timed out waiting for input: auto-logout

I connected to db node of Exadata and after some idle time I was disconnected from server with the message:

[root@ed02dbadm02 ~]# timed out waiting for input: auto-logout

Connection closed.

As I remember my terminal can stay connected to Exadata all day, many hours.  
Whats the matter ? It is something new ...


Internet explain this behaviour:

Auto-Logout Timeout in SSH

The ssh "timed out waiting for input: auto-logout" messages is generated by ssh upon reaching a auto-logout after an inactivity time specified by the TMOUT environment variable. If this variable is not set your session will not be auto-logged out due to inactivity. If the environment variable is set, your session will be automatically closed/logged out after the amount of seconds specified by the TMOUT variable.

To see if your auto-logout variable is set and/or see what it is set to issue the following command:
 $ echo $TMOUT

Often this value is defined in /etc/profile (globally) or your user's profile (~/.profile or ~/.bash_profile).

To alter the auto-logout amount, set the TMOUT environment variable accordingly:
* TMOUT=600   #set an auto-logout timeout for 10 minutes
* TMOUT=1200  #set an auto-logout timeout for 20 minutes
* TMOUT=   #turn off auto-logout (user session will not auto-logout due to session inactivity)

This value can be set globally (e.g. TMOUT=1200) in the /etc/profile file;