(EDIT 20130917: If you simply need to change the IP address of your OEM server, please review MOS note 1562029.1. The procedure in that note may allow you to change your OEM server’s IP address without following the lengthy process I describe below.)
In order to save power in our data center, I need to migrate my EM12c R3 environment from the host where it currently runs to a new host. I have a simple configuration, with a single OMS, no load balancer, and the repository database runs on the same host as EM12c R3 itself. I also have BI Publisher installed and integrated with EM12c, and a few third party plugins as I’ve detailed elsewhere on this blog. If you use an OS other than Linux x86-64 I suggest you research thoroughly as this procedure may or may not apply to your environment. Further, if you have a multi-OMS setup or use a load balancer, you must read the documentation and adapt the process accordingly to match your system’s needs. Note that I wrote this as I did the migration, live, on my production system, so I have text in a few places showing where I would have done things differently if I knew what to expect in the first place. It all ended up working, but it could have been simpler.
Oracle documents the procedure for this migration in the EM12c Administrator’s Guide, Part VII, section 29, “Backing Up and Recovering Enterprise Manager“. As a first step, my system administrator installed SLES 11 SP3 on the new server and created an account for me along with the ‘oracle’ account for EM12c. I have a 70GB volume to use for the database and OEM binaries, a 1GB volume for the DB control files and a 2GB volume for redo logs supplemented with a 15GB FRA volume to support flashback. Due to our tape backup strategy I use the FRA only for flashback, which we don’t wish to backup, and use a separate volume for RMAN backupsets. To avoid a backup/restore cycle, the volumes holding the database datafiles will just be moved over to the new host on the storage side.
First I will relocate the management repository database to the new host, then complete the process by relocating the OMS.
Relocating the Management Repository Database
I run Oracle Database 126.96.36.199, Enterprise Edition, plus PSU Jul 2013. Rather than installing the database software from scratch and patching it, I will clone the existing Oracle home to the new server. Unfortunately I cannot use EM12c to do the cloning, as cloning via EM12c requires a management agent on the new host. The software-only install of EM12c that I will run later installs a management agent as part of the process and I do not wish these two to conflict, so I do not want to install an agent on the new host at this time.
I will clone the database home according to the procedure in Appendix B of the 11gR2 database documentation. You should review the documentation for full details.
Cloning the Database Home
Stop the OMS, database and management agent before cloning the existing Oracle home.
oracle$ $OMS_HOME/bin/emctl stop oms -all ; $AGENT_HOME/bin/emctl stop agent ; $ORACLE_HOME/bin/dbshut $ORACLE_HOME
Create a zip file of the existing database home. Run this step as root (or using sudo) to make sure that you get all the files.
oracle$ sudo zip -r dbhome_1.zip /oracle/oem/product/11.2.0/dbhome_1
Now I will start the original database back up so that OEM continues running while I prepare the cloned Oracle home. I will perform this migration over a few days, as I have time, so I need to keep OEM up and running as much as possible to support and manage my other databases.
oracle$ $ORACLE_HOME/bin/dbstart $ORACLE_HOME ; sleep 10 ; $OMS_HOME/bin/emctl start oms ; sleep 10 ; $AGENT_HOME/bin/emctl start agent
Copy this zip file to the new host.
oracle$ scp dbhome_1.zip oracle@newhost:/oracle/oem
On the new host, extract this zip file to the target directory.
oracle@newhost$ unzip -d / dbhome_1.zip
Remove all “*.ora” files from the extracted $ORACLE_HOME/network/admin directory.
oracle@newhost$ rm /oracle/oem/product/11.2.0/dbhome_1/network/admin/*.ora
Execute clone.pl from $ORACLE_HOME/clone/bin.
oracle@newhost$ export ORACLE_HOME=/oracle/oem/product/11.2.0/dbhome_1 oracle@newhost$ $ORACLE_HOME/perl/bin/perl clone.pl ORACLE_BASE="/oracle/oem" ORACLE_HOME="/oracle/oem/product/11.2.0/dbhome_1" OSDBA_GROUP=dba OSOPER_GROUP=oper -defaultHomeName
Unfortunately this creates an oraInventory directory in the oracle user’s home directory. I prefer to keep oraInventory under ORACLE_BASE, so I moved it and edited the generated files to change the path from /home/oracle/oraInventory to /oracle/oem/oraInventory. Most likely some environment variable, or a previously existing /etc/oraInst.loc would have prevented this optional step.
oracle@newhost$ cp -a ~/oraInventory /oracle/oem oracle@newhost$ cd /oracle/oem/oraInventory oracle@newhost$ perl -pi.bak -e 's#/home/oracle#/oracle/oem#' oraInst.loc orainstRoot.sh
Complete the cloning steps by running the orainstRoot.sh and root.sh scripts.
oracle@newhost$ sudo /oracle/oem/oraInventory/orainstRoot.sh Changing permissions of /oracle/oem/oraInventory. Adding read,write permissions for group. Removing read,write,execute permissions for world. Changing groupname of /oracle/oem/oraInventory to dba. The execution of the script is complete. oracle@newhost$ sudo /oracle/oem/product/11.2.0/dbhome_1/root.sh Check /oracle/oem/product/11.2.0/dbhome_1/install/root_newhost_2013-08-27_13-04-51.log for the output of root script
I do not want to use netca to configure the listener, so I will just copy the $ORACLE_HOME/network/admin/*.ora files back over from the original server to the new server, and edit them accordingly.
oracle$ scp *.ora oracle@newhost:/oracle/oem/product/11.2.0/dbhome_1/network/admin/ oracle@newhost$ cd $ORACLE_HOME/network/admin oracle@newhost$ perl -pi.bak -e 's#oldhost#newhost#' *.ora
This completes the database cloning.
Start Management Repository Database On New Host
At this point you will probably use RMAN to create a backup of your original repository database, then restore that backup onto the new host. Instead, I will cheat a bit, shut down OEM and the database, and ask my sysadmin to move the repository database’s datafile LUN over to the new host and mount it at the same location.
Before moving the LUN, create directories that the database needs for a successful startup. These include the admin/SID/adump directory, and in my case, the /oracle/mirror/SID/cntrl and /oracle/mirror/SID/log directories where I keep the multiplexed copies of my redo logs and controlfiles.
oracle@newhost$ mkdir -p /oracle/oem/admin/emrep/adump oracle@newhost$ mkdir -p /oracle/mirror/emrep/cntrl ; mkdir -p /oracle/mirror/emrep/log
As a sanity check, you should try starting up the listener on the new server and starting the database in NOMOUNT mode before proceeding. This will help catch any issues that may exist in your environment before you start the outage on your original server. Investigate and resolve any issues found before proceeding.
Shutdown the OMS, agent and database on the original server.
oracle$ $OMS_HOME/bin/emctl stop oms -all ; $AGENT_HOME/bin/emctl stop agent ; $ORACLE_HOME/bin/dbshut $ORACLE_HOME
Copy the controlfiles and redo logs from the original server to the new server.
oracle$ scp /oracle/oem/cntrl/control01.ctl oracle@newhost:/oracle/oem/cntrl/control01.ctl oracle$ scp /oracle/mirror/emrep/cntrl/control02.ctl oracle@newhost:/oracle/mirror/emrep/cntrl/control02.ctl oracle$ scp /oracle/oem/log/redo* oracle@newhost:/oracle/oem/log oracle$ scp /oracle/mirror/emrep/log/redo* oracle@newhost:/oracle/mirror/emrep/log
Back on the new server, start up the listener, then the database. I probably should have disabled flashback first.
oracle@newhost$ lsnrctl start LISTENER oracle@newhost$ sqlplus / as sysdba SQL*Plus: Release 188.8.131.52.0 Production on Wed Aug 28 10:09:01 2013 Copyright (c) 1982, 2011, Oracle. All rights reserved. Connected to an idle instance. SQL> startup; ORACLE instance started. Total System Global Area 9620525056 bytes Fixed Size 2236488 bytes Variable Size 6241128376 bytes Database Buffers 3355443200 bytes Redo Buffers 21716992 bytes Database mounted. ORA-38760: This database instance failed to turn on flashback database SQL> select open_mode from v$database; OPEN_MODE -------------------- MOUNTED SQL> alter database flashback off; Database altered. SQL> alter database open; Database altered.
Reconfigure Existing OMS For New Repository Database
Start the OMS and agent on the original server. OMS startup will fail, as you have not yet reconfigured the repository.
oracle$ $OMS_HOME/bin/emctl start oms Oracle Enterprise Manager Cloud Control 12c Release 3 Copyright (c) 1996, 2013 Oracle Corporation. All rights reserved. Starting Oracle Management Server... Starting WebTier... WebTier Successfully Started Oracle Management Server is not functioning because of the following reason: Failed to connect to repository database. OMS will be automatically restarted once it identifies that database and listener are up. Check EM Server log file for details: /oracle/oem/gc_inst/user_projects/domains/GCDomain/servers/EMGC_OMS1/logs/EMGC_OMS1.out oracle$ $AGENT_HOME/bin/emctl start agent
Reconfigure the OMS repository database connection. Provide SYSMAN’s password when prompted.
oracle$ $OMS_HOME/bin/emctl config oms -store_repos_details -repos_conndesc "(DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP)(HOST=newhost)(PORT=1521)))(CONNECT_DATA=(SID=emrep)))" -repos_user sysman Oracle Enterprise Manager Cloud Control 12c Release 3 Copyright (c) 1996, 2013 Oracle Corporation. All rights reserved. Enter Repository User's Password : Successfully updated datasources and stored repository details in Credential Store. If there are multiple OMSs in this environment, run this store_repos_details command on all of them. And finally, restart all the OMSs using 'emctl stop oms -all' and 'emctl start oms'. It is also necessary to restart the BI Publisher Managed Server.
Stop, then restart the OMS.
oracle$ $OMS_HOME/bin/emctl stop oms -all ; sleep 5 ; $OMS_HOME/bin/emctl start oms Oracle Enterprise Manager Cloud Control 12c Release 3 Copyright (c) 1996, 2013 Oracle Corporation. All rights reserved. Stopping WebTier... WebTier Successfully Stopped Stopping Oracle Management Server... Oracle Management Server Successfully Stopped AdminServer Successfully Stopped Oracle Management Server is Down Oracle Enterprise Manager Cloud Control 12c Release 3 Copyright (c) 1996, 2013 Oracle Corporation. All rights reserved. Starting Oracle Management Server... Starting WebTier... WebTier Successfully Started Oracle Management Server Successfully Started Oracle Management Server is Up
Login to OEM and confirm proper operation of the system. I had a lot of alerts for failed backup jobs since my repository database hosts my RMAN catalog. These can wait for now. Also expect your repository target to show as down, since you have not yet updated the monitoring configuration. Reconfigure it now, providing the SYSMAN password when prompted.
oracle$ $OMS_HOME/bin/emctl config emrep -conn_desc "(DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP)(HOST=newhost)(PORT=1521)))(CONNECT_DATA=(SID=emrep)))" Oracle Enterprise Manager Cloud Control 12c Release 3 Copyright (c) 1996, 2013 Oracle Corporation. All rights reserved. Please enter repository password: Enter password : Login successful Target "Management Services and Repository:oracle_emrep" modified successfully Command completed successfully!
At this point you have successfully moved your repository database. Don’t worry about any errors for now, though if you rely on an RMAN catalog and stored scripts for your backups, and these all live in your OEM repository database, you should go through now and update the monitoring configuration for the repository database and listener so that backups of your other databases do not fail. I had to edit the recovery catalog and specify the host, port, and SID manually, since for some reason when I told it to use the repository database it kept trying to use the old hostname. I will fix this after I complete the rest of the migration.
IMPORTANT NOTE: Since you have not yet migrated the repository database target to an agent local to that machine, backups of your repository database may not run. Monitor your archived log directory on this system until you complete the rest of the migration, and manually run backups when necessary.
Installing OMS On A New Host
To install the OMS on a new host, perform a software-only installation from the same EM12c R3 installer that was used to install on the original host. You will need to identify and retrieve all of the plugins that you have installed on the current OMS, as well as any patches that are currently installed on the OMS. You must also make sure to use the same directory layout as on the original OMS.
Identifying Installed Patches
oracle$ $OMS_HOME/OPatch/opatch lsinv -oh $OMS_HOME [...] Interim patches (1) : Patch 13983293 : applied on Thu Jul 11 09:56:16 EDT 2013 Unique Patch ID: 14779750 Created on 25 Apr 2012, 02:18:06 hrs PST8PDT Bugs fixed: 13587457, 13425845, 11822929
This patch gets installed by the EM12c R3 installer, so no need to bother with it any further. If you have other patches installed, go fetch them, and install them after you have completed the plugin installation (see below).
Identifying Installed Plugins
Identify all plugins installed on your system using the query provided in the documentation, run as SYSMAN against your repository database.
SELECT epv.display_name, epv.plugin_id, epv.version, epv.rev_version,decode(su.aru_file, null, 'Media/External', 'https://updates.oracle.com/Orion/Services/download/'||aru_file||'?aru='||aru_id||chr(38)||'patch_file='||aru_file) URL FROM em_plugin_version epv, em_current_deployed_plugin ecp, em_su_entities su WHERE epv.plugin_type NOT IN ('BUILT_IN_TARGET_TYPE', 'INSTALL_HOME') AND ecp.dest_type='2' AND epv.plugin_version_id = ecp.plugin_version_id AND su.entity_id = epv.su_entity_id;
Oracle-provided plugins will show a URL from which you must download the plugin. Third-party plugins will not; you will need to make sure you have the appropriate downloaded plugin install .opar file from when you initially installed it. Gather up all of these plugin files into a single directory on your NEW OMS host, changing the “.zip” filename extension to “.opar” for the Oracle-provided plugins. You need EVERY plugin returned by this query or else your installation will NOT work. I placed mine in /oracle/oem/migration/plugins.
You also need to copy over the three .zip files containing the OEM 12cR3 distribution: V38641-01.zip, V38642-01.zip and V38643-01.zip. Save them into a convenient staging area on the new server (I use /oracle/oem/stage).
Perform Software-Only Installation Of EM12c R3
Go to the staging area on the new server and extract the three .zip files containing the EM12c R3 distribution, then start the installer.
oracle@newhost$ unzip V38641-01.zip ; unzip V38642-01.zip ; unzip V38643-01.zip [...] oracle@newhost$ ./runInstaller
You can follow my previous post about upgrading EM12c R2 to R3 for more information about the installation process, just make sure you run it as a software only install and use the exact same path names as configured on the original OMS. In my case this means a middleware home of /oracle/oem/Middleware12cR3 and an agent base directory of /oracle/oem/agent12c.
While the software installation proceeds, you should run an exportconfig on your current OMS to produce the configuration backup file you will need to use to reconfigure the new one. Enter the SYSMAN password when prompted.
oracle$ $OMS_HOME/bin/emctl exportconfig oms Oracle Enterprise Manager Cloud Control 12c Release 3 Copyright (c) 1996, 2013 Oracle Corporation. All rights reserved. Enter Enterprise Manager Root (SYSMAN) Password : ExportConfig started... Machine is Admin Server host. Performing Admin Server backup... Exporting emoms properties... Exporting secure properties... Export has determined that the OMS is not fronted by an SLB. The local hostname was NOT exported. The exported data can be imported on any host but resecure of all agents will be required. Please see the EM Advanced Configuration Guide for more details. Exporting configuration for pluggable modules... Preparing archive file... Backup has been written to file: /oracle/oem/gc_inst/em/EMGC_OMS1/sysman/backup/opf_ADMIN_20130828_120424.bka The export file contains sensitive data. You must keep it secure. ExportConfig completed successfully!
Copy that backup file to the new server.
oracle$ scp /oracle/oem/gc_inst/em/EMGC_OMS1/sysman/backup/opf_ADMIN_20130828_120424.bka oracle@newhost:/oracle/oem
Once the software-only install finishes, it will prompt you to run allroot.sh. Do so.
oracle@newhost$ sudo /oracle/oem/Middleware12cR3/oms/allroot.sh Starting to execute allroot.sh ......... Starting to execute /oracle/oem/Middleware12cR3/oms/root.sh ...... Running Oracle 11g root.sh script... The following environment variables are set as: ORACLE_OWNER= oracle ORACLE_HOME= /oracle/oem/Middleware12cR3/oms Enter the full pathname of the local bin directory: [/usr/local/bin]: The file "dbhome" already exists in /usr/local/bin. Overwrite it? (y/n) [n]: The file "oraenv" already exists in /usr/local/bin. Overwrite it? (y/n) [n]: The file "coraenv" already exists in /usr/local/bin. Overwrite it? (y/n) [n]: Entries will be added to the /etc/oratab file as needed by Database Configuration Assistant when a database is created Finished running generic part of root.sh script. Now product-specific root actions will be performed. /etc exist Creating /etc/oragchomelist file... /oracle/oem/Middleware12cR3/oms Finished execution of /oracle/oem/Middleware12cR3/oms/root.sh ...... Starting to execute /oracle/oem/agent12c/core/184.108.40.206.0/root.sh ...... Finished product-specific root actions. /etc exist /oracle/oem/agent12c/core/220.127.116.11.0 Finished execution of /oracle/oem/agent12c/core/18.104.22.168.0/root.sh ......
After running allroot.sh, you need to run the PluginInstall.sh script with the path where you saved the .opar files. Make sure you select every plugin listed when you ran the query to retrieve the plugin list earlier, then hit install.
oracle@newhost$ /oracle/oem/Middleware12cR3/oms/sysman/install/PluginInstall.sh -pluginLocation /oracle/oem/migration/plugins
Prepare the Software Library
Go to the original server, and copy the contents of the software library to the new server.
oracle$ scp -r /oracle/oem/software_library/ oracle@newhost:/oracle/oem
Recreate the OMS with OMSCA
Shut everything down on your old server.
oracle$ $OMS_HOME/bin/emctl stop oms -all ; sleep 5 ; $AGENT_HOME/bin/emctl stop agent
Run OMSCA using the exportconfig backup file you generated earlier. Enter the administration server, node manager, repository database user and agent registration passwords when prompted.
oracle@newhost$ $OMS_HOME/bin/omsca recover -as -ms -nostart -backup_file /oracle/oem/opf_ADMIN_20130828_120424.bka Oracle Enterprise Manager Cloud Control 12c Release 22.214.171.124.0 Copyright (c) 1996, 2013, Oracle. All rights reserved. OS check passed. OMS version check passed. Performing Admin Server Recovery... Retrieved Admin Server template. Source Instance Host name where configuration is exported : [deleted] Populated install params from backup... Enter Administration Server user password: Confirm Password: Enter Node Manager Password: Confirm Password: Enter Repository database user password: Enter Agent Registration password: Confirm Password: Doing pre requisite checks ...... Pre requisite checks completed successfully Checking Plugin software bits Proceed to recovery Setting up domain from template... Setup EM infrastructure succeeded! Admin Server recovered from backup. Now performing cleanup of OMS EMGC_OMS1... Now launching DeleteOMS... OMS Deleted successfully Delete finished successfully Now launching AddOMS... Infrastructure setup of EM completed successfully. Doing pre deployment operations ...... Pre deployment of EM completed successfully. Deploying EM ...... Deployment of EM completed successfully. Configuring webtier ...... Configuring webTier completed successfully. Importing OMS configuration from recovery file... If you have software library configured please make sure it is functional and accessible from this OMS by visiting: Setup->Provisioning and Patching->Software Library Securing OMS ...... Adapter already exists: emgc_USER Adapter already exists: emgc_GROUP Post "Deploy and Repos Setup" operations completed successfully. Performing Post deploy operations .... Total 0 errors, 78 warnings. 0 entities imported. pluginID:oracle.sysman.core Done with csg import pluginID:oracle.sysman.core Done with csg import No logging has been configured and default agent logging support is unavailable. Post deploy operations completed successfully. EM configuration completed successfully. EM URL is:https://newhost:7803/em Add OMS finished successfully Recovery of server EMGC_OMS1 completed successfully OMSCA Recover completed successfully
Start the OMS on the new server.
oracle@newhost$ $OMS_HOME/bin/emctl start oms
Configure the central agent on the new server, then run the root.sh script.
oracle@newhost$ /oracle/oem/agent12c/core/126.96.36.199.0/sysman/install/agentDeploy.sh AGENT_BASE_DIR=/oracle/oem/agent12c AGENT_INSTANCE_HOME=/oracle/oem/agent12c/agent_inst AGENT_PORT=3872 -configOnly OMS_HOST=newhost EM_UPLOAD_PORT=4902 AGENT_REGISTRATION_PASSWORD=password [...] oracle@newhost$ sudo /oracle/oem/agent12c/core/188.8.131.52.0/root.sh
Relocate the oracle_emrep target to the new OMS host.
oracle@newhost$ $OMS_HOME/bin/emcli login -username=sysman Enter password : Login successful oracle@newhost$ $OMS_HOME/bin/emcli sync Synchronized successfully oracle@newhost$ $OMS_HOME/bin/emctl config emrep -agent newhost:3872 Oracle Enterprise Manager Cloud Control 12c Release 3 Copyright (c) 1996, 2013 Oracle Corporation. All rights reserved. Please enter repository password: Enter password : Login successful Moved all targets from oldhost:3872 to newhost:3872 Command completed successfully! Enter password : Login successful Moved all targets from oldhost:3872 to newhost:3872 Command completed successfully!
Step through each of your existing agents to re-secure them against the new OMS. Provide the OMS HTTP port (not HTTPS) in this command, and enter the agent registration password when prompted.
$ $AGENT_INSTANCE_DIR/bin/emctl secure agent -emdWalletSrcUrl "http://newhost:4890/em" Oracle Enterprise Manager Cloud Control 12c Release 3 Copyright (c) 1996, 2013 Oracle Corporation. All rights reserved. Agent successfully stopped... Done. Securing agent... Started. Enter Agent Registration Password : Agent successfully restarted... Done. EMD gensudoprops completed successfully Securing agent... Successful.
Start the agent on the old OMS server. You should not need to do this, but I could not update the WebLogic Domain monitoring configuration without doing so first. Also re-secure this agent to point to the new OMS.
oracle$ $AGENT_HOME/bin/emctl start agent oracle$ $AGENT_INSTANCE_DIR/bin/emctl secure agent -emdWalletSrcUrl "http://newhost:4890/em"
Login to the OEM GUI running on the new server and navigate to the WebLogic Domain target for the Cloud Control domain. In the Target Setup -> Monitoring Credentials section, update the Administration server host value to the new server name, then hit OK. Then execute a Refresh WebLogic Domain, selecting Add/Update Targets, to move all WebLogic targets to the new central agent.
I use third-party plugins to monitor VMWare targets, NetApp storage and MySQL servers. I had many of them set up to run from the OMS agent (except for the VMWare ones, since Blue Medora helpfully advised not to use the OMS agent for this — great advice). I now need to relocate each of these targets to the new central agent using emcli. You won’t need to do this step unless you also have things set up this way. If I had to do this again, I would not use the OMS agent for these targets, since I would not need to change anything if I just had these on some other agent.
oracle@newhost$ ./emcli relocate_targets -src_agent=oldhost:3872 -dest_agent=newhost:3872 -copy_from_src -target_name=nameoftarget -target_type=typeoftarget
Final Cleanup Steps
By now you have completed the bulk of the work necessary to migrate your EM12c stack to a new server. Only a few steps remain. If you use any utility scripts on the old server, go ahead and copy those over now. I have scripts to automate starting/stopping the OMS and agent, so I’ve copied those over. Also make sure the oracle user on the new server has all the environment variables set up in their shell initialization files.
oracle$ scp ~/bin/CCstart ~/bin/CCstop oracle@newhost:bin/
The GCDomain Oracle WebLogic Domain target did not get moved to my new agent. If this happened to you, go to the target home page and select the Modify Agents menu item. Click Continue, then find GCDomain in the list, scroll to the right, and assign the new OMS server’s agent as the monitoring agent for this target, then click the Modify Agents button.
Reinstall BI Publisher
Since I had BI Publisher installed on the old server, I need to install it again on the new one. Retrieve the 184.108.40.206.0 BI Publisher installation files used previously, and copy them to your staging area. Run the “runInstaller” program from bishiphome/Disk1, and perform a software-only installation with the middleware home set to your EM12c installation middleware home, and leave the Oracle home as Oracle_BI1.
Instead of running the configureBIP script as you normally would to integrate BI Publisher with EM12c, just go to the WebLogic administration console after the software-only install completes, and navigate to the BIP server configuration page. Lock the configuration for editing, and edit the configuration to change the listen address to reference the new server’s hostname and change the machine to the machine name where the admin server runs (in my case it showed up as EMGC_MACHINE2). Save and activate the changes, then start the BIP server.
After the server has started, return to the WebLogic Domain page and re-run the Refresh WebLogic Domain step, again with Add/Update targets, to move BIP to your new OMS agent.
I actually had to do the Refresh WebLogic Domain step here twice. I may have simply not waited long enough after starting BIP before I ran it, but I do not know for sure.
Update EM Console Service
I have only one target showing down at this point, the EM Console Service. Go to the target, and click on the Monitoring Configuration tab. Click on Service Tests and Beacons. Select the EM Console Service Test, and click the Edit button. Make sure you have the “Access Login page” step selected, and click Edit. Change the URL to reflect your new OEM server, and save the changes.
Remove Previous OMS Server From OEM
Stop the agent on your original OMS server.
oracle$ $AGENT_HOME/bin/emctl stop agent
Remove the host target where your original OMS ran. Then remove the agent target.
One Last Bounce
Finally, bounce the whole thing one last time, then start it back up. All green.
I would prefer a simpler process to migrate the EM12c stack to a new server, but this works. If you find yourself in a similar position to mine, I hope this helps you. I’ve spent a lot of time working in EM12c so I feel capable to diagnose and resolve issues encountered during the process, but if you run into problems do not hesitate to contact Oracle Support and file a service requests. If you want your system to stay supportable, stick with the experts and just use blogs as a guide to get started. Good luck.