Oracle Golden Gate Error: OGG-01221 Connect failed to 111.222.333.444:7819 error 111:Connection refused.

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General
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After starting Golden Gate processes, Extract processes having this error:
Error in Golden gate after starting up golden gate extract processes

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Solution A
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application user is running the GG processes and lacks the permission to update ggserr.log file.

On both server A and server B:

ls -l ggserr.log
-rw-r-----.  1 root   root  8305860 Aug 31 20:30 ggserr.log

as root

chmod 666 ggserr.log

restart the GG processes

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Solution B
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Remove the line in red, and restart GG processes.
This should be done on site A and on site B.

# Do not remove the following line, or various programs
# that require network functionality will fail.
::1               localhost6.localdomain6 localhost6
127.0.0.1         localhost.localdomain   localhost
111.222.333.445   XXXDB00001              XXX7DB00001.mydomain.com
111.222.333.445   XXXDB00002              XXXDB00002.mydomain.com
111.222.333.447   xxx-2-ora-01            xxx-2-ora-01.mydomain.com

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Appendix
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Rollover the ggserr.log keeping existing permissions:

cp -pnv ggserr.log ggserr.log_20200831

-p : preserve permissions

-v : verbose, print informative messages

-n : no file overwrite

cat /dev/null > ggserr.log

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Reference
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https://dbamind.wordpress.com/2015/03/16/error-ogg-01224-1connection-refused/

::1 localhost6.localdomain6 localhost6
It is IPV6 address for localhost
(IPV4 would be simple 127.0.0.1 localhost)