1. Stop all the OMS:

cd <OMS_HOME>/bin
emctl stop oms

emctl stop oms -bip_only
emctl extended oms jvmd stop –all

emctl extended oms adp stop -all


2.修改SYSMAN密码
cd <OMS_HOME>/bin
emctl config oms -change_repos_pwd -use_sys_pwd -sys_pwd <sys user password> -new_pwd <new sysman password>

具体例子：
  比如要修改为sztech_4U

   ./emctl config oms -change_repos_pwd -use_sys_pwd -sys_pwd oracle_4U -new_pwd sztech_4U



[oracle@omsserver bin]$ ./emctl config oms -change_repos_pwd -use_sys_pwd -sys_pwd oracle_4U -new_pwd sztech_4U
Oracle Enterprise Manager Cloud Control 13c Release 5  
Copyright (c) 1996, 2021 Oracle Corporation.  All rights reserved.

Changing passwords in backend ...
Passwords changed in backend successfully.
Updating repository password in Credential Store...
Successfully updated Repository password in Credential Store.
Restart all the OMSs using 'emctl stop oms -all' and 'emctl start oms'.
Successfully changed repository password.

3. 停止所有管理服务并重启OMS:
   emctl stop oms -all
   emctl start oms


[oracle@omsserver bin]$ ./emctl stop oms -all
Oracle Enterprise Manager Cloud Control 13c Release 5  
Copyright (c) 1996, 2021 Oracle Corporation.  All rights reserved.
Stopping Oracle Management Server...
WebTier Successfully Stopped
Oracle Management Server Already Stopped
AdminServer Successfully Stopped
Oracle Management Server is Down
JVMD Engine is Down


[oracle@omsserver bin]$ ./emctl start oms
Oracle Enterprise Manager Cloud Control 13c Release 5  
Copyright (c) 1996, 2021 Oracle Corporation.  All rights reserved.
Starting Oracle Management Server...
WebTier Successfully Started
Oracle Management Server Already Started
Oracle Management Server is Up
JVMD Engine is Up



[oracle@omsserver bin]$ ./emctl status oms
Oracle Enterprise Manager Cloud Control 13c Release 5  
Copyright (c) 1996, 2021 Oracle Corporation.  All rights reserved.
WebTier is Up
Oracle Management Server is Up
JVMD Engine is Up


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