Startup of HTTP LISTENER failure (00716)

$ emctl start dbconsole
Oracle Enterprise Manager 11g Database Control Release 11.2.0.2.0
Copyright (c) 1996, 2010 Oracle Corporation.  All rights reserved.
https://DBA01:5501/em/console/aboutApplication
Starting Oracle Enterprise Manager 11g Database Control ............................................................................................. failed.
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Logs are generated in directory /d02/app/oracle/product/11.2.0/dbhome/dba01_DBT/sysman/log
$ cd /d02/app/oracle/product/11.2.0/dbhome/dba01_DBT/sysman/log
$ cat emagent.log
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2019-07-01 10:57:03,667 Thread-1 Starting Agent 10.2.0.4.3 from /d02/app/oracle/product/11.2.0/dbhome (00701)
2019-07-01 10:57:03,668 Thread-1 : Startup of HTTP LISTENER failure (00716)

$ ps -ef|grep -i em
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 oracle  5505504        1   0   Jun 07      - 94:05 /d02/app/oracle/product/11.2.0/dbhome/bin/emagent

$ kill -9 5505504

$ ps -ef|grep -i em
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oracle  8847674  7274908   0 11:09:43  pts/0  0:00 grep -i em

$ emctl start dbconsole
Oracle Enterprise Manager 11g Database Control Release 11.2.0.2.0
Copyright (c) 1996, 2010 Oracle Corporation.  All rights reserved.
https://DBA01:5501/em/console/aboutApplication
Starting Oracle Enterprise Manager 11g Database Control ...... started.
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Logs are generated in directory /d02/app/oracle/product/11.2.0/dbhome/dba01_DBT/sysman/log
$