How to login to Clickhouse Database

Products

• VMware Tanzu Platform - Hub

Issue/Introduction

This KB discuss how to login to Clickhouse Database for troubleshooting purposes.

Cause

Resolution

These are the steps to login to Clickhouse Database which can be used during troubleshooting purposes.

1. ssh into Tanzu hub's registry vm

   bosh -d hub-####### ssh registry/0

2. (Optional) Check health first to ensure you have no issues with the cluster

   kubectl cluster-info 
   
   kubectl get nodes -n tanzusm
   
   kubectl get pods -n tanzusm 

3. Get pod name

   kubectl get pods -n tanzusm | grep clickhouse 

4. Get password:

   kubectl get secret clickhouse-secret -n tanzusm -o jsonpath='{.data.password}' | base64 --decode; echo ""

5. Login using clickhouse-client specify the pod name from Step 3. It will prompt for password, use the password from Step 4

   kubectl exec -it <chi-clickhouse-metrics-pod-name> -n tanzusm -- clickhouse-client 

Useful query commands:

SHOW DATABASES;
SHOW TABLES from <database-name>;

CRITICAL: Making direct structural or data modifications to the clickhouse database is strictly discouraged and can cause severe, irreversible system issues.