# Reference - [Galera Cluster Status Variables](https://mariadb.com/docs/galera-cluster/reference/galera-cluster-status-variables.md): Reference for MariaDB Galera Cluster status variables exposed via SHOW STATUS LIKE 'wsrep%', covering applier threads, certification, flow control, replication queues, and node state. - [Galera Cluster System Variables](https://mariadb.com/docs/galera-cluster/reference/galera-cluster-system-variables.md): Complete Galera Cluster System Variables reference for MariaDB. Complete guide for configuration values, scope settings, and performance impact. - [WSREP Variable Details](https://mariadb.com/docs/galera-cluster/reference/wsrep-variable-details.md): Per-option reference pages for MariaDB Galera Cluster wsrep\_provider\_options and wsrep\_\* system variables, including defaults, dynamic-update support, scope, data types, and usage examples. - [wsrep\_certificate\_expiration\_hours\_warning](https://mariadb.com/docs/galera-cluster/reference/wsrep-variable-details/wsrep_certificate_expiration_hours_warning.md): wsrep\_certificate\_expiration\_hours\_warning configures Galera Cluster to log a warning when the node's wsrep X.509 certificate expires within the given number of hours; 0 disables warnings. - [wsrep\_cluster\_name](https://mariadb.com/docs/galera-cluster/reference/wsrep-variable-details/wsrep_cluster_name.md): wsrep\_cluster\_name is the dynamic global system variable that sets the logical cluster name; all Galera Cluster nodes must share the same value to form a Primary Component. - [wsrep\_provider\_options](https://mariadb.com/docs/galera-cluster/reference/wsrep-variable-details/wsrep_provider_options.md): wsrep\_provider\_options holds the semicolon-separated list of Galera wsrep provider settings; this reference catalogs every supported option, its default, and whether it is dynamic. - [wsrep\_ssl\_mode](https://mariadb.com/docs/galera-cluster/reference/wsrep-variable-details/wsrep_ssl_mode.md): wsrep\_ssl\_mode selects the TLS implementation for Galera wsrep traffic in MariaDB 11.4 and 10.6: PROVIDER for built-in TLS, SERVER for server TLS, or SERVER\_X509 with X.509 verification. - [wsrep\_sst\_method](https://mariadb.com/docs/galera-cluster/reference/wsrep-variable-details/wsrep_sst_method.md): wsrep\_sst\_method selects the State Snapshot Transfer method used by Galera Cluster, with rsync as the default; it is dynamic and global, and should match between donor and joiner nodes. - [wsrep\_sst\_common](https://mariadb.com/docs/galera-cluster/reference/wsrep-variable-details/wsrep_sst_common.md): wsrep\_sst\_common provides shared SST functionality across Galera methods, parsing authentication credentials and TLS-related options like tca, tcapath, tcert, and tkey for secure transfers. - [wsrep\_sst\_mariabackup](https://mariadb.com/docs/galera-cluster/reference/wsrep-variable-details/wsrep_sst_mariabackup.md): wsrep\_sst\_mariabackup script options control the mariadb-backup SST data transfer: stream format, transfer utility (socat), socket options, progress logging, and timing instrumentation. - [gcs.check\_appl\_proto](https://mariadb.com/docs/galera-cluster/reference/wsrep-variable-details/gcs.check_appl_proto.md): gcs.check\_appl\_proto controls application-level protocol checks when joining a Galera cluster; set to FALSE to allow rolling migrations between MySQL and MariaDB Galera nodes. - [socket.ssl](https://mariadb.com/docs/galera-cluster/reference/wsrep-variable-details/socket.ssl.md): The socket.ssl wsrep\_provider\_options entry enables TLS encryption for Galera Cluster replication traffic; it defaults to NO and cannot be changed dynamically. - [socket.ssl\_ca](https://mariadb.com/docs/galera-cluster/reference/wsrep-variable-details/socket.ssl_ca.md): socket.ssl\_ca sets the path to the SSL Certificate Authority file used to verify the wsrep peer certificate; it must be in PEM format and is non-dynamic. - [socket.ssl\_cert](https://mariadb.com/docs/galera-cluster/reference/wsrep-variable-details/socket.ssl_cert.md): socket.ssl\_cert sets the path to the node's SSL certificate used by the wsrep provider to encrypt Galera replication traffic; it must be in PEM format and is non-dynamic. - [socket.ssl\_key](https://mariadb.com/docs/galera-cluster/reference/wsrep-variable-details/socket.ssl_key.md): socket.ssl\_key sets the path to the node's SSL private key paired with socket.ssl\_cert for encrypting Galera replication traffic; it must be in PEM format and is non-dynamic. - [ssl\_ca](https://mariadb.com/docs/galera-cluster/reference/wsrep-variable-details/ssl_ca.md): ssl\_ca sets the server-side path to the SSL Certificate Authority file in PEM format used by MariaDB Server, including for Galera TLS when wsrep\_ssl\_mode is SERVER or SERVER\_X509. - [ssl\_capath](https://mariadb.com/docs/galera-cluster/reference/wsrep-variable-details/ssl_capath.md): ssl\_capath sets the server-side path to a directory of SSL Certificate Authority files used by MariaDB Server, including for Galera TLS when wsrep\_ssl\_mode is SERVER or SERVER\_X509. - [ssl\_cert](https://mariadb.com/docs/galera-cluster/reference/wsrep-variable-details/ssl_cert.md): ssl\_cert sets the server-side path to the X509 SSL certificate in PEM format used by MariaDB Server, including for Galera TLS when wsrep\_ssl\_mode is SERVER or SERVER\_X509. - [ssl\_key](https://mariadb.com/docs/galera-cluster/reference/wsrep-variable-details/ssl_key.md): ssl\_key sets the server-side path to the X509 SSL private key in PEM format used by MariaDB Server, including for Galera TLS when wsrep\_ssl\_mode is SERVER or SERVER\_X509. - [Galera Cluster System Tables](https://mariadb.com/docs/galera-cluster/reference/galera-cluster-system-tables.md): Reference for the wsrep system tables in the mysql database, including wsrep\_cluster, wsrep\_cluster\_members, wsrep\_streaming\_log, and the writable wsrep\_allowlist for joiner IP control. - [Known Limitations](https://mariadb.com/docs/galera-cluster/reference/mariadb-galera-cluster-known-limitations.md): Known limitations of MariaDB Galera Cluster: InnoDB-only restriction, transaction-size and write-set caps, isolation anomalies like lost updates and stale reads, and unsupported features. - [MariaDB Advanced Cluster: Team FAQ & Architectural Guide](https://mariadb.com/docs/galera-cluster/reference/mariadb-advanced-cluster-team-faq-and-architectural-guide.md): FAQ and architectural guide for MariaDB Advanced Cluster (Tech Preview), the Raft-based high-availability product replacing synchronous replication for global, WAN-scale deployments. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. 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