As a new operating system is launched, an expectation is created that it has been added, improved or eliminated at both the development and administrative levels . In the case of Linux distributions, with each update drastic changes are executed, always focused on guaranteeing the total integrity of the user at the level of applications, processes and services.. 
   Debian has just released version 9.4 which has some changes compared to its predecessor and today in TechnoWikis we will see what changes it includes and how we can upgrade to this new version in a simple way. 
   
    1.  What's new in Debian 9.4 
  Its official announcement was on March 10, 2018 and Debian 9.4 has the name stretch code. This release of Debian 9.4 has focused on adding corrections for security problems and we must be aware and clarify that this is a new update but not a new edition, so we have worked more to improve Debian packages. 
 This stable Debian 9.4 update adds some important fixes to the following system packages: 
   The obsolete version of the subscription contract is solved 
  acme-tiny 
      The missing dependency is added in python-zeitgeist 
  activity-log-manager 
      The creation of tasks and appointments is corrected 
  agenda.app 
      The feature file has been moved to / usr / share / apparmor-features and the AppArmor function is set in the Stretch core 
    apparmor 
      The apt configuration has been moved at the time of removal and is reinstalled 
  auto-apt-proxy 
      The missing dependency is added in gir1.2-gtk-3.0 
  cappuccino 
      Python3 dependencies are corrected 
  cerealizer 
      A new upstream version is included 
  clamav 
      Works properly with SELinux context system_cronjob_t transition system jobs and stops relying on specific refpolicy identifiers 
  cron 
      A new upstream version is added 
  Dbus 
      It comes with Chromium Webbrowser preconfiguration on the entire system to automatically detect HTTP proxy settings through WPAD 
  debian-edu-config 
      Upgrade to the Bump Linux kernel version from 4.9.0-4 to 4.9.0-6 
  Debian-installer 
      Repair the architecture-based filter for driver installation 
  Directfb 
      Update to the new stable point version 
  Dpdk 
    We can see that most of the work done in Debian 9.4 has been to correct packages. Some packages that were removed in this new version have been: 
      To see in detail all updated or deleted packages, we can visit the following official Debian link: 
      Debian  
    Debian architectures support 
  This new version of Debian 9.4 will be supported by the following architectures: 
 -  32 (i386) and 64 (amd64) bit architectures 
  
    -  ARMv7 (EABI hard-float ABI, armhf) 
  
  -  MIPS (mips (big-endian) and mipsel (little-endian)) 
  
  -  64-bit little-endian MIPS (mips64el) 
  
  -  64-bit little-endian PowerPC (ppc64el) 
  
        Now, let's see how to upgrade to this new version of Debian.. 
   
      2.  How to check the current Debian version and update the system 
  Step 1 
  The first step to take is to validate which version of Debian 9 we currently have, for this we execute the following: 
 lsb_release -a join me -mrs 
 We can validate that we have Debian version 9.1. 
 
 
  Step 2 
  Now, the next step will be to update the Debian 9 packages by running the following line: 
 apt-get update 
  
 
  Step 3 
  Then we execute the following: 
 apt-get dist-upgrade 
 There we enter the letter S to proceed to download all the updates for Debian where the update to version 9.4 is included.  
 
 
  Step 4 
  Once this process is finished we proceed to restart the system by executing: 
 reboot 
 Finally, when the system is loaded again we will execute the following: 
 join me -mrs lsb_release -a w 
  
 
  We can validate that the system has been updated to Debian version 9.4. It's that simple to upgrade to this new version of this great Linux distribution.