1RDNSSD(8) System Manager's Manual RDNSSD(8)
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6 rdnssd - IPv6 Recursive DNS Server discovery Daemon
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9 rdnssd [-f] [-H merge-hook] [-r resolv-file] [-p pidfile] [-u username]
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13 rdnssd is a daemon program providing client-side support for DNS con‐
14 figuration using the Recursive DNS Server (RDNSS) option, as described
15 in RFC 5006. Its purpose is to supply IPv6 DNS resolvers through
16 stateless autoconfiguration, carried by Router Advertisements.
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18 rdnssd parses RDNSS options and keeps track of resolvers to write name‐
19 servers entries to a resolv.conf(5) configuration file. By default, it
20 writes its own separate file, and may call an external hook to merge it
21 with the main /etc/resolv.conf. This is aimed at easing coexistence
22 with concurrent daemons, especially IPv4 ones, updating
23 /etc/resolv.conf too.
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25 On Linux, since version 2.6.24, rdnssd takes advantage of a new netlink
26 interface, forwarding RDNSS options validated by the kernel to user‐
27 land. Otherwise, it merely listens to all ICMPv6 traffic through a raw
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32 -f or --foreground
33 Do not detach from the console. Run the program in the fore‐
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37 -H merge-hook or --merge-hook merge-hook
38 Execute this hook whenever resolv.conf is updated. If this
39 option is not specified, then no hook will be called.
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42 -h or --help
43 Display some help and exit.
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46 -p pidfile or --pidfile pidfile
47 Override the location of the pidfile.
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50 -r resolv-file or --resolv-file resolv-file
51 Set the path to the generated resolv.conf file.
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54 -u username or --user username
55 Override the user that the program will run as. By default, it
56 runs as nobody.
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59 -V or --version
60 Display program version and license and exit.
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64 /etc/rdnssd/merge-hook
65 A basic merge hook shipped with rdnssd, to be called with the -H
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69 /var/run/rdnssd/resolv.conf
70 The default resolv.conf(5) file that rdnssd writes its configu‐
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74 /var/run/rdnssd.pid
75 The process-id file.
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79 rdnssd does not keep track of the lifetimes of the routers associated
80 with some DNS resolvers, whereas it should to strictly comply with RFC
81 5006.
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83 When rdnssd uses a raw socket instead of the netlink kernel interface,
84 it does not validate received Neighbor Discovery traffic in any way.
85 For example, it will always consider Router Advertisement packets,
86 whereas it should not if the host is configured as a router. When the
87 netlink interface is used, such validation is done by the kernel.
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91 resolv.conf(5), rdisc6(8), ipv6(7)
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95 Pierre Ynard <linkfanel at yahoo.fr>
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97 http://www.remlab.net/ndisc6/
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101rdnssd $Date$ RDNSSD(8)