Connection to sys /as sysdba hangs

Description:
When I try to connect database using sys /as sysdba database hangs. No response from the database. I tried the below method to solve this issue.
Solution:
Step 1: Tried sqlplus connect " / as sysdba", found that Database hangs.
Step 2: While this connection hangs, opened a different session, issued the following command to find the Oracle related process.
$ps -ef | grep ORACLE_SID
Step 3: Killed the below the Oracle related process using th below command.
kill -9 pid of processess that are connected that are not related to the sysdba connection (pid from Step 2)
Step 4: Now successfully logged into sys/as sysdba session returns SQL prompt, and issued the following
SQL> shutdown abort
SQL> startup restrict
SQL> shutdown immediate
SQL> startup
Step 5: Checkd the database connections as sysdba are successful
$sqlplus "/as sysdba"
SQL> connect / as sysdba