Raspberry, Ubuntu and Megatools

Posted on 17 June 2020 by kosmas

To install megtools (command line utilities for Mega.nz), in your raspberry with ubuntu installed follow the steps below (thanks to the instructions from here: https://www.instructables.com/id/Descarga-archivos-de-Mega-con-Raspberry-Pi/)

Install the necessary packages

sudo apt-get -y install build-essential libglib2.0-dev libssl-dev libcurl4-openssl-dev libgirepository1.0-dev 

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						sudo apt-get -y install build-essential libglib2.0-dev libssl-dev libcurl4-openssl-dev libgirepository1.0-dev

You may also need to add some additional packages if there is an error about the documentation.

Get the latest source code from https://megatools.megous.com

wget https://megatools.megous.com/builds/megatools-1.10.3.tar.gz

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						wget https://megatools.megous.com/builds/megatools-1.10.3.tar.gz

Compile and install them

tar xvfz megatools-1.10.3.tar.gz
cd megatools-1.10.3
./configure
make
sudo make install
sudo ldconfig

				
					
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						tar xvfz megatools-1.10.3.tar.gz
cd megatools-1.10.3
./configure
make
sudo make install
sudo ldconfig

					

			

Add your Mega account credentials in ~/.megarc like:

[Login]
Username = my_mega@email
Password = mypassword

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						[Login]
Username = my_mega@email
Password = mypassword

use the mega tools commands (megacopy, megals, megaget etc.

Erlang and Elixir with asdf in Raspberry 4 with Ubuntu 20.04

Posted on 12 June 2020 by kosmas

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To install the latest/current versions of erlang (23.0.2) and elixir (1.10.3), follow the instructions below:

Install asdf ( full instructions https://asdf-vm.com/#/core-manage-asdf-vm):

git clone https://github.com/asdf-vm/asdf.git ~/.asdf --branch v0.7.8

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						git clone https://github.com/asdf-vm/asdf.git ~/.asdf --branch v0.7.8

Add the following two lines in your ~/.bashrc file:

# Add asdf version manager 
. $HOME/.asdf/asdf.sh
. $HOME/.asdf/completions/asdf.bash

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						# Add asdf version manager 
. $HOME/.asdf/asdf.sh
. $HOME/.asdf/completions/asdf.bash

Reload/Source your bash file with

source ~/.bashrc

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						source ~/.bashrc

Install the erlang plugin

asdf plugin add erlang

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						asdf plugin add erlang

If you get the following warnings:

...
Extracting source code
Building Erlang/OTP 23.0.2 (asdf_23.0.2), please wait...
WARNING: It appears that a required development package 'libssl-dev' is not installed.
WARNING: It appears that a required development package 'automake' is not installed.
WARNING: It appears that a required development package 'autoconf' is not installed.
WARNING: It appears that a required development package 'libncurses5-dev' is not installed.
Configure failed.
...

				
					
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						...
Extracting source code
Building Erlang/OTP 23.0.2 (asdf_23.0.2), please wait...
WARNING: It appears that a required development package 'libssl-dev' is not installed.
WARNING: It appears that a required development package 'automake' is not installed.
WARNING: It appears that a required development package 'autoconf' is not installed.
WARNING: It appears that a required development package 'libncurses5-dev' is not installed.
Configure failed.
...

					

			

Install the missing packages:

sudo apt install libssl-dev automake autoconf libncurses5-dev

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						sudo apt install libssl-dev automake autoconf libncurses5-dev

Install latest erlang version:

asdf install erlang latest
...
Erlang/OTP 23.0.2 (asdf_23.0.2) has been successfully built
...

				
					
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						asdf install erlang latest
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Erlang/OTP 23.0.2 (asdf_23.0.2) has been successfully built
...

					

			

Set it up globally (if you want):

asdf global erlang 23.0.2

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						asdf global erlang 23.0.2

Add elixir plugin:

asdf plugin add elixir

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						asdf plugin add elixir

Install latest elixir version (1.10.3):

asdf install elixir latest

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						asdf install elixir latest

Set it up globally:

asdf global elixir 1.10.3-otp-23

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						asdf global elixir 1.10.3-otp-23

Finally you can also install the latest Phoenix version (1.5.3):

mix archive.install hex phx_new 1.5.3

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						mix archive.install hex phx_new 1.5.3

WiFi, Raspberry Pi 4 B, Ubuntu 20.04

Posted on 10 June 2020 by kosmas

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After installing an image of the Ubuntu server on the Raspberry 4, the wifi is not automatically configured after the initial book.

In order to be able to use the WiFi follow the steps described below for setting up your wifi in your SD card, and then reboot your raspberry (make sure that the indentation in the yaml file is correct, and also your WiFi access point is enclosed in quotes):

https://ubuntu.com/tutorials/how-to-install-ubuntu-on-your-raspberry-pi#3-wifi-or-ethernet

restarting X Window Server from command line in linux

Posted on 2 June 2020 by kosmas

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To restart your X Window Server from the command line in linux, without affecting any non-graphical programs (but losing any unsaved information in your graphical user interface programs), you can use the following:

sudo systemctl restart display-manager

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						sudo systemctl restart display-manager

Get a list of your Route53 subdomains using aws cli docker image

Posted on 13 March 2020 by kosmas

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Problem

You would like to have a list of your subdomains for a specific domain (hosted zone), that are hosted in Amazon’s Route 53.

Solution

You can install the aws cli docker image from here https://github.com/cgswong/docker-aws if you don’t want to install the aws cli in your computer.

You can afterwards start the container with:

docker run -it cgswong/aws:latest

Then configure it by running the following and adding your credentials and zone:

efe9881d4fd:/tmp# aws configure
 AWS Access Key ID [None]: aws_access_key_id
 AWS Secret Access Key [None]: aws_secret_access_key
 Default region name [None]: eu-central-1
 Default output format [None]:

Then run the first command to get a list of the hosted zones and get the id of the hosted zone you want to find the subdomains for:

3efe9881d4fd:/tmp# aws route53 list-hosted-zones
{
    "HostedZones": [
        {
            "ResourceRecordSetCount": 2, 
            "CallerReference": "RISWorkflow-RD:xxxxx", 
            "Config": {
                "Comment": "HostedZone created by Route53 Registrar", 
                "PrivateZone": false
            }, 
            "Id": "/hostedzone/HOSTEDZONEID", 
            "Name": "domain.net."
        },

Then pick the HOSTEDZONEID and run the following to get a list of subdomains for that domain:

3efe9881d4fd:/tmp# aws route53 list-resource-record-sets --hosted-zone="HOSTEDZONEID" | grep "Name" | uniq

   "Name": "alpah.domain.com.",                                                                                                                                                                                                                                             
   "Name": "beta.domain.com.",                                                                                                                                                                                                                                       
   "Name": "lamda.domain.com.",
......

Find devices with their IPs in your local network

Posted on 10 March 2020 by kosmas

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Problem

You would like to have a list of IPs or MAC address for the device in your network

Solution

Use the ARP protocol’s command:

$ arp -a

dv1.home (192.168.1.102) at 48:xx:xx:xx:xx:xx [ether] on wlp4s0
dv2.home (192.168.1.127) at a4:xx:xx:xx:xx:xx [ether] on wlp4s0
...

Find your public IP address from linux command line

Posted on 13 January 2020 by kosmas

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Problem

You would like to find out your public IP from the command line without using an online service

Solution

Use dig like the following line (taken from https://www.cyberciti.biz/faq/how-to-find-my-public-ip-address-from-command-line-on-a-linux/):

dig +short myip.opendns.com @resolver1.opendns.com

you could also add it as an alias:

alias myip=”dig +short myip.opendns.com @resolver1.opendns.com”

Get a list for all crontab jobs in a server

Posted on 6 December 2019 by kosmas

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To get a list of all the installed crontab jobs on a server use the following (taken from https://stackoverflow.com/a/134944)

for user in $(cut -f1 -d: /etc/passwd); do echo $user; crontab -u $user -l; done

Find your Thinkpad (X1) model type in linux

Posted on 9 October 2019 by kosmas

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Problem

You would like to find out the exact model from your Thinkpad X1 laptop, by using your linux command line.

Solution

Use the following command:

kosmas:$ sudo dmidecode | grep -A3 '^System Information'
[sudo] password for kosmas: 
System Information
        Manufacturer: LENOVO
        Product Name: 20HRCTO1WW
        Version: ThinkPad X1 Carbon 5th

Stopping autossh process

Posted on 5 September 2019 by kosmas

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To correctly stop an autossh running process use the following (taken from https://superuser.com/a/1008029):

sudo pkill -3 autossh

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Web notebook about thoughts and discoveries in DevOps, SRE, Software Engineering….

Category Archives: linux

Raspberry, Ubuntu and Megatools

Erlang and Elixir with asdf in Raspberry 4 with Ubuntu 20.04

WiFi, Raspberry Pi 4 B, Ubuntu 20.04

restarting X Window Server from command line in linux

Get a list of your Route53 subdomains using aws cli docker image

Problem

Solution

Find devices with their IPs in your local network

Problem

Solution

Find your public IP address from linux command line

Problem

Solution

Get a list for all crontab jobs in a server

Find your Thinkpad (X1) model type in linux

Problem

Solution

Stopping autossh process