MySQL Bugs: #93302: MySQL Router: bootstrap support for cluster with multiple cluster in metadata

Bug #93302	MySQL Router: bootstrap support for cluster with multiple cluster in metadata
Submitted:	22 Nov 2018 20:25	Modified:	24 Nov 2018 4:34
Reporter:	Frederic Descamps	Email Updates:
Status:	Verified	Impact on me:	None
Category:	MySQL Router Configuration	Severity:	S4 (Feature request)
Version:	8.0.13	OS:	Any
Assigned to:		CPU Architecture:	Any

Description:
If we setup 2 InnoDB Cluster like explained in this blog : https://lefred.be/content/migration-from-mysql-master-slave-pair-to-mysql-innodb-cluster-h...

It's not possible to boostrap mysqlrouter.

How to repeat:
So after the setup (see blog in description), we have mysql_innodb_cluster_metadata.clusters tables with 2 records:

mysql> select * from mysql_innodb_cluster_metadata.clusters\G
*************************** 1. row ***************************
         cluster_id: 1
       cluster_name: clusterDC1
 default_replicaset: 1
        description: Default Cluster
mysql_user_accounts: NULL
            options: null
         attributes: {"default": true}
*************************** 2. row ***************************
         cluster_id: 2
       cluster_name: clusterDC2
 default_replicaset: 2
        description: Default Cluster
mysql_user_accounts: NULL
            options: null
         attributes: {"default": true}

If we try too boostrap, we have the following error:

[root@mysql2 vagrant]# mysqlrouter --bootstrap clusteradmin@mysql2 --user mysqlrouter
Please enter MySQL password for clusteradmin: 
Error: Error fetching query results: Subquery returns more than 1 row (1242)

Suggested fix:
We could resolve it in two different ways:

1. run the command as above and it should find the cluster the host belongs to
2. add a parameter --clustername= to specify it

Hello Frederic,

Thank you for the report and feature request!

regards,
Umesh

If there is an offered solution for the issue or still not yet ?