Ambari: MySQL status failed but service is runnning

Products

• Services Suite

Issue/Introduction

Symptoms:

MySQL server shows as stopped in Ambari interface. Even after trying to start it, it blinks green for a while, and then shows stopped again. The following error is present in ambari.log

INFO 2015-04-30 10:44:44,137 PythonExecutor.py:118 - Result: {'structuredOut': {}, 'stdout': '2015-04-30 10:44:44,045 - Execute[\'service mysqld status | grep running\'] 
 {} 
 2015-04-30 10:44:44,107 - Error while executing command \'status\': 
 Traceback (most recent call last): 
 File "/usr/lib/python2.6/site-packages/resource_management/libraries/script/script.py", 
 line 123, in execute 
 method(env) 
 File "/var/lib/ambari-agent/cache/stacks/PHD/2.0.6/services/HIVE/package/scripts/mysql_server.py", line 67, in status 
 mysql_service(daemon_name=status_params.daemon_name, action = \'status\') 
 File "/var/lib/ambari-agent/cache/stacks/PHD/2.0.6/services/HIVE/package/scripts/mysql_service.py", line 29, in mysql_service 
 Execute(status_cmd) 
 File "/usr/lib/python2.6/site-packages/resource_management/core/base.py", line 148, in __init__ 
 self.env.run() 
 File "/usr/lib/python2.6/site-packages/resource_management/core/environment.py", line 149, in run 
 self.run_action(resource, action) 
 File "/usr/lib/python2.6/site-packages/resource_management/core/environment.py", line 115, in run_action 
 provider_action() 
 File "/usr/lib/python2.6/site-packages/resource_management/core/providers/system.py", line 241, in action_run 
 raise ex 
 Fail: Execution of \'service mysqld status | grep running\' returned 1.', 'stderr': '2015-04-30 10:44:44,107 - Error while executing command \'status\': 
 Traceback (most recent call last): 
 File "/usr/lib/python2.6/site-packages/resource_management/libraries/script/script.py", line 123, in execute 
 method(env) 
 File "/var/lib/ambari-agent/cache/stacks/PHD/2.0.6/services/HIVE/package/scripts/mysql_server.py", line 67, in status 
 mysql_service(daemon_name=status_params.daemon_name, action = \'status\') 
 File "/var/lib/ambari-agent/cache/stacks/PHD/2.0.6/services/HIVE/package/scripts/mysql_service.py", line 29, in mysql_service 
 Execute(status_cmd) 
 File "/usr/lib/python2.6/site-packages/resource_management/core/base.py", line 148, in __init__ 
 self.env.run() 
 File "/usr/lib/python2.6/site-packages/resource_management/core/environment.py", line 149, in run 
 self.run_action(resource, action) 
 File "/usr/lib/python2.6/site-packages/resource_management/core/environment.py", line 115, in run_action 
 provider_action() 
 File "/usr/lib/python2.6/site-packages/resource_management/core/providers/system.py", 
 line 241, in action_run 
 raise ex 
 Fail: Execution of \'service mysqld status | grep running\' returned 1.', 'exitcode': 1} 
 

Environment

Cause

Ambari does some checks based on command outputs. The checks assume that language is in English; so those checks will fail for locales that change output messages (e.g. German, Italian, Spanish, etc.)

Resolution

As a workaround, we have to modify manually the following file:

/var/lib/ambari-server/resources/stacks/PHD/2.0.6/services/HIVE/package/scripts/mysql_service.py

And change the line 25 in the following way:

- status_cmd = format('service {daemon_name} status | grep running')
+ status_cmd = format("pgrep -l '^{daemon_name}$'")