OMS version not checked yet while emctl upload agent

After OEM managed host was bounced, the agent status shows 'DOWN' in OEM. It happened because old version agent which pointed to old OMS server was started.

Find out if OEM agent is running on target,

$ ps -ef | grep emagent
  oracle 63111344 41484628   0 14:10:15  pts/0  0:00 grep emagent
  oracle  7143666        1   0 13:55:39  pts/4  0:00 /u01/app/oracle/product/12.1.0/agent/core/12.1.0.4.0/perl/bin/perl /u01/app/oracle/product/12.1.0/agent/core/12.1.0.4.0/bin/emwd.pl agent /u01/app/oracle/product/12.1.0/agent/agent_inst/sysman/log/emagent.nohup
  oracle 26280338  7143666   0 13:55:51  pts/4  0:06 /u01/app/oracle/product/12.1.0/agent/core/12.1.0.4.0/jdk/bin/java -Xmx160M -server -Djava.security.egd=file:///dev/./urandom -Dsun.lang.ClassLoader.allowArraySyntax=true -Xgcpolicy:gencon -Dwatchdog.pid=7143666 -cp /u01/app/oracle/product/12.1.0/agent/core/12.1.0.4.0/jdbc/lib/ojdbc5.jar:/u01/app/oracle/product/12.1.0/agent/core/12.1.0.4.0/ucp/lib/ucp.jar:/u01/app/oracle/product/12.1.0/agent/core/12.1.0.4.0/modules/oracle.http_client_11.1.1.jar:/u01/app/oracle/product/12.1.0/agent/core/12.1.0.4.0/lib/xmlparserv2.jar:/u01/app/oracle/product/12.1.0/agent/core/12.1.0.4.0/lib/jsch.jar:/u01/app/oracle/product/12.1.0/agent/core/12.1.0.4.0/lib/optic.jar:/u01/app/oracle/product/12.1.0/agent/core/12.1.0.4.0/modules/oracle.dms_11.1.1/dms.jar:/u01/app/oracle/product/12.1.0/agent/core/12.1.0.4.0/modules/oracle.odl_11.1.1/ojdl.jar:/u01/app/oracle/product/12.1.0/agent/core/12.1.0.4.0/modules/oracle.odl_11.1.1/ojdl2.jar:/u01/app/oracle/product/12.1.0/agent/core/12.1.0.4.0/sysman/jlib/log4j-core.jar:/u01/app/oracle/product/12.1.0/agent/core/12.1.0.4.0/jlib/gcagent_core.jar:/u01/app/oracle/product/12.1.0/agent/core/12.1.0.4.0/sysman/jlib/emagentSDK-intg.jar:/u01/app/oracle/product/12.1.0/agent/core/12.1.0.4.0/sysman/jlib/emagentSDK.jar oracle.sysman.gcagent.tmmain.TMMain

There is an instance of OEM agent running from Oracle Home '/u01/app/oracle/product/12.1.0/agent/core/12.1.0.4.0'. Test the communication between managed host and the Management Service,

$ /u01/app/oracle/product/12.1.0/agent/core/12.1.0.4.0/bin/emctl upload agent
Oracle Enterprise Manager Cloud Control 12c Release 4 
Copyright (c) 1996, 2014 Oracle Corporation.  All rights reserved.
---------------------------------------------------------------
EMD upload error:full upload has failed: uploadXMLFiles skipped :: OMS version not checked yet. If this issue persists check trace files for ping to OMS related errors. (OMS_DOWN)

$ /u01/app/oracle/product/12.1.0/agent/core/12.1.0.4.0/bin/emctl pingOMS
Oracle Enterprise Manager Cloud Control 12c Release 4 
Copyright (c) 1996, 2014 Oracle Corporation.  All rights reserved.
---------------------------------------------------------------
EMD pingOMS error: Failure connecting to https://oem.dbaplus.ca:1159/empbs/upload , err Connection refused

Command 'emctl upload agent' returned error 'OMS version not checked yet', and 'emctl pingOMS' is complaining that OMS server cannot be connected. However, current OMS server is oms.dbaplus.ca and not oem.dbaplus.ca which is retired. Apparently, bouncing host automatically started an old (obsolete) agent which worked with old OMS server.

Let's fix it,

$ cat /etc/oragchomelist

/u01/app/oracle/product/12.1.0/agent/core/12.1.0.4.0:/u01/app/oracle/product/12.1.0/agent/agent_inst

/u01/app/oracle/product/em/agent/agent_13.2.0.0.0:/u01/app/oracle/product/em/agent/agent_inst

The first entry in file /etc/oragchomelist makes OS start old agent (version 12.1.0.4), remove it from /etc/oragchomelist and restart host. After host is up, check agent status,

$ cat /etc/oragchomelist
/u01/app/oracle/product/em/agent/agent_13.2.0.0.0:/u01/app/oracle/product/em/agent/agent_inst

$ ps -ef | grep emagent
  oracle 57082074 41484628   0 16:21:18  pts/0  0:00 grep emagent
  oracle 63766548        1   0 15:00:53  pts/0  0:00 /u01/app/oracle/product/em/agent/agent_13.2.0.0.0/perl/bin/perl /u01/app/oracle/product/em/agent/agent_13.2.0.0.0/bin/emwd.pl agent /u01/app/oracle/product/em/agent/agent_inst/sysman/log/emagent.nohup
  oracle 29950448 63766548   0 15:01:00  pts/0  1:20 /u01/app/oracle/product/em/agent/agent_13.2.0.0.0/oracle_common/jdk/bin/java -Xmx183M -server -Djava.security.egd=file:///dev/./urandom -Dsun.lang.ClassLoader.allowArraySyntax=true -Xgcpolicy:gencon -Dwatchdog.pid=63766548 -cp /u01/app/oracle/product/em/agent/agent_13.2.0.0.0/jdbc/lib/ojdbc7.jar:/u01/app/oracle/product/em/agent/agent_13.2.0.0.0/ucp/lib/ucp.jar:/u01/app/oracle/product/em/agent/agent_13.2.0.0.0/oracle_common/modules/jsch-0.1.53.jar:/u01/app/oracle/product/em/agent/agent_13.2.0.0.0/oracle_common/modules/com.oracle.http_client.http_client_12.1.3.jar:/u01/app/oracle/product/em/agent/agent_13.2.0.0.0/oracle_common/modules/oracle.xdk_12.1.3/xmlparserv2.jar:/u01/app/oracle/product/em/agent/agent_13.2.0.0.0/oracle_common/modules/oracle.dms_12.1.3/dms.jar:/u01/app/oracle/product/em/agent/agent_13.2.0.0.0/oracle_common/modules/oracle.odl_12.1.3/ojdl.jar:/u01/app/oracle/product/em/agent/agent_13.2.0.0.0/oracle_common/modules/oracle.odl_12.1.3/ojdl2.jar:/u01/app/oracle/product/em/agent/agent_13.2.0.0.0/lib/optic.jar:/u01/app/oracle/product/em/agent/agent_13.2.0.0.0/sysman/jlib/log4j-core.jar:/u01/app/oracle/product/em/agent/agent_13.2.0.0.0/jlib/gcagent_core.jar:/u01/app/oracle/product/em/agent/agent_13.2.0.0.0/sysman/jlib/emagentSDK-intg.jar:/u01/app/oracle/product/em/agent/agent_13.2.0.0.0/sysman/jlib/emagentSDK.jar oracle.sysman.gcagent.tmmain.TMMain

$ /u01/app/oracle/product/em/agent/agent_13.2.0.0.0/bin/emctl upload agent
Oracle Enterprise Manager Cloud Control 13c Release 2
Copyright (c) 1996, 2016 Oracle Corporation.  All rights reserved.
---------------------------------------------------------------
EMD upload completed successfully

$ /u01/app/oracle/product/em/agent/agent _13.2.0.0.0/bin/emctl status agent
Oracle Enterprise Manager Cloud Control 13c Release 2 
Copyright (c) 1996, 2016 Oracle Corporation.  All rights reserved.
---------------------------------------------------------------
Agent Version          : 13.2.0.0.0
OMS Version            : 13.2.0.0.0
Protocol Version       : 12.1.0.1.0
Agent Home             : /u01/app/oracle/product/em/agent/agent_inst
Agent Log Directory    : /u01/app/oracle/product/em/agent/agent_inst/sysman/log
Agent Binaries         : /u01/app/oracle/product/em/agent/agent_13.2.0.0.0
Core JAR Location      : /u01/app/oracle/product/em/agent/agent_13.2.0.0.0/jlib
Agent Process ID       : 11665618
Parent Process ID      : 13238612
Agent URL              : https://host01.dbaplus.ca:3872/emd/main/
Local Agent URL in NAT : https://host01.dbaplus.ca:3872/emd/main/
Repository URL         : https://oms.dbaplus.ca:4903/empbs/upload
Started at             : 2017-01-26 14:25:33
Started by user        : oracle
Operating System       : AIX version 7.1 (ppc64)
Number of Targets      : 23
Last Reload            : (none)
Last successful upload                       : 2017-01-26 14:27:22
Last attempted upload                        : 2017-01-26 14:27:22
Total Megabytes of XML files uploaded so far : 0.62
Number of XML files pending upload           : 734
Size of XML files pending upload(MB)         : 0.31
Available disk space on upload filesystem    : 59.62%
Collection Status                            : Collections enabled
Heartbeat Status                             : Ok
Last attempted heartbeat to OMS              : 2017-01-26 14:26:26
Last successful heartbeat to OMS             : 2017-01-26 14:26:26
Next scheduled heartbeat to OMS              : 2017-01-26 14:27:28

---------------------------------------------------------------
Agent is Running and Ready

Agent is running on managed host, and it also shows 'UP' in OEM.