zgenhostid.8: revisit

Reviewed-by: Richard Laager <rlaager@wiktel.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Closes #12212
This commit is contained in:
наб 2021-06-04 22:43:21 +02:00 committed by Brian Behlendorf
parent 1b37cc1abe
commit 4b7ed6a286

View File

@ -18,72 +18,78 @@
.\"
.\" CDDL HEADER END
.\"
.\"
.\" Copyright (c) 2017 by Lawrence Livermore National Security, LLC.
.\"
.Dd May 26, 2021
.Dt ZGENHOSTID 8 SMM
.Dt ZGENHOSTID 8
.Os
.
.Sh NAME
.Nm zgenhostid
.Nd generate and store a hostid in
.Em /etc/hostid
.Nd generate host ID into /etc/hostid
.Sh SYNOPSIS
.Nm
.Op Fl f
.Op Fl o Ar filename
.Op Ar hostid
.
.Sh DESCRIPTION
Creates
.Pa /etc/hostid
file and stores hostid in it.
If the user provides
.Op Ar hostid
on the command line, validates and stores that value.
Otherwise, randomly generates a value to store.
.Bl -tag -width "hostid"
file and stores the host ID in it.
If
.Ar hostid
was provided, validate and store that value.
Otherwise, randomly generate an ID.
.
.Sh OPTIONS
.Bl -tag -width "-o filename"
.It Fl h
Display a summary of the command-line options.
.It Fl f
Force file overwrite.
Allow output overwrite.
.It Fl o Ar filename
Write to
.Pa filename
instead of default
.Pa /etc/hostid
instead of the default
.Pa /etc/hostid .
.It Ar hostid
Specifies the value to be placed in
.Pa /etc/hostid .
It should be a number with a value between 1 and 2^32-1.
If it is 0, zgenhostid will generate a random hostid.
If
.Sy 0 ,
generate a random ID.
This value
.Sy must
.Em must
be unique among your systems.
It
.Sy must
be expressed in hexadecimal and be exactly
.Em 8
digits long, optionally prefixed by
.Em 0x .
.Em must
be an 8-digit-long hexadecimal number, optionally prefixed by
.Qq 0x .
.El
.
.Sh FILES
.Pa /etc/hostid
.
.Sh EXAMPLES
.Bl -tag -width Bd
.It Generate a random hostid and store it
.Dl # zgenhostid
.Dl # Nm
.It Record the libc-generated hostid in Pa /etc/hostid
.Dl # zgenhostid "$(hostid)"
.It Record a custom hostid (0xdeadbeef) in Pa /etc/hostid
.Dl # zgenhostid deadbeef
.It Record a custom hostid (0x01234567) in Pa /tmp/hostid No and ovewrite the file if it exists
.Dl # zgenhostid -f -o /tmp/hostid 0x01234567
.Dl # Nm Qq $ Ns Pq Nm hostid
.It Record a custom hostid Po Ar 0xdeadbeef Pc in Pa /etc/hostid
.Dl # Nm Ar deadbeef
.It Record a custom hostid Po Ar 0x01234567 Pc in Pa /tmp/hostid No and ovewrite the file if it exists
.Dl # Nm Fl f o Ar /tmp/hostid 0x01234567
.El
.
.Sh SEE ALSO
.Xr genhostid 1 ,
.Xr hostid 1 ,
.Xr sethostid 3 ,
.Xr spl 4
.
.Sh HISTORY
.Nm
emulates the
@ -91,4 +97,4 @@ emulates the
utility and is provided for use on systems which
do not include the utility or do not provide the
.Xr sethostid 3
call.
function.