Rechercher dans le manuel MySQL
21.3.3 Troubleshooting InnoDB cluster Upgrades
This section covers trouble shooting the upgrade process.
Handling Host Name Changes
MySQL Shell uses the host value of the provided connection
parameters as the target hostname used for AdminAPI
operations, namely to register the instance in the metadata
(for the dba.createCluster()
and
operations). However, the actual host used for the connection
parameters might not match the
Cluster
.addInstance()hostname
that is used or
reported by Group Replication, which uses the value of the
report_host
system variable
when it is defined (in other words it is not
NULL
), otherwise the value of
hostname
is used. Therefore,
AdminAPI now follows the same logic to register the target
instance in the metadata and as the default value for the
group_replication_local_address
variable on instances, instead of using the host value from
the instance connection parameters. When the
report_host
variable is set
to empty, Group Replication uses an empty value for the host
but AdminAPI (for example in commands such as
dba.checkInstanceConfiguration()
,
dba.configureInstance()
,
dba.createCluster()
, and so on) reports the
hostname as the value used which is inconsistent with the
value reported by Group Replication. If an empty value is set
for the report_host
system
variable, an error is generated. (Bug #28285389)
For a cluster created using a MySQL Shell version earlier than
8.0.16, an attempt to reboot the cluster from a complete
outage performed using version 8.0.16 or higher results in
this error. This is caused by a mismatch of the Metadata
values with the report_host
or hostname
values reported
by the instances. The workaround is to:
Identify which of the instances is the “seed”, in other words the one with the most recent GTID set. The
dba.rebootClusterFromCompleteOutage()
operation detects whether the instance is a seed and the operation generates an error if the current session is not connected to the most up-to-date instance.Set the
report_host
system variable to the value that is stored in the Metadata schema for the target instance. This value is thehostname:port
pair used in the instance definition upon cluster creation. The value can be consulted by querying themysql_innodb_cluster_metadata.instances
table.For example, suppose a cluster was created using the following sequence of commands:
mysql-js> \c clusterAdmin@localhost:3306 mysql-js> dba.createCluster("myCluster")
Therefore the hostname value stored in the metadata is “localhost” and for that reason,
report_host
must be set to “localhost” on the seed.Reboot the cluster using only the seed instance. At the interactive prompts do not add the remaining instances to the cluster.
Use
to add the other instances back to the cluster.Cluster
.rescan()Remove the seed instance from the cluster
Stop mysqld on the seed instance and either remove the forced
report_host
setting (step 2), or replace it with the value previously stored in the Metadata value.Restart the seed instance and add it back to the cluster using
Cluster
.addInstance()
This allows a smooth and complete upgrade of the cluster to
the latest MySQL Shell version. Another possibility, that
depends on the use-case, is to simply set the value of
report_host
on all cluster
members to match what has been registered in the Metadata
schema upon cluster creation.
Traduction non disponible
Le manuel MySQL n'est pas encore traduit en français sur l'infobrol. Seule la version anglaise est disponible pour l'instant.
Document créé le 26/06/2006, dernière modification le 26/10/2018
Source du document imprimé : https://www.gaudry.be/mysql-rf-mysql-innodb-cluster-upgrade-troubleshoot.html
L'infobrol est un site personnel dont le contenu n'engage que moi. Le texte est mis à disposition sous licence CreativeCommons(BY-NC-SA). Plus d'info sur les conditions d'utilisation et sur l'auteur.
Références
Ces références et liens indiquent des documents consultés lors de la rédaction de cette page, ou qui peuvent apporter un complément d'information, mais les auteurs de ces sources ne peuvent être tenus responsables du contenu de cette page.
L'auteur de ce site est seul responsable de la manière dont sont présentés ici les différents concepts, et des libertés qui sont prises avec les ouvrages de référence. N'oubliez pas que vous devez croiser les informations de sources multiples afin de diminuer les risques d'erreurs.