Category: Linux

When Red Hat, CentOS’s Linux parent company, announced it was “shifting focus from CentOS Linux, the rebuild of Red Hat Enterprise Linux (RHEL), to CentOS Stream, which tracks just ahead of a current RHEL release.” Many CentOS screamed in protest on social media. CentOS co-founder, Gregory Kurtzer, heard them and announced he’d create his own RHEL clone and CentOS replacement: Rocky Linux

Read more information here


Red Hat, CentOS’s Linux parent company, announced it was “shifting focus from CentOS Linux, the rebuild of Red Hat Enterprise Linux (RHEL), to CentOS Stream, which tracks just ahead of a current RHEL release.” In other words, CentOS will no longer be a stable point distribution but a rolling release Linux distribution. CentOS users are ticked off.

Read the full article here


I setup Node-red to use HTTPS and everything works fine. All HTTPS requests go to default port of Node-red.  Today i need to setup a communication with a client that not support HTTPS, just HTTP.

The solution i found was to setup Nginx as reverse proxy.  Nginx receives the HTTP requests and then forward them to Node-red.

On my Nginx server i just add the following lines

server {
listen 80;
location /reddata {
proxy_pass https://<ipaddress>:port/reddata;



IoT Linux

Today i upgrade one server to Domino 11.0.1 from Domino 11.0 on linux.  When the server starts the HTTP  the console show the error bellow:


[103028:000002-00007F2CD562E740] 06/18/2020 10:40:45 AM JVM: Java Virtual Machine initialized.
[103028:000002-00007F2CD562E740] 06/18/2020 10:40:45 AM HTTP Server: Java Virtual Machine loaded
[103028:000002-00007F2CD562E740] 06/18/2020 10:40:50 AM HTTP JVM: java.lang.reflect.InvocationTargetException
[103028:000002-00007F2CD562E740] 06/18/2020 10:40:50 AM HTTP JVM: at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
[103028:000002-00007F2CD562E740] 06/18/2020 10:40:50 AM HTTP JVM: at sun.reflect.NativeMethodAccessorImpl.invoke(
[103028:000002-00007F2CD562E740] 06/18/2020 10:40:50 AM HTTP JVM: at sun.reflect.DelegatingMethodAccessorImpl.invoke(
[103028:000002-00007F2CD562E740] 06/18/2020 10:40:50 AM HTTP JVM: at java.lang.reflect.Method.invoke(
[103028:000002-00007F2CD562E740] 06/18/2020 10:40:50 AM HTTP JVM: at
[103028:000002-00007F2CD562E740] 06/18/2020 10:40:50 AM HTTP JVM: at
[103028:000002-00007F2CD562E740] 06/18/2020 10:40:50 AM HTTP JVM: at
[103028:000002-00007F2CD562E740] 06/18/2020 10:40:50 AM HTTP JVM: at java.lang.ClassLoader.loadClass(
[103028:000002-00007F2CD562E740] 06/18/2020 10:40:50 AM HTTP JVM: at
[103028:000002-00007F2CD562E740] 06/18/2020 10:40:50 AM HTTP JVM: Caused by:
[103028:000002-00007F2CD562E740] 06/18/2020 10:40:50 AM HTTP JVM: java.lang.ClassNotFoundException: No class loader available for the bundle: [226]
[103028:000002-00007F2CD562E740] 06/18/2020 10:40:50 AM HTTP JVM: at org.eclipse.osgi.internal.framework.EquinoxBundle.loadClass(


The solution was to delete all content of the folder /opt/lotus/notes/latest/linux/osgi/shared/eclipse/plugins and run the installer again.

Domino Linux

You need A Fully Qualified Domain Name (FQDN) pointing to a dedicated IP address of the webserver.
This needs to be configured by your DNS administrator or provider.

1 – Install Certbot in Centos 8

sudo curl -O
chmod 0755 /usr/local/bin/certbot-auto

2 – Configure Nginx server_name on nginx.conf

Edit nginx.conf an change the variable server_name to the same FQDN
of your server for example: server_name;

3 – Run the certbot command:

Execute sudo /usr/local/bin/certbot-auto –nginx and follow the instructions

Test if your Nginx server using https://<server_name>

IoT Linux web

I am creating a server (Centos 8) to develop a system that will use an application using REACT as a front end to show data from different sensors. I will use NGINX as a webserver and Node-red as a back end. In this first post I describe how to install NGINX.

Install nginx package using the yum command on CentOS 8:

sudo yum update
sudo yum install nginx

Update firewall settings and open TCP port 80 and 443. Run:

sudo firewall-cmd –permanent –zone=public –add-service=https –add-service=http
sudo firewall-cmd –reload

Enable nginx service by running systemctl command so that it starts at server boot time:

sudo systemctl enable nginx

start the service, run:

sudo systemctl start nginx

Commands to start/stop/restart nginx server

Run command as per your needs.

sudo systemctl start nginx  <– start the server ##
sudo systemctl stop nginx  <– stop the server ##
sudo systemctl restart nginx  <– restart the server ##
sudo systemctl reload nginx  <– reload the server ##
sudo systemctl status nginx  <– get status of the server ##

You must open and enable port 80 and 443 using the firewall-cmd command:

sudo firewall-cmd –permanent –zone=public –add-service=http –add-service=https
sudo firewall-cmd –reload
sudo firewall-cmd –list-services –zone=public

Now nginx is installed. Bellow are some important directories (defaults) i

Config directory – /etc/nginx/
Maibn global config file – /etc/nginx/nginx.conf
TCP ports opened by Nginx – 80 (HTTP), 443 (HTTPS)
Default web document root directory – /usr/share/nginx/html
Access log file – /var/log/nginx/access.log
Error log file – /var/log/nginx/error.log

IoT Linux web

Command line tools are always welcome.  Today i need to setup my MAC to work with IBM Cloudant

Install curl on your MAC if you haven’t done it yet.

1 – You need to setup the Cloudant DB using your IBM Cloud account.

2 – Go to service credentials and get your username, password and hostname

"username": "xxxx-xxx-xxx-bluemix",
"password": "12345678901234567890",
"host": ""

3 – Test the connection

curl –v –u xxxx-xxx-xxx-bluemix ''

The command will prompt for the password: 12345678901234567890

You will see a lot off lines but pay attention on the line Authorization: Basic. This will be used to setup acurl (authorized curl) to avoid type the password every time you use curl.

* Using HTTP2, server supports multi-use
* Connection state changed (HTTP/2 confirmed)
* Copying HTTP/2 data in stream buffer to connection buffer after upgrade: len=0
* Server auth using Basic with user ‘xxxx-xxx-xxx-bluemix’
* Using Stream ID: 1 (easy handle 0x7fabd0805800)
> GET / HTTP/2
> Host:
> Authorization: Basic asddadasdDASDdaDadaDSERQERQRQERQEDSGSFDGSFDG==

4 – Edit the .bash_profile or .bashrc file in any text editor. For example, from the command line, issue the following command:
open –e .bash_profile

5 – Add the following line to the file, then save the file.
alias acurl="curl -s --proto '=https' -g -H 'Authorization: Basic asddadasdDASDdaDadaDSERQERQRQERQEDSGSFDGSFDG=='"

6 – On the terminal run : source .bash_profile

7 – Issue a command using the new alias. For example, issue a command to view your account information.
acurl -X GET ''

TIP: The hostname is not friendly you can edit your hosts file and create an alias:

On MAC terminal type: sudo vi /etc/hosts

ping your hostname to get the ip address

add a line like this one bellow:

<ip address>  xxxx-xxx-xxx

Save the hosts file

test the connection

acurl -X GET '


Linux MAC

To install atop on Centos you need to enable EPEL Repository

## RHEL/CentOS 7 64-Bit ##
# wget
# rpm -ivh epel-release-7-9.noarch.rpm

Use yum install atop to install on your server.

More information on this link


Yesterday i start to setup some new servers and need to install several libraries on Centos 7

Yum is the first option and when i start a command like yum install <anylib> i got several erros and yum was locked.

See this short video and solve the problem.


Two days ago my NAS WD My Book Live  died. I think because an energy problem.  I bought an USB to SATA adapter and follow the instructions bellow.

The steps worked for a My Book Live 3TB. You need to open and disassembly and extract the HD.  If data partition is not ok, you will loose all data.

1) Download the virgin disk image (02.41.05-034) (203MB) from!FZkASQ6T!P3DMWzaOn62jSrG4SECtIDeJeLYEdmz6w6kR9it8U68599

2) Extract with 7-zip and you should have a file called mybook3tb.img

3) Format an 8GB+ thumbdrive or external usb hard drive to NTFS and copy mybook3tb.img to it

4) Download SystemRescueCd and burn it to a CD

5) Shut down your computer and remove the cable from your computers hard drive so we don’t erase it by mistake  ### Verify your discs on gparted before proceed and write down the names of /dev/sd…  ####

6) Hook up your MyBookLive to a SATA port on your motherboard or buy an eSATA to SATA cable or dock and hook up the drive that way. You can try a USB to SATA cable but success rates vary

7) Turn on your computer and tell it to boot from the CD drive

8) When the system rescue cd menu comes up, select to “directly start the graphical environment”

9) Open gparted and check to see where your MyBookLive shows under. In my case it shows up under /dev/sda
The drive should contain several EXT3 partitions and a rather large EXT4 partition

If your drive shows up under sdb, sdc, sdd etc.  just substitute the proper name for the drive when getting to
dd if=/mnt/usb/mybook3tb.img of=/dev/sda bs=1M (DON’T ENTER THIS COMMAND YET)

Now in gparted check to see where your thumbdrive shows up. In my case it shows up under /dev/sdb1
If it shows up under sdc1, sdd1, sde1, etc.  just substitute the proper name for the drive when getting to
mount -t ntfs /dev/sdb1 /mnt/usb (DONT ENTER THIS COMMAND YET)

10) In terminal type the commands below (Make sure you change sdb1 (For the thumbdrive or usb hard drive) and sda (for the MBL hard drive) to whatever they show up as in GPARTED)

mkdir /mnt/usb
mount -t ntfs /dev/sdb1 /mnt/usb
dd if=/mnt/usb/mybook3tb.img of=/dev/sda bs=1M

11) Look for any errors in the terminal window (output should look similar to below)
4420+0 records in
4420+0 records out

12) Logout of the SystemRescue CD and shut down the computer

13) Hook up the pcb to the MyBookLive hard drive and screw it down with 2 screws for now and then hook up the ethernet and power cord and try booting the drive again without putting it back in the case

14) Now from the dashboard do a Quick Factory restore to format the data partition

15) When the quick factory restore is complete power down the MyBookLive

16) Put the drive back together as you are done!

I copied from the link





Linux will turn 25 years old on August 25, the day Linus Torvalds sent out his fateful message asking for help with a new operating system. “I’m doing a (free) operating system (just a hobby, won’t be big and professional like gnu) for 386(486) AT clones. This has been brewing since april, and is starting to get ready. I’d like any feedback on things people like/dislike in minix, as my OS resembles it somewhat (same physical layout of the file-system (due to practical reasons) among other things),” he wrote in the comp.os.minix message board. And the rest, as they say, is history


My MacBook died yesterday. I am waiting the repair.
Now working with my Ubuntu laptop. Some applications must be installed.
Atom was very easy.

Open a terminal window and run the following:

sudo add-apt-repository ppa:webupd8team/atom
sudo apt-get update
sudo apt-get install atom