Note: All commands are written for juju >= v3.1
If you’re using juju 2.9, check the juju 3.0 Release Notes.
Enable tracing
This guide contains the steps to enable tracing with Grafana Tempo for your MySQL Router application.
To summarize:
- Deploy the Tempo charm in a COS K8s environment
- Integrate it with the COS charms
- Offer interfaces for cross-model integrations
- View MySQLRouter traces on Grafana
Warning: This is feature is in development. It is not recommended for production environments.
This feature is available for Charmed MySQL Router revision 208+ only.
Prerequisites
Enabling tracing with Tempo requires that you:
- Have deployed a Charmed MySQL application
- Have deployed a Charmed MySQL Router application in the same model as the Charmed MySQL application
- Have deployed a ‘cos-lite’ bundle from the
latest/edgetrack in a Kubernetes environment
Deploy Tempo
First, switch to the Kubernetes controller where the COS model is deployed:
juju switch <k8s_controller_name>:<cos_model_name>
Then, deploy the tempo-k8s charm:
juju deploy -n 1 tempo-k8s --channel latest/edge
Integrate with the COS charms
Integrate tempo-k8s with the COS charms as follows:
juju integrate tempo-k8s:grafana-dashboard grafana:grafana-dashboard
juju integrate tempo-k8s:grafana-source grafana:grafana-source
juju integrate tempo-k8s:ingress traefik:traefik-route
juju integrate tempo-k8s:metrics-endpoint prometheus:metrics-endpoint
juju integrate tempo-k8s:logging loki:logging
If you would like to instrument traces from the COS charms as well, create the following integrations:
juju integrate tempo-k8s:tracing alertmanager:tracing
juju integrate tempo-k8s:tracing catalogue:tracing
juju integrate tempo-k8s:tracing grafana:tracing
juju integrate tempo-k8s:tracing loki:tracing
juju integrate tempo-k8s:tracing prometheus:tracing
juju integrate tempo-k8s:tracing traefik:tracing
Offer interfaces
Next, offer interfaces for cross-model integrations from the model where Charmed MySQL Router is deployed.
To offer the Tempo integration, run
juju offer tempo-k8s:tracing
Then, switch to the Charmed MySQL Router model, find the offers, and integrate (relate) with them:
juju switch <machine_controller_name>:<mysql_router_model_name>
juju find-offers <k8s_controller_name>:
Do not miss the “
:” in the command above.
Below is a sample output where k8s is the K8s controller name and cos is the model where cos-lite and tempo-k8s are deployed:
Store URL Access Interfaces
k8s admin/cos.tempo-k8s admin tracing:tracing
Next, consume this offer so that it is reachable from the current model:
juju consume k8s:admin/cos.tempo-k8s
Relate Charmed MySQL Router with the above consumed interface:
juju integrate mysql-router:tracing tempo-k8s:tracing
Wait until the model settles. The following is an example of the juju status --relations on the Charmed MySQL Router model:
Model Controller Cloud/Region Version SLA Timestamp
database lxd localhost/localhost 3.4.3 unsupported 12:48:46Z
SAAS Status Store URL
tempo-k8s active uk8s admin/cos.tempo-k8s
App Version Status Scale Charm Channel Rev Exposed Message
mysql 8.0.37-0ubun... active 1 mysql 8.0/edge 253 no
mysql-router 8.0.37-0ubun... active 1 mysql-router dpe/edge 216 no
mysql-test-app 0.0.2 active 1 mysql-test-app latest/edge 46 no Last written value=54713
Unit Workload Agent Machine Public address Ports Message
mysql-test-app/0* active idle 1 10.205.193.43 Last written value=54713
mysql-router/0* active idle 10.205.193.43
mysql/0* active idle 0 10.205.193.72 3306,33060/tcp Primary
Machine State Address Inst id Base AZ Message
0 started 10.205.193.72 juju-7f1fdf-0 ubuntu@22.04 Running
1 started 10.205.193.43 juju-7f1fdf-1 ubuntu@22.04 Running
Integration provider Requirer Interface Type Message
mysql-router:cos mysql-router:cos cos peer
mysql-router:database mysql-test-app:database mysql_client subordinate
mysql-router:deprecated-shared-db-credentials mysql-router:deprecated-shared-db-credentials _deprecated_shared_db_peers peer
mysql-router:tls mysql-router:tls tls peer
mysql-router:upgrade-version-a mysql-router:upgrade-version-a upgrade peer
mysql-test-app:application-peers mysql-test-app:application-peers application-peers peer
mysql:database mysql-router:backend-database mysql_client regular
mysql:database-peers mysql:database-peers mysql_peers peer
mysql:restart mysql:restart rolling_op peer
mysql:upgrade mysql:upgrade upgrade peer
tempo-k8s:tracing mysql-router:tracing tracing regular
Note: All traces are exported to Tempo using HTTP. Support for sending traces via HTTPS is an upcoming feature.
View traces
After this is complete, the Tempo traces will be accessible from Grafana under the Explore section with tempo-k8s as the data source. You will be able to select mysql-router as the Service Name under the Search tab to view traces belonging to Charmed MySQL Router.
Below is a screenshot demonstrating a Charmed MySQL Router trace:
Feel free to read through the Tempo documentation at your leisure to explore its deployment and its integrations.