Problem:
[XXXPRO1]/oracle/product/11.1.0/agent11g/bin $ ./emctl upload agent
Oracle Enterprise Manager 11g Release 1 Grid Control 11.1.0.1.0
Copyright (c) 1996, 2010 Oracle Corporation. All rights reserved.
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EMD upload error: uploadXMLFiles skipped :: OMS version not checked yet. If this issue persists check trace files for ping to OMS related errors.
Solution:
When you get this warning you should also check "emctl status agent" output.
[XXXPRO1]/oracle/product/11.1.0/agent11g/bin $ ./emctl status agent
Oracle Enterprise Manager 11g Release 1 Grid Control 11.1.0.1.0
Copyright (c) 1996, 2010 Oracle Corporation. All rights reserved.
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Agent Version : 11.1.0.1.0
OMS Version : 11.1.0.1.0
Protocol Version : 11.1.0.0.0
Agent Home : /oracle/product/11.1.0/agent11g/hostxxx01
Agent binaries : /oracle/product/11.1.0/agent11g
Agent Process ID : 8091
Parent Process ID : 8080
Agent URL : https://hostxxx01:1830/emd/main
Repository URL : https://hostemgrid01:1159/em/upload
Started at : 2012-06-21 11:13:55
Started by user : oracle
Last Reload : 2012-06-21 11:13:55
Last successful upload : (none)
Last attempted upload : (none)
Total Megabytes of XML files uploaded so far : 0.00
Number of XML files pending upload : 273
Size of XML files pending upload(MB) : 52.42
Available disk space on upload filesystem : 47.97%
Collection Status : Disabled by Upload Manager
Last attempted heartbeat to OMS : 2012-06-21 11:26:12
Last successful heartbeat to OMS : unknown
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Agent is Running and Ready