IPCONFIG(8)                                           IPCONFIG(8)

          ipconfig, rip, linklocal - Internet configuration and

         ip/ipconfig [-6DGNOPdnpruX] [-b baud] [-c ctl] [-g gateway]
            [-h host] [-m mtu] [-o dhcp-opt] [-f dbfile] [-x netmtpt]
            [ type [ device ]] [verb] [ local [ mask [ remote [ file-
            server [ auth ]]]]]

          ip/rip [-bdr] [-x netmtpt]

          ip/linklocal [ -t gwipv4 ] mac ...

          Ipconfig binds a device interface to a mounted IP stack
          (default /net) and configures the interface with a local
          address and optionally a mask, a remote address, a file
          server and an authentication server address.  If no device
          is specified, the first ether device on the mounted IP stack
          is used.  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.
          Information from DHCP and IPv6 router advertisements is
          written to /net/ndb in the form of an ndb(8) entry unless
          the P flag has been specified.

          Type may be ether, gbe, ppp, pkt, or loopback.  The gbe type
          is equivalent to ether except that it allows jumbo packets
          (up to ~9KB).  The pkt interface passes all IP packets to
          and from a user program.  For ppp the device can be any byte
          stream device.

          The verb (default add) determines the action performed.  The
          usual 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 IPv6-specific verbs, which take different arguments,

          add6 prefix pfx-len onlink auto validlt preflt
               sets the named IPv6 parameters; see ip(3) for more

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     IPCONFIG(8)                                           IPCONFIG(8)


          ra6 [ keyword value ] ...
               sets IPv6 router advertisement parameter keyword's
               value. See ip(3) for more detail.  Setting recvra non-
               zero also forks a process to receive and process router
               advertisements.  Setting sendra non-zero also enables
               IP routing on the interface, forks a process to send
               router advertisements, and if no recvra process is run-
               ning, forks one.

          The options are:

          6  if adding an address (the default action), add the IPv6
             link-local address.

          b  the baud rate to use on a serial line when configuring

          c  write the control string ctl to the ethernet device con-
             trol file before starting to configure it.  May be
             repeated to specify multiple control writes.

          d  use DHCP to determine any unspecified configuration

          D  turn on debugging.

          g  the default gateway.

          G  use only generic DHCP and RA options.  Without this
             option, ipconfig adds to requests a Vendor Class option
             with value plan9_$cputype and also requests vendor spe-
             cific 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.

          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.

          m  the maximum IP packet size to use on this interface.

          n  determine parameters but don't configure the interface.

          N  look in dbfile (default /lib/ndb/local) for the IP param-
             eters for the specified local IP address or if local is
             omited and the device is an ethernet then all IP parame-
             ters associated with the MAC address. IPv6 addresses are
             added only if a IPv6 link-local address exists on the

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     IPCONFIG(8)                                           IPCONFIG(8)

             interface or the 6 flag has been given to automatically
             configure one.

          O  addresses specified on the command line override those
             obtained via DHCP.  A command line address of 0 implies
             no override.

          p  write configuration information to /net/ndb.

          P  do not write configuration information to /net/ndb.

          r  by default, ipconfig exits after trying DHCP for 15 sec-
             onds with no answer.  This option directs ipconfig
             instead to fork a background process that keeps trying

          u  disable IPv6 duplicate discovery detection, which removes
             any existing ARP table entry for one of our IPv6
             addresses before adding new ones.

          f  use the ndb database file dbfile.

          x  use the IP stack mounted at netmtpt instead of at /net.

          X  don't fork a process to keep the DHCP lease alive.

          o  adds dhcpoption to the list of paramters requested of the
             DHCP server.  The result will appear in /net/ndb should
             this be the first interface.  The known options are:

             arptimeout, baddr, bflen, bootfile, clientid, cookie,
             discovermask, discoverrouter, dns, dom, dumpfile,
             etherencap, extpath, finger, homeagent, impress, ipaddr,
             ipforward, ipgw, ipmask, irc, lease, log, lpr, maxdata-
             gram, maxmsg, message, mtu, name, netbiosdds, netbiosns,
             netbiosscope, netbiostype, ni, nisdomain, nisplus, nis-
             plusdomain, nntp, nonlocal, ntp, overload, params, path-
             plateau, pathtimeout, policyfilter, pop3, rebindingtime,
             renewaltime, rl, rootpath, rs, serverid, smtp, st, stati-
             croutes, stdar, subnetslocal, supplymask, swap, sys,
             tcpka, tcpkag, tcpttl, tftp, time, timeoff, trailerencap,
             ttl, type, vendorclass, www, xdispmanager, xfont

             The options ipmask, ipgw, dns, sys, and ntp are always

          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-

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     IPCONFIG(8)                                           IPCONFIG(8)

          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 network.

          x  use the IP stack mounted at netmtpt instead of at /net.

          d  turn on (voluminous) debugging.

          Linklocal prints the IPv6 link-local address corresponding
          to the given mac address.  Given -t, linklocal instead
          prints the 6to4 EUI-64-based IPv6 address corresponding to
          mac and 6to4 gateway gwipv4.

          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
               % ndb/cs
               % ndb/dns -r

          Add a second address to the stack.

               % ip/ipconfig ether /net/ether0 add

          At Bell Labs, our primary IP stack is always to the
          company's internal firewall-protected network.  The follow-
          ing creates an external IP stack to directly access the out-
          side Internet.  Note that the connection server uses a dif-
          ferent 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 ether /net.alt/ether1\
               % 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

          Configure the IPv6 link-local address automatically and lis-
          ten for router announcements.

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     IPCONFIG(8)                                           IPCONFIG(8)

               ip/ipconfig -6
               ip/ipconfig ra6 recvra 1



          ether(3), ip(3), loopback(3), ndb(6), 6in4(8), dhcpd(8),
          /lib/rfc/rfc2373 for IPv6's modified EUI-64

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