How to check whether the k3s cluster is running with embedded etcd or SQlite or External (MySQL/PostgreSQL)

K3S 

How to check whether the k3s cluster is running with embedded etcd or SQlite or External (MySQL/PostgreSQL)

K3s supports the following datastore options:

• Embedded SQLite:  SQLite cannot be used on clusters with multiple servers.
• Embedded etcd: Basically for HA cluster, Embedded etcd will be automatically selected if K3s is configured to initialize a new etcd cluster
• External Database; High availability DB 

1. Here are the few command line options:  

#journalctl -u k3s.service --no-pager | grep "database"

• If the logs show "Running embedded etcd or Defragmenting etcd database", K3s is using etcd.
•  If you see references to SQLite or kine, it's using SQLite.
• There are no etcd status conditions when using kine. With kine, the datastore is always considered healthy. If the database is not available, k3s will fail to start, or exit if previously running.

2. Another option is:

# cat /etc/systemd/system/k3s.service | grep 'ExecStart'

•  If the output contains --datastore-endpoint, K3s is using an external database (MySQL/PostgreSQL).
•  If --datastore-endpoint is NOT set, K3s is using an embedded database which could be either SQLite (single-node) or etcd (HA mode).

3. Another option: 

# ls -l /var/lib/rancher/k3s/server/db/ 

• If you see a file named k3s.db, K3s is using SQLite

4. Another option:

# etcdctl member list  

• If this returns a list of members, K3s is running with embedded etcd.

faq

Applicable only for k3s