DNS resolvers are not requested/learned from DHCPv6
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
isc-dhcp (Ubuntu) |
Fix Released
|
Medium
|
Unassigned |
Bug Description
Binary package hint: network-manager
When attempting to connect to a DHCPv6-using network (after having set the IPv6 mode in the connection profile to "automatic"), DHCPv6 is successfully used to acquire and configure an IPv6 address, however at no point does the Ubuntu host request DNS servers from DHCPv6. This means that only IPv4 DHCPv4-provided name servers are being added, or if there's no IPv4 on the network, *no* name servers are being configured - the network connection is for all practical purposes unusable.
I reproduced this easily using the Ubuntu 11.04 Beta 2 64-bit desktop live-CD. I'll be attaching a PCAP dump containing the network traffic from when the network connection was established. You can see clearly that the ICMPv6 Router Advertisement (frame 16) has both the M and O flags set, but the DHCPv6 queries (frames 23 and 27) do not request neither DNS recursive name servers nor the domain search list. Essentially it behaves as if the O flag was unset. I'll also be attaching the content logged to /var/log/syslog during the network connection attempt.
Curiously enough, Fedora 14 (also using NetworkManager) has no problems connecting to the exact same network and discovering the DNS server using DHCPv6. I'll also attach a PCAP file containing the DHCPv6 traffic from that connection attempt, and it's clear that the DNS information is requested and received, and also shows up in /etc/resolv.conf in the end.
Tore
I'll tentatively confirm this, but for now I have no idea if it's really NM or if there's some difference in the DHCP clients we use vs. the one in Fedora (or just configuration, even).