Retained messages
Inspecting the retained message store
To list the retained messages simply invoke
vmq-admin retain show
:$ vmq-admin retain show
+------------------+----------------+
| payload | topic |
+------------------+----------------+
| a-third-message | a/third/topic |
|some-other-message|some/other/topic|
| a-message | some/topic |
| a-message | another/topic |
+------------------+----------------+
Note, by default a maximum of 100 results are returned. This is a mechanism to protect the from overload as there can be millions of retained messages. Use
--limit=<RowLimit>
to override the default value.Besides listing the retained messages it is also possible to filter them:
$ vmq-admin retain show --payload --topic=some/topic
+---------+
| payload |
+---------+
|a-message|
+---------+
In the above example we list only the payload for the topic
some/topic
.Another example where all topics are list with retained messages with a specific payload:
$ vmq-admin retain show --payload a-message --topic
+-------------+
| topic |
+-------------+
| some/topic |
|another/topic|
+-------------+
See the full set of options and documentation by invoking
vmq-admin retain show --help
:$ sudo vmq-admin retain --help
Usage: vmq-admin retain show
Show and filter MQTT retained messages.
Default options:
--payload --topic
Options
--limit=<NumberOfResults>
Limit the number of results returned. Defaults is 100.
--payload
--topic
--mountpoint