Usage

CLI Overview

Note

The zrepl binary is self-documenting: run zrepl help for an overview of the available subcommands or zrepl SUBCOMMAND --help for information on available flags, etc.

Subcommand	Description
`zrepl help`	show subcommand overview
`zrepl daemon`	run the daemon, required for all zrepl functionality
`zrepl status`	show job activity, or with `--raw` for JSON output
`zrepl stdinserver`	see ssh+stdinserver Transport
`zrepl signal wakeup JOB`	manually trigger replication + pruning of JOB
`zrepl signal reset JOB`	manually abort current replication + pruning of JOB
`zrepl configcheck`	check if config can be parsed without errors
`zrepl migrate`	perform on-disk state / ZFS property migrations (see changelog for details)
`zrepl zfs-abstraction`	list and remove zrepl’s abstractions on top of ZFS, e.g. holds and step bookmarks (see overview )

zrepl daemon

All actual work zrepl does is performed by a daemon process. The daemon supports structured logging and provides monitoring endpoints.

When installing from a package, the package maintainer should have provided an init script / systemd.service file. You should thus be able to start zrepl daemon using your init system.

Alternatively, or for running zrepl in the foreground, simply execute zrepl daemon. Note that you won’t see much output with the default logging configuration:

Attention

Make sure to actually monitor the error level output of zrepl: some configuration errors will not make the daemon exit.

Example: if the daemon cannot create the ssh+stdinserver Transport sockets in the runtime directory, it will emit an error message but not exit because other tasks such as periodic snapshots & pruning are of equal importance.

Restarting

The daemon handles SIGINT and SIGTERM for graceful shutdown. Graceful shutdown means at worst that a job will not be rescheduled for the next interval. The daemon exits as soon as all jobs have reported shut down.

Systemd Unit File

A systemd service definition template is available in dist/systemd. Note that some of the options only work on recent versions of systemd. Any help & improvements are very welcome, see issue #145.