IPCONFIG(8) IPCONFIG(8)
NAME
ipconfig, rip - Internet configuration and routing
SYNOPSIS
ip/ipconfig [-ndDrG] [-b baud] [-m mtu] [-g gateway] [-h
hostname] [-x netmtpt] type device [verb] [local-addr]
[mask] [remote-addr] [file-server-addr] [auth-server-addr]
ip/rip [-bdr] [-x netmtpt]
DESCRIPTION
Ipconfig binds a device interface (default /net/ether0) to a
mounted IP stack (default /net) and configures the interface
with a local address, a mask, and a remote address. The
addresses can be specified in the command line or obtained
via DHCP. If DHCP is requested, it will also obtain the
addresses of DNS servers, NTP servers, gateways, a Plan 9
file server, and a Plan 9 authentication server. If this is
the first interface on the IP stack, the information will be
written to /net/ndb in the form of an ndb(8) entry.
Type may be ether, ppp, or gbe. The gbe type is equivalent
to ether except that it allows jumbo packets. For ppp the
device can be any byte stream device.
The verb (default add) determines the action performed. The
verbs are:
add if the device is not bound to the IP stack, bind it.
Add the given local address, mask, and remote address
to the interface. An interface may have multiple
addresses.
remove
remove the address from the device interface.
unbind
unbind the device interface and all its addresses from
the IP stack.
The options are:
x use the IP stack mounted at netmtpt instead of at /net.
g the default gateway.
d use DHCP to determine any unspecified configuration
parameters.
r by default, ipconfig exits after trying DHCP for 15
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IPCONFIG(8) IPCONFIG(8)
seconds with no answer. This option directs ipconfig
instead to fork a background process that keeps trying
forever.
h the hostname to add to DHCP requests. Some DHCP
servers, such as the one used by COMCAST, will not
respond unless a correct hostname is in the request.
n determine parameters but don't configure the interface.
b the baud rate to use on a serial line when configuring
PPP.
D turn on debugging.
G use only generic DHCP options. Without this option,
ipconfig adds to requests a Vendor Class option with
value plan9_$cputype and also requests vendor specific
options 128 and 129 which we interpret as the Plan 9
file server and auth server. Replies to these options
contain a list of IP addresses for possible file
servers and auth servers.
m the maximum IP packet size to use on this interface.
If DHCP is requested, a process is forked off to renew the
lease before it runs out. If the lease does run out, this
process will remove any configured addresses from the inter-
face.
Rip runs the routing protocol RIP. It listens for RIP pack-
ets on connected networks and updates the kernel routing
tables. The options are:
b broadcasts routing information onto the networks.
n gathers routing information but doesn't write to the
route table. This is useful with -d to debug a net-
work.
x use the IP stack mounted at netmtpt instead of at /net.
d turn on (voluminous) debugging.
EXAMPLE
Configure Ethernet 0 as the primary IP interface. Get all
addresses via DHCP. Start up a connection server and DNS
resolver for this IP stack.
% bind -b '#l0' /net
% bind -a '#I0' /net
% ip/ipconfig
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IPCONFIG(8) IPCONFIG(8)
% ndb/cs
% ndb/dns -r
Add a second address to the stack.
% ip/ipconfig ether /net/ether0 add 12.1.1.2 255.255.255.0
At Lucent our primary IP stack is always to the company's
internal firewall-protected network. The following creates
an external IP stack to directly access the outside Inter-
net. Note that the connection server uses a different set
of ndb files. This prevents us from confusing inside and
outside name/address bindings.
% bind -b '#l1' /net.alt
% bind -b '#I1' /net.alt
% ip/ipconfig -x /net.alt -g 204.178.31.1 ether /net.alt/ether1\
204.178.31.6 255.255.255.0
% ndb/cs -x /net.alt -f /lib/ndb/external
% ndb/dns -sx /net.alt -f /lib/ndb/external
% aux/listen -d /rc/bin/service.alt /net.alt/tcp
% aux/listen -d /rc/bin/service.alt /net.alt/il
SOURCE
/sys/src/cmd/ip/ipconfig.c
/sys/src/cmd/ip/rip.c
SEE ALSO
ndb(6)
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