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.Dd July 24, 2017
.Dt ZGENHOSTID 8 SMM
.Os Linux
.Sh NAME
.Nm zgenhostid
.Nd generate and store a hostid in
.Em /etc/hostid
.Sh SYNOPSIS
.Nm
.Op Ar hostid
.Sh DESCRIPTION
If
.Em /etc/hostid
does not exist, create it and store a hostid in it.  If the user provides
.Op Ar hostid
on the command line, store that value.  Otherwise, randomly generate a
value to store.
.Pp
This emulates the
.Xr genhostid 1
utility and is provided for use on systems which do not include the utility.
.Pp
.Sh OPTIONS
.Op Ar hostid
Specifies the value to be placed in
.Em /etc/hostid .
It must be a number with a value between 1 and 2^32-1.  This value
.Sy must
be unique among your systems.  It must be expressed in hexadecimal and be
exactly 8 digits long.
.Sh EXAMPLES
.Bl -tag -width Ds
.It Generate a random hostid and store it
.Bd -literal
# zgenhostid
.Ed
.It Record the libc-generated hostid in Em /etc/hostid
.Bd -literal
# zgenhostid $(hostid)
.Ed
.It Record a custom hostid (0xdeadbeef) in Em etc/hostid
.Bd -literal
# zgenhostid deadbeef
.Ed
.El
.Sh SEE ALSO
.Xr spl-module-parameters 5 ,
.Xr genhostid 1 ,
.Xr hostid 1