ledmon - Intel(R) LED monitor service for storage enclosures.
The ledmon application is a daemon process used to monitor a state of software
RAID devices (md only) or a state of block devices. The state is visualizing
on LEDs associated to each slot in an enclosure or a drive bay. There are two
types of system: 2-LEDs system (Activity LED, Status LED) and 3-LEDs system
(Activity LED, Locate LED, Fail LED). This application has the highest
priority when accessing the LEDs.
The ledmon application uses SGPIO and SES-2 protocol to control LEDs. The
program implements IBPI patterns of SFF-8489 specification for SGPIO. Please
note some enclosures do not stick close to SFF-8489 specification. It might
happen that enclosure processor will accept IBPI pattern but it will blink
LEDs not according to SFF-8489 specification or it has limited number of
LED management (AHCI) and SAF-TE protocols are not supported.
There's no method provided to specify which RAID volume should be monitored and
which not. The ledmon application monitors all RAID devices and visualizes
The ledmon application has been verified to work with Intel(R) storage
controllers (i.e. Intel(R) AHCI controller and Intel(R) SAS controller). The
application might work with storage controllers of other vendors (especially
SAS/SCSI controllers). However storage controllers of other vendors have not
The ledmon application is part of Intel(R) Enclosure LED Utilities. Only single
instance of the application is allowed.
- -c or --config=path
- Sets a path to local configuration file. If this option is
specified the global configuration file and user configuration file has no
- -l or --log=path
- Sets a path to local log file. If this option is specified
the global log file /var/log/ledmon.log is not used.
- -t or --interval=seconds
- Sets time interval between scans of sysfs. The value is
given in seconds. The minimum is 5 seconds the maximum is not
- --quiet or --error or --warning or
--info or --debug or --all
- Verbose level - 'quiet' means no logging at all and 'all'
means to log everything. The levels are given in order. If user specifies
more then one verbose option the last option comes into effect.
- -h or --help
- Prints this text out and exits.
- -v or --version
- Displays version of ledmon and information about the
license and exits.
- Global log file, used by ledmon application. To force
logging to user defined file use -l option switch.
- User configuration file, shared between ledmon and all
ledctl application instances.
- Global configuration file, shared between ledmon and all
ledctl application instances.
Copyright (c) 2009-2013 Intel Corporation.
This program is distributed under the terms of the GNU General Public License as
published by the Free Software Foundation. See the build-in help for details
on the License and the lack of warranty.
The ledmon application does not recognize PFA state (Predicted Failure
Analysis), hence the PFA pattern from SFF-8489 specification is not
This manual page was written by Artur Wojcik <email@example.com>. It
may be used by others.