Distributed Logs

By default, Postgres logs are written to the ephemeral storage of the Patroni container, and can be accessed in the usual manner. However, this is not ideal because of the ephemeral nature of the storage, and the fact that logs from all pods are on different locations.

StackGres has created a technology stack to send Postgres and Patroni logs to a separate location, called a Distributed Logs Server. This server is represented by the CRD SGDistributedLogs. It is a separate Postgres instance, optimized for log storage, using the time-series Timescale extension to support high volume injection and automatic partitioning of logs, as well as log rotation.

This is all handled transparently for you, just go ahead and create the file sgdistributedlogs-server1.yaml to use this functionality:

apiVersion: stackgres.io/v1
kind: SGDistributedLogs
metadata:
  namespace: demo
  name: distributedlogs
spec:
  persistentVolume:
    size: 50Gi

and deploy to Kubernetes:

kubectl apply -f sgdistributedlogs-server1.yaml

This last command will trigger the creation of some resources (other than metadata). In particular, it will create a pod for storing the mentioned distributed logs:

kubectl -n demo get pods

NAME                READY   STATUS    RESTARTS   AGE
distributedlogs-0   3/3     Running   1          73s

Distributed logs server are multi-tenant: you may reference a distributed log server from more than one cluster. If used this functionality, logs will be sent to the distributed log server, and not stored in the ephemeral pod storage (other than temporarily in small buffers).

To see the distributed logs, you may view them from the Web Console, or connect via psql and query them with SQL!