PMM3 + mongodb. 2 questions - about mongodb_mongolog_agent and Query Analytics panel

Percona Monitoring and Management (PMM) PMM 3.x
1

Firts of all, thx four your beautifull app guys! It really helps !

So we use pmm server 3.3.0 with pmm-client-3.4.1 for gathering stats from mongodb nodes.
And found some problems.

1. After restart mongod service , mongodb_mongolog_agent comes to Unspecified state and stops gather Slow queries.

# pmm-admin list

Service type        Service name          Address and port        Service ID
MongoDB             mg-db-p03        127.0.0.1:27017         b92361fa-3b03-405d-ad75-6462774fe449

Agent type                    Status             Metrics Mode        Agent ID                                    Service ID                                  Port
pmm_agent                     Connected                              49d1af6b-395b-4749-89cf-46de0be16d58                                                    0
node_exporter                 Running            push                e5afac4e-2719-4817-ae02-fd75ce40f067                                                    42002
mongodb_exporter              Running            push                d35a7a52-b7fc-489e-8b04-0e693a5dc2c3        b92361fa-3b03-405d-ad75-6462774fe449        42001
mongodb_mongolog_agent        Unspecified                            3ed4f165-f614-4fae-a11d-714c00d2de37        b92361fa-3b03-405d-ad75-6462774fe449        0
vmagent                       Running            push                8f78d78c-8dd6-4ef5-8298-c02aaee75820                                                    42000

Restart the agent helps to relosolve this problem, It would be nice if restarting mongo didn’t break the agent.

2. explain plans on the Query Analytics panel isn’t showed. We use gather from logfile. Look on attached screen

image
image581×770 42.9 KB

2

Hi, glad you are enjoying PMM!

  1. Do you use any logrotate config that might be interfering? reopen is required as per the doc MongoDB - Percona Monitoring and Management
  2. Unfortunately mongo is quite strict with explain and requires perms to actually execute the operation in order to explain it. You can try giving pmm user the full backup management privileges as per MongoDB - Percona Monitoring and Management and it should work