rdnssd(8) [debian man page]
RDNSSD(8) System Manager's Manual RDNSSD(8) NAME
rdnssd - IPv6 Recursive DNS Server discovery Daemon SYNOPSIS
rdnssd [-f] [-H merge-hook] [-r resolv-file] [-p pidfile] [-u username] DESCRIPTON
rdnssd is a daemon program providing client-side support for DNS configuration using the Recursive DNS Server (RDNSS) option, as described in RFC 5006. Its purpose is to supply IPv6 DNS resolvers through stateless autoconfiguration, carried by Router Advertisements. rdnssd parses RDNSS options and keeps track of resolvers to write nameservers entries to a resolv.conf(5) configuration file. By default, it writes its own separate file, and may call an external hook to merge it with the main /etc/resolv.conf. This is aimed at easing coexis- tence with concurrent daemons, especially IPv4 ones, updating /etc/resolv.conf too. On Linux, since version 2.6.24, rdnssd takes advantage of a new netlink interface, forwarding RDNSS options validated by the kernel to userland. Otherwise, it merely listens to all ICMPv6 traffic through a raw socket. OPTIONS
-f or --foreground Do not detach from the console. Run the program in the foreground. -H merge-hook or --merge-hook merge-hook Execute this hook whenever resolv.conf is updated. If this option is not specified, then no hook will be called. -h or --help Display some help and exit. -p pidfile or --pidfile pidfile Override the location of the pidfile. -r resolv-file or --resolv-file resolv-file Set the path to the generated resolv.conf file. -u username or --user username Override the user that the program will run as. By default, it runs as nobody. -V or --version Display program version and license and exit. FILES
/etc/rdnssd/merge-hook A basic merge hook shipped with rdnssd, to be called with the -H option. /var/run/rdnssd/resolv.conf The default resolv.conf(5) file that rdnssd writes its configuration to. /var/run/rdnssd.pid The process-id file. BUGS
rdnssd does not keep track of the lifetimes of the routers associated with some DNS resolvers, whereas it should to strictly comply with RFC 5006. When rdnssd uses a raw socket instead of the netlink kernel interface, it does not validate received Neighbor Discovery traffic in any way. For example, it will always consider Router Advertisement packets, whereas it should not if the host is configured as a router. When the netlink interface is used, such validation is done by the kernel. SEE ALSO
resolv.conf(5), rdisc6(8), ipv6(7) AUTHOR
Pierre Ynard <linkfanel at yahoo.fr> $Id: rdnssd.8-in 575 2007-12-29 21:55:43Z linkfanel $ http://www.remlab.net/ndisc6/ rdnssd $Date: 2007-12-29 23:55:43 +0200 (Sat, 29 Dec 2007) $ RDNSSD(8)
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RESOLVCONF(8) System Manager's Manual RESOLVCONF(8) NAME
resolvconf -- a framework for managing multiple DNS configurations SYNOPSIS
resolvconf -I resolvconf [-m metric] [-p] -a interface <file resolvconf [-f] -d interface resolvconf -il pattern resolvconf -u DESCRIPTION
resolvconf manages resolv.conf(5) files from multiple sources, such as DHCP and VPN clients. Traditionally, the host runs just one client and that updates /etc/resolv.conf. More modern systems frequently have wired and wireless interfaces and there is no guarantee both are on the same network. With the advent of VPN and other types of networking daemons, many things now contend for the contents of /etc/resolv.conf. resolvconf solves this by letting the daemon send their resolv.conf(5) file to resolvconf via stdin(3) with the argument -a interface instead of the filesystem. resolvconf then updates /etc/resolv.conf as it thinks best. When a local resolver other than libc is installed, such as dnsmasq(8) or named(8), then resolvconf will supply files that the resolver should be configured to include. resolvconf can mark an interfaces resolv.conf as private. This means that the name servers listed in that resolv.conf are only used for queries against the domain/search listed in the same file. This only works when a local resolver other than libc is installed. See resolvconf.conf(5) for how to configure resolvconf to use a local name server. When an interface goes down, it should then call resolvconf with -d interface arguments to delete the resolv.conf file for the interface. Here are some more options that resolvconf has:- -I Initialise the state directory /var/run/resolvconf. This only needs to be called if the initial system boot sequence does not auto- matically clean it out; for example the state directory is moved somewhere other than /var/run. If used, it should only be called once as early in the system boot sequence as possible and before resolvconf is used to add interfaces. -f Ignore non existant interfaces. Only really useful for deleting interfaces. -i pattern List the interfaces, optionally matching pattern, we have resolv.conf files for. -l pattern List the resolv.conf files we have. If pattern is specified then we list the files for the interfaces that match it. -m metric Set the metric of the interface when adding it, default of 0. Lower metrics take precedence. This affects the default order of interfaces when listed. -p Marks the interface resolv.conf as private. -u Force resolvconf to update all it's subscribers. resolvconf does not update the subscribers when adding a resolv.conf that matches what it already has for that interface. resolvconf also has some options designed to be used by it's subscribers:- -v Echo variables DOMAINS, SEARCH and NAMESERVERS so that the subscriber can configure the resolver easily. INTERFACE ORDERING
For resolvconf to work effectively, it has to process the resolv.confs for the interfaces in the correct order. resolvconf first processes interfaces from the interface_order list, then interfaces without a metic and that match the dynamic_order list, then interfaces with a met- ric in order and finally the rest in the operating systems lexical order. See resolvconf.conf(5) for details on these lists. IMPLEMENTATION NOTES
If a subscriber has the executable bit then it is executed otherwise it is assumed to be a shell script and sourced into the current environ- ment in a subshell. This is done so that subscribers can remain fast, but are also not limited to the shell language. Portable subscribers should not use anything outside of /bin and /sbin because /usr and others may not be available when booting. Also, it would be unwise to assume any shell specific features. ENVIRONMENT
IF_METRIC If the -m option is not present then we use IF_METRIC for the metric. IF_PRIVATE Marks the interface resolv.conf as private. FILES
/etc/resolvconf.conf Configuration file for resolvconf. /libexec/resolvconf Directory of subscribers which are run every time resolvconf adds, deletes or updates. /libexec/resolvconf/libc.d Directory of subscribers which are run after the libc subscriber is run. /var/run/resolvconf State directory for resolvconf. HISTORY
This implementation of resolvconf is called openresolv and is fully command line compatible with Debian's resolvconf, as written by Thomas Hood. SEE ALSO
resolv.conf(5), resolvconf.conf(5), resolver(3), stdin(3) AUTHORS
Roy Marples <roy@marples.name> BUGS
Please report them to http://roy.marples.name/projects/openresolv resolvconf does not validate any of the files given to it. When running a local resolver other than libc, you will need to configure it to include files that resolvconf will generate. You should con- sult resolvconf.conf(5) for instructions on how to configure your resolver. BSD
May 13, 2011 BSD