Public bug reported: My ISP's router provides IPv6 connectivity and advertises valid lifetime of 900 secs and preferred lifetime of 300 secs. My Ubuntu 17.04 (and previous) installation has been showing weird behavior over IPv6, with connections dropping quite often but on a regular basis.
After extensive debugging and verification that there was no issue on router side, and on WiFi physical connection, I have verified that this was not related to the lack of ICMPv6 RA packets. Running |watch -d -n1 ip -6 addr show dev wlan0| shows: - decreasing valid_lft and preferred_lft on both IPv6 addresses - upon ICMPv6 RA packet received, the global SLAAC address derived from MAC gets valid_lft and preferred_lft field updated - at the same time, the privacy extension address is still decreasing System uses NetworkManager to handle all of that. I could verify that my desktop system, running Debian Sid with NetworkManager v1.6 was not exposing the issue. Running NetworkManager in debug mode gives more informations: > nm_ubuntu_zesty.log:NetworkManager[2418]: <trace> [1496447074.7897] > platform-linux: event-notification: NEWADDR, seq 0: > 2a01:XXXX:XXXX:XXXX:XXXX:XXXX:XXXX:39c5/64 lft 900sec pref 300sec lifetime > 289-289[300,900] dev 3 flags secondary src kernel > nm_ubuntu_zesty.log:NetworkManager[2418]: <trace> [1496447074.7901] > platform-linux: event-notification: NEWADDR, seq 0: > 2a01:XXXX:XXXX:XXXX:XXXX:XXXX:XXXX:39c5/64 lft 622sec pref 22sec lifetime > 289-289[22,622] dev 3 flags secondary src kernel The two timestamps of the NEWADDR event are very very close. The first one shows proper update of the lifetimes values ; while the second one shows invalid values being pushed. With those informations in mind, I dug a little bit in the NetworkManager source code, and I found that there was one change between v1.4.4 (current Zesty package) and v1.6 (Debian sid package) that was touching the code handling IPv6 addresses sync: https://cgit.freedesktop.org/NetworkManager/NetworkManager/commit/?id=1dbd9d7948 ; the commit states that without this change, NM might overwrite IPv6 temporary addresses changes. I took my chance and rebuilt network-manager-1.4.4 package with that patch included: IPv6 temporary privacy extensions enabled addresses gets proper updates of their lifetime when ICMPv6 packets reaches my system. ** Affects: network-manager (Ubuntu) Importance: Undecided Status: New -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1695601 Title: IPv6 temporary/privacy addresses lifetime are not renewed upon new ICMPv6 Router-Advertisement packet To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/network-manager/+bug/1695601/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs