rtadvd(8) [opendarwin man page]
RTADVD(8) BSD System Manager's Manual RTADVD(8) NAME
rtadvd -- router advertisement daemon SYNOPSIS
rtadvd [-dDfMRs] [-c configfile] interface ... DESCRIPTION
rtadvd sends router advertisement packets to the specified interfaces. The program will daemonize itself on invocation. It will then send router advertisement packets periodically, as well as in response to router solicitation messages sent by end hosts. Router advertisements can be configured on a per-interface basis, as described in rtadvd.conf(5). If there is no configuration file entry for an interface, or if the configuration file does not exist altogether, rtadvd sets all the parame- ters to their default values. In particular, rtadvd reads all the interface routes from the routing table and advertises them as on-link prefixes. rtadvd also watches the routing table. By default, if an interface direct route is added/deleted on an advertising interface and no static prefixes are specified by the configuration file, rtadvd adds/deletes the corresponding prefix to/from its advertising list, respectively. The -s option may be used to disable this behavior. Moreover, if the status of an advertising interface changes, rtadvd will start or stop sending router advertisements according to the latest status. Basically, hosts MUST NOT send Router Advertisement messages at any time (RFC 2461, Section 6.2.3). However, it would sometimes be useful to allow hosts to advertise some parameters such as prefix information and link MTU. Thus, rtadvd can be invoked if router lifetime is explic- itly set zero on every advertising interface. The command line options are: -c Specify an alternate location, configfile, for the configuration file. By default, /etc/rtadvd.conf is used. -d Print debugging information. -D Even more debugging information is printed. -f Foreground mode (useful when debugging). -M Specify an interface to join the all-routers site-local multicast group. By default, rtadvd tries to join the first advertising interface appeared in the command line. This option has meaning only with the -R option, which enables routing renumbering protocol support. -R Accept router renumbering requests. If you enable it, certain IPsec setup is suggested for security reasons. On KAME-based systems, rrenumd(8) generates router renumbering request packets. This option is currently disabled, and is ignored by rtadvd with a warning message. -s Do not add or delete prefixes dynamically. Only statically configured prefixes, if any, will be advertised. Upon receipt of signal SIGUSR1, rtadvd will dump the current internal state into /var/run/rtadvd.dump. Use SIGTERM to kill rtadvd gracefully. In this case, rtadvd will transmit router advertisement with router lifetime 0 to all the interfaces (in accordance with RFC2461 6.2.5). DIAGNOSTICS
The rtadvd utility exits 0 on success, and >0 if an error occurs. FILES
/etc/rtadvd.conf The default configuration file. /var/run/rtadvd.pid contains the pid of the currently running rtadvd. /var/run/rtadvd.dump in which rtadvd dumps its internal state. SEE ALSO
rtadvd.conf(5), rrenumd(8), rtsol(8) HISTORY
The rtadvd command first appeared in WIDE Hydrangea IPv6 protocol stack kit. CAVEAT
There used to be some text that recommended users not to let rtadvd advertise Router Advertisement messages on an upstream link to avoid undesirable icmp6(4) redirect messages. However, based on the later discussion in the IETF ipng working group, all routers should rather advertise the messages regardless of the network topology, in order to ensure reachability. BSD
May 17, 1998 BSD
Check Out this Related Man Page
ip6config(8) BSD System Manager's Manual ip6config(8) NAME
ip6config -- Configure IPv6 and 6to4 IPv6 tunnelling SYNOPSIS
ip6config [-h] command interface DESCRIPTION
The ip6config script can be used to start up or shut down IPv6 on active interfaces. It can also be used to configure a 6to4 tunnel and start or stop router advertisement. When IPv6 is enabled on an interface the protocol is attached to the interface, at which point the default settings in the kernel allow it to acquire a link-local address and listen for router advertisements. 6to4 is a mechanism by which your IPv6 address(es) are derived from an assigned IPv4 address, and which involves automatic tunnelling to one or more remove 6to4 hubs, which will then forward your v6 packets on the 6bone etc. Replies are routed back to you over IPv4 via (possibly) other 6to4 capable remote gateways. As such, IPv6-in-IPv4-encapsulated packets are accepted from all v4-hosts. From your (single) IPv4 address, you get a whole IPv6 /48 network, which allows you to split your network in 2^16 subnets, with 2^64 hosts each. You need to setup routing for your internal network properly, help is provided for setting up the border router here. This script takes the burden to calculate your IPv6 address from existing IPv4 address and runs the commands to setup (and tear down) auto- matic 6to4 IPv6 tunnelling. Finally, router advertisement for an internal network can be started and stopped. This uses sysctl to set net.inet6.ip6.forwarding and net.inet6.ip6.accept_rtadv to the proper values for routing. Possible options are: -h Show usage. Possible commands are: start-v6 Start IPv6 on given interface using default kernel settings. Attaches protocol to the interface. If interface is "all", all valid interfaces will be configured. stop-v6 Stop IPv6 on given interface. Detaches protocol from the interface. If interface is "all", all valid interfaces will be config- ured. start-stf Configure 6to4 IPv6. The stf(4) interface is configured, and a default route to a remote 6to4 gateway is established. In addi- tion, the internal network interface is assigned an address. stop-stf Stops 6to4 IPv6. All addresses are removed from the stf(4) device, and the default route is removed. start-rtadvd Starts router advertizement and IPv6 packet forwarding, turning the machine into a IPv6 router. rtadvd(8) is invoked with a custom config file created under /var/run. Clients just need to be told to accept router advertizements, i.e. the 'net.inet6.ip6.accept_rtadv' sysctl needs to be set to '1'. You can arrange that by setting ``ip6mode=autohost'' in /etc/rc.conf. stop-rtadvd Stops router advertizement and IPv6 packet forwarding. rtadvd(8) is stopped, and the rtadvd.conf(5) config file is removed from /var/run. REQUIREMENTS
Besides IPv4 connectivity, you need support for IPv6 and the stf(4) device in your kernel. This is provided beginning with Darwin Kernel Ver- sion 6.0. No special values are needed in /etc/rc.conf to run this script, but see comment on setting up IPv6-clients 'behind' your 6to4 router for the rtadvd-start command! CONFIGURATION
The default IPv6 configuration for an interface assigns a link-local address to it and sets the interface to receive router advertisements. No further configuration is necessary for basic functionality. However, various settings can be modified by using sysctl. The ip6config script reads its 6to4 configuration from a config file named 6to4.conf. The 6to4.conf file is in perl(1) syntax, and contains several variables that can be tuned to adjust your setup. in_if The inside interface. If non-empty, this interface is assigned the IPv6 address 2002:x:x:v6_innernet:hostbits6, see below. This is only useful on machines that have more than one network interface, e.g. with a modem and a local ethernet. v6_net The subnet address you want to use on the address of your outbound interface. Defaults to ``1''. v6_innernet The subnet address you want to use on the address of your inbound interface. Defaults to ``2''. hostbits6 The lower 64 bits of both the inbound and outbound interface's addresses. peer Name of the remote 6to4 server that'll take our IPv6-in-IPv4 encapsulated packets and route them on via IPv6. A special value of ``6to4-anycast'' can be used for the anycast service defined in RFC 3068. Other possible values are given in the example config file. SEE ALSO
stf(4), ``6to4 IPv6 Explained'' at http://www.feyrer.de/NetBSD/6to4.html, NetBSD IPv6 Documentation at http://www.netbsd.org/Documentation/network/ipv6/, RFC 3068. HISTORY
The ip6config 6to4 utility and manpage portions were written by Hubert Feyrer <hubert@feyrer.de> for NetBSD. BSD
May 21, 2002 BSD