Sysadmin-tasks.md

 ## Sysadmins emails should be added in /etc/aliases
 
 ```
-vi /etc/aliases
+# vi /etc/aliases
 root: admin1@domain.net, admin2@domain.net, admin3@domain.net
 ```
 
 **WHY:**
-
 The server sends emails for the security updates* that have been installed overnight and inform the sysadmins if a reboot is necessary.
 
-* Requires that we have enabled unattended updates
+**REQUIRES:** 
+that we have enabled unattended updates, see how-to:
+https://wiki.debian.org/UnattendedUpgrades
 
 **OPTIONAL:**
-
 In order to receive the latest Debian security advisories, subscribe to the [debian-security-announce](https://lists.debian.org/debian-security-announce/) mailing list.
 
 ## Server reboot
-`shutdown -r +2 `
-# the flag +m will execute the shutdown after 2min. Handy to make sure users can logout before shutting down.
-# the flag -r is for reboot
-alternatives:
+List and save all services currently running in a file with a timestamp in the name, before and after the reboot: 
+```
+# systemctl list-units --type=service --state=running > DD-MM-YY-beforeboot
+``` 
+ref: https://linuxhint.com/list-all-running-services-debian/
+```
+# shutdown -r +2
+```
+* the flag -r is for reboot
+* the flag +m will execute the shutdown after 2min. Handy to make sure users can logout before shutting down
+
+When server is back again, save the list of services and check for differences
+```
+# systemctl list-units --type=service --state=running > DD-MM-YY-aftereboot
+# diff service-<timestamp>-beboreboot DD-MM-YY-afterboot > diff-services
+# less diff-services
+```
+
+**ALTERNATIVES:**
+```
 systemctl reboot
-We didn't find a flag to add specific time, so we opted for the above.
+```
\ No newline at end of file
+We didn't find a flag to add specific time of the reboot execution, so we opted for the `shutdown` command to make sure that we have time to finish any pending tasks we run and to exit the server.
\ No newline at end of file