问题描述：开启PDB时报错ORA-00800、ORA-65054，如下所示：
数据库信息：账务库备库1节点 IP：192.168.133.183 实例名：tmis1 版本：oracle 19.20
1、告警信息
2024-09-10T22:19:44.336563+08:00
Errors in file /u01/app/oracle/diag/rdbms/tmisdg/tmis1/trace/tmis1_vktm_152164.trc  (incident=9280096) (PDBNAME=CDB$ROOT):
ORA-00800: soft external error, arguments: [Set Priority Failed], [VKTM], [Check traces and OS configuration], [Check Oracle document and MOS notes], []
Incident details in: /u01/app/oracle/diag/rdbms/tmisdg/tmis1/incident/incdir_9280096/tmis1_vktm_152164_i9280096.trc
......
2024-09-10T22:20:02.153306+08:00
ORCLPDB(3):Error 65054 during pluggable database ORCLPDB opening in read write 
2024-09-10T22:20:02.153350+08:00
TMISPDB(4):Error 65054 during pluggable database TMISPDB opening in read write 
2024-09-10T22:20:02.153641+08:00
ORCLPDB(3):Errors in file /u01/app/oracle/diag/rdbms/tmisdg/tmis1/trace/tmis1_p000_156773.trc:
ORA-65054: Cannot open a pluggable database in the desired mode.
2024-09-10T22:20:02.153724+08:00
TMISPDB(4):Errors in file /u01/app/oracle/diag/rdbms/tmisdg/tmis1/trace/tmis1_p001_156777.trc:
ORA-65054: Cannot open a pluggable database in the desired mode.
2024-09-10T22:20:02.153783+08:00
Errors in file /u01/app/oracle/diag/rdbms/tmisdg/tmis1/trace/tmis1_p000_156773.trc:
ORA-65054: Cannot open a pluggable database in the desired mode.
2024-09-10T22:20:02.153884+08:00
Errors in file /u01/app/oracle/diag/rdbms/tmisdg/tmis1/trace/tmis1_p001_156777.trc:
ORA-65054: Cannot open a pluggable database in the desired mode.
2024-09-10T22:20:02.154562+08:00
Unable to restore open state for pluggable databases due to the following errors.
2024-09-10T22:20:02.154674+08:00
Errors in file /u01/app/oracle/diag/rdbms/tmisdg/tmis1/trace/tmis1_ora_156353.trc:
ORA-65054: Cannot open a pluggable database in the desired mode.
Physical standby database opened for read only access.

2、解决方案
根据MOS [Doc ID 2718971.1]，确认到该节点$ORACLE_HOME/bin/oradism权限为750.
[oracle@hisdb1 /home/oracle]$ip a | grep 133.183
    inet 192.168.133.183/26 brd 192.168.133.191 scope global bondeth0
[oracle@hisdb1 /home/oracle]$cd $ORACLE_HOME
[oracle@hisdb1 /u01/app/oracle/product/19.0.0.0/dbhome_1]$cd bin
[oracle@hisdb1 /u01/app/oracle/product/19.0.0.0/dbhome_1/bin]$ls -ltr oradism
-rwxr-x--- 1 oracle oinstall 145920 Jun 21  2023 oradism

正常节点该文件权限为4750，如下所示：
[oracle@cblnp /u01/app/oracle/product/19.0.0/dbhome_1/bin]$ls -ltr oradism
-rwsr-x--- 1 root oinstall 145920 Jun 21  2023 oradism
[oracle@cblnp /u01/app/oracle/product/19.0.0/dbhome_1/bin]$  ip a | grep 131
    inet 192.168.133.131/26 brd 192.168.133.191 scope global ebond2.807

[oracle@hisdb2 /u01/app/oracle/product/19.0.0.0/dbhome_1/bin]$ls -ltr oradism
-rwsr-x--- 1 root oinstall 145920 Jun 21  2023 oradism
[oracle@hisdb2 /u01/app/oracle/product/19.0.0.0/dbhome_1/bin]$   ip a | grep 184
    inet 192.168.133.184/26 brd 192.168.133.191 scope global bondeth0
	
小结：因此建议将192.168.133.183节点的$ORACLE_HOME/bin/oradism权限修改为4750，具体指令如下：
[oracle@hisdb1 /home/oracle]$ cd $ORACLE_HOME/bin
[oracle@hisdb1 /home/oracle]$ chmod u+s oradism

3、其它相关查询
-- 异常节点192.168.133.183
[oracle@hisdb1 /home/oracle]$ cat /sys/fs/cgroup/cpu,cpuacct/system.slice/cpu.rt_runtime_us
0
[oracle@hisdb1 /home/oracle]$ cat /sys/fs/cgroup/cpu,cpuacct/user.slice/cpu.rt_runtime_us
0

-- 正常节点 192.168.133.131
[oracle@cblnp /u01/app/oracle/product/19.0.0/dbhome_1/bin]$ cat /sys/fs/cgroup/cpu,cpuacct/system.slice/cpu.rt_runtime_us
0
[oracle@cblnp /u01/app/oracle/product/19.0.0/dbhome_1/bin]$ cat /sys/fs/cgroup/cpu,cpuacct/user.slice/cpu.rt_runtime_us
0	

说明：cpu.rt_runtime_us 参数配置在异常节点和正常节点一致，意味着该参数不用修改.

-- Check the priority of VKTM or LMS* @RDBMS level
[oracle@hisdb1 /u01/app/oracle/product/19.0.0.0/dbhome_1/bin]$ sqlplus / as sysdba

SQL*Plus: Release 19.0.0.0.0 - Production on Wed Sep 11 09:56:31 2024
Version 19.20.0.0.0

Copyright (c) 1982, 2022, Oracle.  All rights reserved.


Connected to:
Oracle Database 19c Enterprise Edition Release 19.0.0.0.0 - Production
Version 19.20.0.0.0

SQL> show pdbs

    CON_ID CON_NAME                       OPEN MODE  RESTRICTED
---------- ------------------------------ ---------- ----------
         2 PDB$SEED                       READ ONLY  NO
         3 ORCLPDB                        READ ONLY  NO
         4 TMISPDB                        READ ONLY  NO
		 
set linesize 680
col Parameter for a30
col "Session Value" for a16
col "Instance Value" for a16
col "Description"  for a30
select a.ksppinm "Parameter", b.ksppstvl "Session Value", c.ksppstvl "Instance Value", a.KSPPDESC "Description" 
  from x$ksppi a, x$ksppcv b, x$ksppsv c 
 where a.indx = b.indx and a.indx = c.indx and a.ksppinm like '_%' and a.ksppinm like '_highest_priority_process%';

Parameter                      Session Value    Instance Value   Description
------------------------------ ---------------- ---------------- ------------------------------
_highest_priority_processes    VKTM             VKTM             Highest Priority Process Name
                                                                 Mask
																 
说明：确认值为"VKTM"，为正确设置的值.

4、总结
此异常场景中，建议将192.168.133.183节点的$ORACLE_HOME/bin/oradism权限修改为4750.