modified: README.md

new file:   docs/journald.md

README.md

@@ -16,6 +16,7 @@
   - [Network Configuration](#network-configuration)
     - [hostname / hostnamectl](#hostname--hostnamectl)
     - [static ip](#static-ip)
+  - [System info](#system-info)
   - [System Monitoring Utilities](#system-monitoring-utilities)
     - [btop](#btop)
     - [memory usage by user](#memory-usage-by-user)
@@ -216,6 +217,16 @@ Reiniciar configuração sem reboot de computador
 sudo /etc/init.d/networking restart
 ```
 
+### System info
+
+```bash
+# get distribution
+cat /etc/os-release
+
+# get kernel version
+uname -a
+```
+
 ### System Monitoring Utilities
 
 #### btop

docs/display-managers/sddm.md

@@ -18,3 +18,8 @@ SDDM (Simple Desktop Display Manager) is the default graphical login manager use
 
 - Replaced KDM (KDE Display Manager) starting with KDE Plasma 5.
 - Used by KDE-centric distributions like KDE neon, OpenSUSE KDE, and Fedora KDE Spin.
+
+```bash
+# control ui login at boot
+systemctl start|stop|enabled|disable sddm
+``

docs/journald.md

@@ -0,0 +1,7 @@
+# journald
+
+**get errors from last boot:**
+
+```bash
+journalctl -b -1 -p err
+```