save

The above should be it, or you can manually edit “/tmp/system.cfg” and change the following line

aaa.1.status=enabled

to

aaa.1.status=disabled

Save changes

/usr/etc/rc.d/rc.softrestart save