I use asus rt-n66u router with ipv6 turned on using 6to4 tunnel. It uses dhcp6s to send ipv6 DNS configuration to clients. On my desktop with gentoo amd64 dhcpcd makes my resolve.conf file correctly writing both ipv4 and ipv6 NS-servers to it. net-misc/dhcp-4.2.5_p1 USE="client ipv6 vim-syntax" If I use config like: modules="dhclient" config_enp5s3="dhcp" then I get only ipv4 NS-server from router in resolv.conf, this output: * Bringing up interface enp5s3 * dhcp ... * Running dhclient ... [ ok ] * received address 10.1.1.2/24 [ ok ] * Waiting for IPv6 addresses ... and these lines in log: Aug 11 19:51:32 localhost kernel: IPv6: ADDRCONF(NETDEV_UP): enp5s3: link is not ready Aug 11 19:51:33 localhost dhclient: DHCPREQUEST on enp5s3 to 255.255.255.255 port 67 Aug 11 19:51:37 localhost kernel: r8169 0000:05:03.0 enp5s3: link up Aug 11 19:51:37 localhost kernel: IPv6: ADDRCONF(NETDEV_CHANGE): enp5s3: link becomes ready Aug 11 19:51:37 localhost dhclient: DHCPREQUEST on enp5s3 to 255.255.255.255 port 67 Aug 11 19:51:37 localhost dhclient: DHCPACK from 10.1.1.1 Aug 11 19:51:37 localhost dhclient: bound to 10.1.1.2 -- renewal in 41717 seconds. If I use config like: modules="dhclient" config_enp5s3="dhcp" dhclient_enp5s3="-6" It stucks for a while after * Bringing up interface enp5s3 * dhcp ... * Running dhclient ... then * start-stop-daemon: failed to start `/sbin/dhclient' [ !! ] * ERROR: net.enp5s3 failed to start and in logs: Aug 11 19:53:33 localhost kernel: IPv6: ADDRCONF(NETDEV_UP): enp5s3: link is not ready Aug 11 19:53:33 localhost dhclient: Bound to *:546 Aug 11 19:53:34 localhost dhclient: XMT: Solicit on enp5s3, interval 1020ms. Aug 11 19:53:34 localhost dhclient: send_packet6: Network is unreachable Aug 11 19:53:34 localhost dhclient: dhc6: send_packet6() sent -1 of 52 bytes Aug 11 19:53:35 localhost dhclient: XMT: Solicit on enp5s3, interval 1980ms. Aug 11 19:53:35 localhost dhclient: send_packet6: Network is unreachable Aug 11 19:53:35 localhost dhclient: dhc6: send_packet6() sent -1 of 52 bytes Aug 11 19:53:37 localhost kernel: r8169 0000:05:03.0 enp5s3: link up Aug 11 19:53:37 localhost kernel: IPv6: ADDRCONF(NETDEV_CHANGE): enp5s3: link becomes ready Aug 11 19:53:37 localhost dhclient: XMT: Solicit on enp5s3, interval 4010ms. Aug 11 19:53:37 localhost dhclient: send_packet6: Cannot assign requested address Aug 11 19:53:37 localhost dhclient: dhc6: send_packet6() sent -1 of 52 bytes Aug 11 19:53:41 localhost dhclient: XMT: Solicit on enp5s3, interval 8350ms. Aug 11 19:53:41 localhost dhclient: RCV: Advertise message on enp5s3 from fe80::5246:5dff:fe00:77e8. Aug 11 19:53:41 localhost dhclient: message status code NoAddrsAvail. Aug 11 19:53:50 localhost dhclient: XMT: Solicit on enp5s3, interval 17190ms. Aug 11 19:53:50 localhost dhclient: RCV: Advertise message on enp5s3 from fe80::5246:5dff:fe00:77e8. Aug 11 19:53:50 localhost dhclient: message status code NoAddrsAvail. Aug 11 19:54:07 localhost dhclient: XMT: Solicit on enp5s3, interval 44620ms. Aug 11 19:54:07 localhost dhclient: RCV: Advertise message on enp5s3 from fe80::5246:5dff:fe00:77e8. Aug 11 19:54:07 localhost dhclient: message status code NoAddrsAvail. emerge --info Portage 2.1.12.2 (default/linux/amd64/13.0/desktop/kde, gcc-4.6.3, glibc-2.15-r3, 3.8.13-gentoo x86_64) ================================================================= System uname: Linux-3.8.13-gentoo-x86_64-Intel-R-_Core-TM-2_Quad_CPU_Q9505_@_2.83GHz-with-gentoo-2.2 KiB Mem: 8172260 total, 122036 free KiB Swap: 16777212 total, 16776644 free Timestamp of tree: Sun, 11 Aug 2013 06:45:01 +0000 ld GNU ld (GNU Binutils) 2.23.1 ccache version 3.1.9 [enabled] app-shells/bash: 4.2_p45 dev-java/java-config: 2.1.12-r1 dev-lang/python: 2.7.5, 3.2.5-r1 dev-util/ccache: 3.1.9 dev-util/pkgconfig: 0.28 sys-apps/baselayout: 2.2 sys-apps/openrc: 0.11.8 sys-apps/sandbox: 2.6-r1 sys-devel/binutils: 2.23.1 sys-devel/gcc: 4.6.3 sys-devel/gcc-config: 1.7.3 sys-devel/libtool: 2.4-r1 sys-devel/make: 3.82-r4 sys-kernel/linux-headers: 3.7 (virtual/os-headers) sys-libs/glibc: 2.15-r3 Repositories: gentoo steam-overlay x-unklay ACCEPT_KEYWORDS="amd64" ACCEPT_LICENSE="* -@EULA AdobeFlash-11.x Q3AEULA PUEL LOKI-EULA skype-4.0.0.7-copyright" CBUILD="x86_64-pc-linux-gnu" CFLAGS="-march=native -O2 -pipe" CHOST="x86_64-pc-linux-gnu" CONFIG_PROTECT="/etc /usr/share/config /usr/share/gnupg/qualified.txt /usr/share/themes/oxygen-gtk/gtk-2.0 /usr/share/vlc/lua/http/.hosts" CONFIG_PROTECT_MASK="/etc/ca-certificates.conf /etc/env.d /etc/fonts/fonts.conf /etc/gconf /etc/gentoo-release /etc/php/apache2-php5.4/ext-active/ /etc/php/cgi-php5.4/ext-active/ /etc/php/cli-php5.4/ext-active/ /etc/revdep-rebuild /etc/sandbox.d /etc/terminfo" CXXFLAGS="-march=native -O2 -pipe" DISTDIR="/home/portage/distfiles" FCFLAGS="-O2 -pipe" FEATURES="assume-digests binpkg-logs buildpkg ccache config-protect-if-modified distlocks ebuild-locks fixlafiles merge-sync news parallel-fetch preserve-libs protect-owned sandbox sfperms strict unknown-features-warn unmerge-logs unmerge-orphans userfetch userpriv usersandbox usersync" FFLAGS="-O2 -pipe" GENTOO_MIRRORS="ftp://gentoo.bloodhost.ru/ ftp://mirror.yandex.ru/gentoo-distfiles/" LANG="en_US.UTF-8" LDFLAGS="-Wl,-O1 -Wl,--as-needed" MAKEOPTS="-j5" PKGDIR="/home/portage/packages" PORTAGE_CONFIGROOT="/" PORTAGE_RSYNC_OPTS="--recursive --links --safe-links --perms --times --compress --force --whole-file --delete --stats --human-readable --timeout=180 --exclude=/distfiles --exclude=/local --exclude=/packages" PORTAGE_TMPDIR="/var/tmp" PORTDIR="/usr/portage" PORTDIR_OVERLAY="/var/lib/layman/steam /var/lib/layman/unklay" USE="X a52 aac acl acpi akonadi alsa amd64 amr audiofile bash-completion branding bzip2 cairo cdda cddb cdio cdparanoia cdr cli consolekit cracklib crypt css cups curl cxx dbus declarative device-mapper djvu dri dts dv dvd dvdr emboss encode exif ffmpeg firefox flac fontconfig fortran ftp gd geoip gif gimp gmp gnutls gphoto2 gpm graphviz gsm gstreamer gtk handbook iconv icu id3tag idn imagemagick imap imlib ios iphone ipod ipv6 jabber jbig jingle jpeg jpeg2k kde kipi kontact ladspa lame lcms libass libnotify libsamplerate libwww lm_sensors lzma lzo mac mad matroska mikmod mjpeg mmx mng modplug modules mp3 mp4 mpeg mplayer mudflap multilib musepack musicbrainz ncurses nls nptl ntfs ogg openal openexr opengl openmp pam pango pcre pdf phonon plasma png policykit ppds pulseaudio qt3support qt4 quicktime rar raw rdesktop readline rss rtmp sasl scanner schroedinger sdl semantic-desktop session sharedext smp sndfile socks5 speex spell sqlite sse sse2 sse3 sse4 ssl ssse3 startup-notification steamruntime svg symlink syslog taglib theora threads thumbnail tiff truetype udev udisks unicode upower usb vaapi video vim-syntax vlc vorbis wavpack webkit wmf wxwidgets x264 xcb xcomposite xface xml xmp xpm xscreensaver xv xvid zip zlib" ABI_X86="64" ALSA_CARDS="ali5451 als4000 atiixp atiixp-modem bt87x ca0106 cmipci emu10k1x ens1370 ens1371 es1938 es1968 fm801 hda-intel intel8x0 intel8x0m maestro3 trident usb-audio via82xx via82xx-modem ymfpci" APACHE2_MODULES="authn_core authz_core socache_shmcb unixd actions alias auth_basic authn_alias authn_anon authn_dbm authn_default authn_file authz_dbm authz_default authz_groupfile authz_host authz_owner authz_user autoindex cache cgi cgid dav dav_fs dav_lock deflate dir disk_cache env expires ext_filter file_cache filter headers include info log_config logio mem_cache mime mime_magic negotiation rewrite setenvif speling status unique_id userdir usertrack vhost_alias" CALLIGRA_FEATURES="kexi words flow plan sheets stage tables krita karbon braindump author" CAMERAS="ptp2" COLLECTD_PLUGINS="df interface irq load memory rrdtool swap syslog" DRACUT_MODULES="caps lvm" ELIBC="glibc" GPSD_PROTOCOLS="ashtech aivdm earthmate evermore fv18 garmin garmintxt gpsclock itrax mtk3301 nmea ntrip navcom oceanserver oldstyle oncore rtcm104v2 rtcm104v3 sirf superstar2 timing tsip tripmate tnt ubx" INPUT_DEVICES="evdev wacom" KERNEL="linux" LCD_DEVICES="bayrad cfontz cfontz633 glk hd44780 lb216 lcdm001 mtxorb ncurses text" LIBREOFFICE_EXTENSIONS="presenter-console presenter-minimizer pdfimport wiki-publisher" LINGUAS="ru en ru_RU" NGINX_MODULES_HTTP="access auth_basic autoindex browser charset empty_gif fastcgi geo gzip limit_req map referer rewrite split_clients spdy userid" OFFICE_IMPLEMENTATION="libreoffice" PHP_TARGETS="php5-4" PYTHON_SINGLE_TARGET="python2_7" PYTHON_TARGETS="python2_7" QEMU_SOFTMMU_TARGETS="x86_64 i386" QEMU_USER_TARGETS="x86_64 i386" RUBY_TARGETS="ruby19 ruby18" SANE_BACKENDS="plustek" USERLAND="GNU" VIDEO_CARDS="radeon fglrx" XTABLES_ADDONS="quota2 psd pknock lscan length2 ipv4options ipset ipp2p iface geoip fuzzy condition tee tarpit sysrq steal rawnat logmark ipmark dhcpmac delude chaos account" Unset: CPPFLAGS, CTARGET, EMERGE_DEFAULT_OPTS, INSTALL_MASK, LC_ALL, PORTAGE_BUNZIP2_COMMAND, PORTAGE_COMPRESS, PORTAGE_COMPRESS_FLAGS, PORTAGE_RSYNC_EXTRA_OPTS, USE_PYTHON
