.\" .\" Copyright (c) 2003 Poul-Henning Kamp .\" Copyright (c) 2017 Alexander Motin .\" All rights reserved. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions .\" are met: .\" 1. Redistributions of source code must retain the above copyright .\" notice, this list of conditions and the following disclaimer. .\" 2. Redistributions in binary form must reproduce the above copyright .\" notice, this list of conditions and the following disclaimer in the .\" documentation and/or other materials provided with the distribution. .\" 3. The names of the authors may not be used to endorse or promote .\" products derived from this software without specific prior written .\" permission. .\" .\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE .\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF .\" SUCH DAMAGE. .\" .Dd March 5, 2024 .Dt DISKINFO 8 .Os .Sh NAME .Nm diskinfo .Nd get information about disk device .Sh SYNOPSIS .Nm .Op Fl citSvw .Ar disk ... .Nm .Op Fl l .Fl p .Ar disk ... .Nm .Op Fl l .Fl s .Ar disk ... .Sh DESCRIPTION The .Nm utility prints out information about a disk device, and optionally runs a naive performance test on the device. .Pp The following options are available: .Bl -tag -width ".Fl v" .It Fl v Print fields one per line with a descriptive comment. .It Fl c Perform a simple measurement of the I/O read command overhead. .It Fl i Perform a simple IOPS benchmark. .It Fl l In case of .Fl p or .Fl s modes prepend each line of an output with a device name using a tab character as a separator. .It Fl p Return the physical path of the disk. This is a string that identifies the physical path to the disk in the storage enclosure. .It Fl s Return the disk ident, usually the serial number. .It Fl S Perform synchronous random write test (ZFS SLOG test), measuring time required to write data blocks of different size and flush disk cache. Blocks of more then 128KB are written with multiple parallel operations. .It Fl t Perform a simple and rather naive benchmark of the disks seek and transfer performance. .It Fl w Allow disruptive write tests. .El .Pp If given no arguments, the output will be a single line per specified device with the following fields: device name, sectorsize, media size in bytes, media size in sectors, stripe size, stripe offset, firmware cylinders, firmware heads, and firmware sectors. The last three fields are only present if the information is available. .Sh EXAMPLES List first ten (at most) .Xr da 4 devices with corresponding serial numbers: .Pp .Dl diskinfo -ls /dev/da? .Sh SEE ALSO .Xr da 4 .Sh HISTORY The .Nm command appeared in .Fx 5.1 . .Sh AUTHORS The .Nm utility was written by .An Poul-Henning Kamp Aq Mt phk@FreeBSD.org . .Sh BUGS There are in order of increasing severity: lies, damn lies, statistics, and computer benchmarks.