Creating an alarm without description, and later on updating threshold / meter won't update (change) the output default description. This can be really confusing for end users.
Sample
-------------
+---------------------------+----------------------------------------------------------------------+
| Property | Value |
+---------------------------+----------------------------------------------------------------------+
| alarm_actions | [u'http://localhost:12000/'] |
| alarm_id | 7c1324d2-a96b-4f6f-af52-c05ea33fd866 |
| comparison_operator | lt |
| description | Alarm when network.outgoing.bytes is lt a avg of 33.0 over 5 seconds |
| enabled | True |
| evaluation_periods | 1 |
| exclude_outliers | False |
| insufficient_data_actions | [u'http://localhost:12000/'] |
| meter_name | new |
| name | bytes |
| ok_actions | [u'http://localhost:12000/'] |
| period | 100 |
| project_id | c8d29398c19846b2b7b7175a8acf73c9 |
| query | |
| repeat_actions | True |
| state | insufficient data |
| statistic | avg |
| threshold | 33.0 |
| type | threshold |
| user_id | 79816b624879417fa12dd7ecdc395a0e |
+---------------------------+----------------------------------------------------------------------+
ubuntu@ubuntu-SVT13125CLS:/opt/stack/ceilometer/ceilometer/api$ ceilometer alarm-threshold-update -a 7c1324d2-a96b-4f6f-af52-c05ea33fd866 -m new --threshold 500
+---------------------------+----------------------------------------------------------------------+
| Property | Value |
+---------------------------+----------------------------------------------------------------------+
| alarm_actions | [u'http://localhost:12000/'] |
| alarm_id | 7c1324d2-a96b-4f6f-af52-c05ea33fd866 |
| comparison_operator | lt |
| description | Alarm when network.outgoing.bytes is lt a avg of 33.0 over 5 seconds |
| enabled | True |
| evaluation_periods | 1 |
| exclude_outliers | False |
| insufficient_data_actions | [u'http://localhost:12000/'] |
| meter_name | new |
| name | bytes |
| ok_actions | [u'http://localhost:12000/'] |
| period | 100 |
| project_id | c8d29398c19846b2b7b7175a8acf73c9 |
| query | |
| repeat_actions | True |
| state | insufficient data |
| statistic | avg |
| threshold | 500.0 |
| type | threshold |
| user_id | 79816b624879417fa12dd7ecdc395a0e |
+---------------------------+----------------------------------------------------------------------+
so if we call rest api, we need to provide the description explicitly, otherwise it will be set to default generated description, I think this problem exists in python- ceilometerclien t side