How open oracle DB Linux (After installation) I have just installed Oracle 11gR2 on my Linux Mint Distro (xfce). All worked fine, and I was able to acces to 

https://localhost:1158/em [Erreur 102 (net::ERR_CONNECTION_REFUSED) ]


I rebooted my PC and tried to reopen the page but this time I am unable to open it. 

I am not so expert in Linux but could that be a problem of acces permission ?

How could I resolve this issue? 

Thank you.
First edit your /etc/oratab changing N to Y like that:

orcl:/u01/app/oracle/product/11.2.0/dbhome_1:N


Must be change to Y:

orcl:/u01/app/oracle/product/11.2.0/dbhome_1:Y


Then to start you must use the dbstart script like that: 

export ORACLE_HOME=youroraclehome
su oracle -c "$ORACLE_HOME/bin/dbstart $ORACLE_HOME"


Where "oracle" in the "su" command is the name of the user you used to install oracle. 

This will up all oracle essential services including the https port 1158 (and you can put that in an auto-start script) 

And to stop it: 

export ORACLE_HOME=youroraclehome
su oracle -c "$ORACLE_HOME/bin/dbshut $ORACLE_HOME" 


And to backup it (dump) ;-)

export ORACLE_HOME=youroraclehome
$ORACLE_HOME/bin/exp file=mybackup.dmp full=y 


Remember to test your backup before thinking its working.