praefect

Documentation

Overview

Command praefect provides a reverse-proxy server with high-availability specific features for Gitaly.

Additionally, praefect has subcommands for common tasks:

SQL Ping

The subcommand "sql-ping" checks if the database configured in the config file is reachable:

praefect -config PATH_TO_CONFIG sql-ping

SQL Migrate

The subcommand "sql-migrate" will apply any outstanding SQL migrations.

praefect -config PATH_TO_CONFIG sql-migrate [-ignore-unknown=true|false]

By default, the migration will ignore any unknown migrations that are not known by the Praefect binary.

"-ignore-unknown=false" will disable this behavior.

The subcommand "sql-migrate-status" will show which SQL migrations have been applied and which ones have not:

praefect -config PATH_TO_CONFIG sql-migrate-status

Dial Nodes

The subcommand "dial-nodes" helps diagnose connection problems to Gitaly or Praefect. The subcommand works by sourcing the connection information from the config file, and then dialing and health checking the remote nodes.

praefect -config PATH_TO_CONFIG dial-nodes

Dataloss

The subcommand "dataloss" identifies Gitaly nodes which are missing data from the previous write-enabled primary node. It does so by looking through incomplete replication jobs. This is useful for identifying potential data loss from a failover event.

praefect -config PATH_TO_CONFIG dataloss [-virtual-storage <virtual-storage>]

"-virtual-storage" specifies which virtual storage to check for data loss. If not specified, the check is performed for every configured virtual storage.

Accept Dataloss

The subcommand "accept-dataloss" allows for accepting data loss in a repository to enable it for writing again. The current version of the repository on the authoritative storage is set to be the latest version and replications to other nodes are scheduled in order to bring them consistent with the new authoritative version.

praefect -config PATH_TO_CONFIG accept-dataloss -virtual-storage <virtual-storage> -relative-path <relative-path> -authoritative-storage <authoritative-storage>