stacd

  nvme-stas 3.0

Name

stacd — STorage Appliance Connector

Synopsis

stacd [OPTIONS…]

Description

stacd is a system daemon that can be used to automatically connect to NVMe-oF I/O Controllers using the discovery log pages collected by stafd(8). It can also be manually configured with stacd.conf(5) to connect to I/O Controllers that otherwise cannot be found automatically.

Options

The following options are understood:

-h, --help

Print the help text and exit.

--version

Print the version string and exit.

-fFILE, --conf-file=FILE Specify a different configuration file than stacd.conf(5) (default: /etc/stas/stacd.conf).

-s, --syslog Send messages to syslog instead of stdout. Use this when running stacd as a daemon. (default: “false”).

--tron Trace ON. (default: “false”)

--idl=FILE Print D-Bus IDL to FILE and exit.

Exit status

On success, 0 is returned, a non-zero failure code otherwise.

Daemonization

stacd is managed by systemd. The following operations are supported:

**Table 1. **

Command

Description

 
$ systemctl start stacd

Start daemon.

 
$ systemctl stop stacd

Stop daemon. The SIGTERM signal is used to tell the daemon to stop.

 
$ systemctl restart stacd

Effectively a stop + start.

 
$ systemctl reload stacd

Reload configuration. This is done in real time without restarting the daemon. The SIGHUP signal is used to tell the daemon to reload its configuration file. Note that configuration parameters that affect connections (e.g. kato), will not apply to existing connections. Only connections established after the configuration was changed will utilize the new configuration parameters.

Design

stacd uses the GLib main loop. The GLib Python module provides several low-level building blocks that stacd requires. In addition, many Python modules “play nice” with GLib such as dasbus (D-Bus package) and pyudev (UDev package). GLib also provides additional components such as timers, signal handlers, and much more.

Configuration

stacd can automatically set up the I/O connections to discovered storage subsystems. However, stacd can also operate in a non-automatic mode based on manually entered configuration. In other words, storage subsystems can be entered in a configuration file named /etc/stas/stacd.conf. This configuration file also provides additional parameters, as log-level attributes used for debugging purposes.

D-Bus API

The interface to stacd is D-Bus. This allows other programs, such as stacctl, to communicate with stacd. The D-Bus address is org.nvmexpress.stac.

See Also

stacd.conf(5), stacd.service(8), stacctl(1), stafd(8), org.nvmexpress.stac(5).