Using Services to Automatically Start PDBs in a RAC Environment

This demonstration shows you the effect of stopping and starting manually created services on your PDBs in a RAC environment. This is to demo you do not need to create triggers to automatically start PDBs in a RAC environment.
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[@anzodefotouni5618]

Please help me in solving this issue:
After installation of both nodes server, everything worked fine, but three days later
I tried to start my database, but I received the following errors (on both nodes):
[oracle@orac2 ~]$ sqlplus / as sysdba
SQL*Plus: Release 12.2.0.1.0 Production on Thu Dec 14 13:43:45 2017
Copyright (c) 1982, 2016, Oracle. All rights reserved.
Connected to an idle instance.
SQL> startup
ORA-01078: failure in processing system parameters
LRM-00109: could not open parameter file '/u01/app/oracle/product/12.2.0.1/db_1/dbs/initcdbrac2.ora'
SQL>
When I cd to the dbs directory the initcdbrac2.ora is missing
[oracle@orac1 dbs]$ ll
total 8
-rw-rw---- 1 oracle dba 1544 Dec 11 02:27 hc_CDBRAC1.dat
-rw-r--r-- 1 oracle dba 3079 May 15 2015 init.ora
[oracle@orac1 dbs]$
Note I used ASM for storage and the following is the the bash_profile
# Oracle Settings
export TMP=/tmp
export TMPDIR=$TMP
export ORACLE_HOSTNAME=orac2.XXXXXX.com
export ORACLE_UNQNAME=CDBRAC
export ORACLE_BASE=/u01/app/oracle
export GRID_HOME=/u01/app/12.2.0.1/grid
export DB_HOME=$ORACLE_BASE/product/12.2.0.1/db_1
export ORACLE_HOME=$DB_HOME
export ORACLE_SID=cdbrac2
export ORACLE_TERM=xterm
export BASE_PATH=/usr/sbin:$PATH
export PATH=$ORACLE_HOME/bin:$BASE_PATH
export LD_LIBRARY_PATH=$ORACLE_HOME/lib:/lib:/usr/lib
export CLASSPATH=$ORACLE_HOME/JRE:$ORACLE_HOME/jlib:$ORACLE_HOME/rdbms/jlib
alias grid_env='. /home/oracle/grid_env'
alias db_env='. /home/oracle/db_env'
here is oratab where the database entry s no more present:
[oracle@orac2 ~]$ cat /etc/oratab
#Backup file is /u01/app/12.2.0.1/grid/srvm/admin/oratab.bak.orac2 line added by Agent
# .
.
.
# The first and second fields are the system identifier and home
# directory of the database respectively. The third field indicates
# to the dbstart utility that the database should , "Y", or should not,
# "N", be brought up at system boot time.
#
# Multiple entries with the same $ORACLE_SID are not allowed.
#
+ASM2:/u01/app/12.2.0.1/grid:N # line added by Agent
[oracle@orac2 ~]$ srvctl start database -db cdbrac1 -eval
PRCD-1120 : The resource for database cdbrac1 could not be found.
PRCR-1001 : Resource ora.cdbrac1.db does not exist
Please I need help as I have no backup.