Development Scopes and declaration of variables with var, let and const in JavaScript In JavaScript there are two main scopes where to locate the variables, and these scopes determine the accessibility to these variables:* global * local: no están accesibles desde el scope global A variable in
IT infrastructure and architecture How to disable systemd-resolved in linux ubuntu 18.04 and 20.04... and how to ensure that your resolv.conf does not update on each reboot In the latest distributions of ubuntu 18.04 and 20.04 that I used have activated the sysemd-resolved that I do not like at all, especially for not allowing me a more particular
IT infrastructure and architecture How to export a private key to RSA PEM format with ssh-keygen To manage authentication to ssh or sftp services I always do it through ssh keys, and I usually generate them with the following ssh-keygen command:ssh-keygen -t rsa -b 4086 -C usersftp@localhost
Development openssl - Linux man page with examples: example with command s_client and options showcerts, servername y connect Example with the command 's_client' of openssl to see the certificates of a domain. With the 'connect' option we specify the IP or DNS of the server we want to consult, the
Development openssl - Linux man page with examples NAME openssl - OpenSSL command line tool SYNOPSIS openssl command [ command_opts ] [ command_args ] openssl list [ standard-commands | digest-commands | cipher-commands | cipher-algorithms | digest-algorithms | public-key-algorithms] openssl no-XXX [ arbitrary options ] DESCRIPTION OpenSSL is a cryptography toolkit implementing
IT infrastructure and architecture How install docker-compose on ubuntu 20.04 armhf in Raspberry Pi 3 B In the repository of the official list of versions in githab:https://github.com/docker/compose/releasesthere are no versions for armhf. Well, I haven't found them.Therefore, to install docker-compose on a
IT infrastructure and architecture How install docker on ubuntu 20.04 armhf in Raspberry Pi 3 B Run the command:sudo apt install docker.io Once installed we check the version:docker --version Which in my example returns:operatorvm@vmrp01ubuntu2004web:~$ docker --version Docker version 20.10.2, build 20.10.
IT infrastructure and architecture How to make a user sudo in ubuntu 20.04 With a root user or with sudo privileges execute the following:sudo adduser username sudo Example:ubuntu@vmrp01ubuntu2004web:~$ sudo adduser operatorvm sudo Adding user `operatorvm' to group `sudo' ... Adding user operatorvm to group
Development Using curl: proxy calls with user and password to URLs with basic authentication The way to use curl for calls to a URL that have basic authentication through a proxy with per-user authentication and password is as follows:curl -v -o /dev/null -x http://myproxy.
Bugs and errors fix How to fix error problem with installed package podman and buildah installed docker-ce in CentOS If you try to install on a CentOS 8 docker-ce and you get the following error:[operatorfeitam@localhost ~]$ sudo yum install docker-ce docker-ce-cli containerd.io Last metadata expiration check: 0:03:31 ago
IT infrastructure and architecture How to create a user on Ubuntu 18.04.3 LTS armv71 on Raspberry Pi 2 Model B+ encapsulated to only access by SFTP In this entry we will see how we create a user on an Ubuntu OS 18.04.3 LTS armv71 on a Raspberry Pi 2 Model B+ that can only access a specific
Bugs and errors fix How to fix Microsoft Office hyperlink problem with errors "Cannot locate the Internet server or proxy server" and "Cannot open the specified file" In some Microsoft Office installation sometimes when you press Ctrl+click on hyperlinks you get the error message "Cannot locate the Internet server or proxy server" (in Spanish the message that appears is
IT infrastructure and architecture Backup recommendations in Windows 10 I am going to detail the backup recommendations to follow on a Windows 10. They are logical recommendations that can be followed in the same way on other operating systems like Ubuntu or
IT infrastructure and architecture How fix error Impossible to lookup any SSHKeyStore named instance: org.jboss.weld.exceptions.WeldException: WELD-000049: Unable to invoke public void org.uberfire.ssh.service.backend.keystore.impl.storage.DefaultSSHKeyStore.init() in jBPM KIE Server Today I encountered the following error that prevented me from deploying the jBPM application to the JBoss Wildfly 19.1.0 server in the business-central.war drop-down:22:04:40,186 INFO [org.
Development How to implement an angular custom pipe in a JHipster application Let's detail the steps to create a custom pipe in a JHipster 6.10.5 application with angular 10.0.0.We will define a pipe that converts a string into a kebab-case
Development How fix errors "No X11 DISPLAY variable was set" and "An error occurred: Can't connect to X11 window server using 'x.x.x.x:0.0' as the value of the DISPLAY variable" in ssh sesion with X11 forwarding I use Windows 10 as a working operating system but almost all the development operation and system architecture is done through Ubuntu and CentOS computers that I access by ssh, VNC or RDP
Development How to install kubectl with multiple versions to be able to manage different versions of kubernetes cluster with update-alternatives on ubuntu 20.04 I work with several clusters of kubernetes and each of it is of a specific version, therefore I need to have different kubectl. To manage this what I do is access https://github.
Security How fix error could not verify 'ssh-ed25519' host key In some integrations with SFTP, for example from NIFI, I have often encountered the following error message:ListSFTP[id=a9f3e106-0177-1000-2137-90dcc74fc40e] Failed to perform listing on remote host due to Could not verify 'ssh-ed25519'
Development Avoiding unexpected errors: sudo with meta characters like asterisk, question mark and others When a command is executed with 'sudo' the metacharacters except the $ are escaped. This causes that command like the following that we think should work correctly gives unexpected problems:sudo ls -t /etc/
Development How to add to apache2 on Ubuntu 20.04 a new site configured to avoid cross domain errors using ProxyPass and ProxyPassReverse In apache2 on Ubuntu, for example 20.04, if you want to add a new site or configuration for a site you must first define the site in a configuration file to be
IT infrastructure and architecture How to fix error when booting Ubuntu 20.04 UNEXPECTED INCONSISTENCY RUN fsck MANUALLY On a laptop with Ubuntu 20.04 without battery after having a power outage I had the following error when booting:blk_update_request: I/O error, dev sda, secto 1871712792 op 0x0:
IT infrastructure and architecture How to fix CentOS 8 boot error: Metadata corruption detected at xfs_agi_verify. Unmount and run xfs_repair In this entry I detail how I managed to fix this problem that I have had in CentOS 8: 'Metadata corruption detected at xfs_agi_verify. Unmount and run xfs_repair. First 128
IT infrastructure and architecture How to implement a CDC (change data capture) of a database Hana table using Apache Kafka and the kafka-connect-sap connector in incremental mode to a PostgreSQL database This entry details the implementation of a CDC (change data capture) of a Hana database table using triggers at the source database layer to identify the insert, update, and delete changes to that
Development How to update node with npm and the "n" module Whenever I have to update the node version I do it using npm along with module "n" although there are other options, but this one seems to me the most comfortable.Before upgrading
Development How to fix the Error: EACCES: permission denied, unlink '/usr/local/bin/jhipster' when installing generator-jhipster library node with npm I found this error when creating a jhipster project with npm, and first trying to install the node generator-jhipster library with:npm install -g generator-jhipster The error detail is as follows:[operatorfeitam@dev01