.\"	$NetBSD: rump.dhcpclient.1,v 1.4 2021/09/16 21:29:42 andvar Exp $
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.Dd January 20, 2011
.Dt RUMP.DHCPCLIENT 1
.Os
.Sh NAME
.Nm rump.dhcpclient
.Nd simple dhcp client for rump kernels
.Sh SYNOPSIS
.Nm
.Ar ifname
.Sh DESCRIPTION
The
.Nm
utility is a very simple DHCP client which can be used to apply
networking configuration on one interface in a rump kernel.
Unlike full DHCP clients,
.Nm
does not store leases or renew expired leases.
The reason for this is the typical transient nature of a rump kernel.
Additionally,
.Nm
does not save DNS resolver information.
.Pp
After having successfully configured networking,
.Nm
prints out the networking configuration and lease time and exits.
.Pp
Since
.Nm
uses
.Xr bpf 4
to send and receive raw network packets, the server must include
support for bpf and vfs (for opening
.Pa /dev/bpf ) .
Otherwise, the following diagnostic message is printed:
.Bd -literal -offset indent
rump.dhcpclient: bpf: Function not implemented
.Ed
.Sh SEE ALSO
.Xr rump_server 1 ,
.Xr bpf 4
.Sh CAVEATS
There is no easy way to release a lease.