1.修改/etc/oratab文件

[oracle@node01:/home/oracle]$ cat /etc/oratab
#
# This file is used by ORACLE utilities.  It is created by root.sh
# and updated by either Database Configuration Assistant while creating
# a database or ASM Configuration Assistant while creating ASM instance.

# A colon, ':', is used as the field terminator.  A new line terminates
# the entry.  Lines beginning with a pound sign, '#', are comments.
#
# Entries are of the form:
#   $ORACLE_SID:$ORACLE_HOME:<N|Y>:
#
# 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.
#
#
cxmtdb:/u01/app/oracle/product/19.3.0/db:Y

2.修改/etc/rc.local文件
vim /etc/rc.local

#OracleBegin
su oracle -lc "/u01/app/oracle/product/19.3.0/db/bin/lsnrctl start"
su oracle -lc /u01/app/oracle/product/19.3.0/db/bin/dbstart
#OracleEnd

3.给rc.local文件授权

[root@node01:/root]$ chmod 755 /etc/rc.local

4.
注：在oracle 12c以及以后的数据中，不能启动内部的pdb库，可以写一个触发器如下：

create trigger open_dev
after startup on database
begin
execute immediate ‘alter pluggable database pdb01,pdb02,pdb03 open’;
end;
/