Package: ifupdown Version: 0.8.11 Severity: normal Tags: ipv6 Hi,
I'm trying to configure a tap-device using a inet6 static stanza, but it ends up unusable: /etc/network/interfaces: ---------------8<--------------------- iface tap1 inet6 static dad-attempts 0 privext 2 pre-up tunctl -t $IFACE; ip addr flush dev $IFACE address fd00:1::/128 post-down tunctl -d $IFACE -------------->8---------------------- Turns out, after an `ifup tap1`, the v6 address shows up as tentative, even though dad-attempts is set to 0: ---------------8<--------------------- # ifup --verbose tap1 Configuring interface tap1=tap1 (inet6) tunctl -t $IFACE; ip addr flush dev $IFACE Set 'tap1' persistent and owned by uid 0 /bin/run-parts --exit-on-error --verbose /etc/network/if-pre-up.d run-parts: executing /etc/network/if-pre-up.d/bridge run-parts: executing /etc/network/if-pre-up.d/ethtool run-parts: executing /etc/network/if-pre-up.d/uml-utilities /sbin/modprobe -q net-pf-10 > /dev/null 2>&1 || true # ignore failure. /sbin/sysctl -q -e -w net.ipv6.conf.tap1.use_tempaddr=2 /sbin/sysctl -q -e -w net.ipv6.conf.tap1.autoconf=0 /bin/ip link set dev tap1 up /bin/ip -6 addr add fd00:1::/128 dev tap1 /bin/run-parts --exit-on-error --verbose /etc/network/if-up.d run-parts: executing /etc/network/if-up.d/addresses run-parts: executing /etc/network/if-up.d/ethtool run-parts: executing /etc/network/if-up.d/mountnfs run-parts: executing /etc/network/if-up.d/nslcd Sending network state change signal to nslcd...done. run-parts: executing /etc/network/if-up.d/openssh-server run-parts: executing /etc/network/if-up.d/proxy-setup run-parts: executing /etc/network/if-up.d/uml-utilities run-parts: executing /etc/network/if-up.d/upstart # ip addr list dev tap1 15: tap1: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast state DOWN group default qlen 1000 link/ether 3a:de:89:d6:47:15 brd ff:ff:ff:ff:ff:ff inet6 fd00:1::/128 scope global tentative <-------------------- valid_lft forever preferred_lft forever # ping6 -c1 fd00:1:: PING fd00:1::(fd00:1::) 56 data bytes >From fd00:4818::216:3eff:fe00:36 icmp_seq=1 Destination unreachable: Address unreachable --- fd00:1:: ping statistics --- 1 packets transmitted, 0 received, +1 errors, 100% packet loss, time 0ms -------------->8---------------------- Doing the same thing in a "manual" stanza and calling `ip -6 addr add` with the nodad confflag set, another tap device ends up in a usable state: /etc/network/interfaces: ---------------8<--------------------- iface tap3 inet6 manual dad-attempts 0 privext 2 pre-up tunctl -t $IFACE; ip addr flush dev $IFACE post-up ip -6 addr add dev $IFACE fd00:3::/128 nodad post-down tunctl -d $IFACE -------------->8---------------------- ---------------8<--------------------- # ifup --verbose tap3 Configuring interface tap3=tap3 (inet6) tunctl -t $IFACE; ip addr flush dev $IFACE Set 'tap3' persistent and owned by uid 0 /bin/run-parts --exit-on-error --verbose /etc/network/if-pre-up.d run-parts: executing /etc/network/if-pre-up.d/bridge run-parts: executing /etc/network/if-pre-up.d/ethtool run-parts: executing /etc/network/if-pre-up.d/uml-utilities /bin/ip link set dev tap3 up 2>/dev/null || true ip -6 addr add dev $IFACE fd00:3::/128 nodad /bin/run-parts --exit-on-error --verbose /etc/network/if-up.d run-parts: executing /etc/network/if-up.d/addresses run-parts: executing /etc/network/if-up.d/ethtool run-parts: executing /etc/network/if-up.d/mountnfs run-parts: executing /etc/network/if-up.d/nslcd Sending network state change signal to nslcd...done. run-parts: executing /etc/network/if-up.d/openssh-server run-parts: executing /etc/network/if-up.d/proxy-setup run-parts: executing /etc/network/if-up.d/uml-utilities run-parts: executing /etc/network/if-up.d/upstart # ip addr list dev tap3 16: tap3: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast state DOWN group default qlen 1000 link/ether ea:90:c4:b2:12:a4 brd ff:ff:ff:ff:ff:ff inet6 fd00:3::/128 scope global nodad valid_lft forever preferred_lft forever /# ping6 -c1 fd00:3:: PING fd00:3::(fd00:3::) 56 data bytes 64 bytes from fd00:3::: icmp_seq=1 ttl=64 time=0.028 ms --- fd00:3:: ping statistics --- 1 packets transmitted, 1 received, 0% packet loss, time 0ms rtt min/avg/max/mdev = 0.028/0.028/0.028/0.000 ms -------------->8---------------------- Thanks Dnaiel -- System Information: Debian Release: stretch/sid APT prefers unstable APT policy: (990, 'unstable'), (500, 'stable') Architecture: amd64 (x86_64) Kernel: Linux 4.5.0-2-amd64 (SMP w/6 CPU cores) Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8) Shell: /bin/sh linked to /bin/bash Init: sysvinit (via /sbin/init) Versions of packages ifupdown depends on: ii adduser 3.114 ii init-system-helpers 1.33 ii iproute2 4.3.0-1+b1 ii libc6 2.22-9 ii lsb-base 9.20160110 Versions of packages ifupdown recommends: ii isc-dhcp-client [dhcp-client] 4.3.4-1 Versions of packages ifupdown suggests: ii ppp 2.4.7-1+2 pn rdnssd <none> -- no debconf information