Public bug reported: I use netplan together network manager. After a while my computer lost its default route for ipv6. When investigating with tcpdump on another client (raspberry pi) I found that my router sends an icmpv6 router advertisement message about every 8-10 minutes, but my computer only receives 30-50% of the router advertisement messages. The wifi connection is stable and has a reception strength of around 80%. A ping6 with 1000 messages works without any packet loss. If no router advertisement message is received after 1800 seconds, the ipv6 default route disappears. A second computer with intel wifi hardware that still runs with kernel 5.4.0-91-generic but uses a different wifi chipset has the same problems. I also tested the mainline kernels 5.15.11 and 5.16.0-rc7. Still the same behavior with the other kernels. I don't see any error message in syslog or dmesg while a packet is lost. If I exchange my wifi hardware to an ALFA Network AWUS036ACH, then all packets are received and the default route stays stable.
######################################################## > sysctl net.ipv6.conf.wlp3s0 net.ipv6.conf.wlp3s0.accept_dad = 1 net.ipv6.conf.wlp3s0.accept_ra = 1 net.ipv6.conf.wlp3s0.accept_ra_defrtr = 1 net.ipv6.conf.wlp3s0.accept_ra_from_local = 0 net.ipv6.conf.wlp3s0.accept_ra_min_hop_limit = 1 net.ipv6.conf.wlp3s0.accept_ra_mtu = 1 net.ipv6.conf.wlp3s0.accept_ra_pinfo = 1 net.ipv6.conf.wlp3s0.accept_ra_rt_info_max_plen = 0 net.ipv6.conf.wlp3s0.accept_ra_rt_info_min_plen = 0 net.ipv6.conf.wlp3s0.accept_ra_rtr_pref = 1 net.ipv6.conf.wlp3s0.accept_redirects = 1 net.ipv6.conf.wlp3s0.accept_source_route = 0 net.ipv6.conf.wlp3s0.addr_gen_mode = 0 net.ipv6.conf.wlp3s0.autoconf = 1 net.ipv6.conf.wlp3s0.dad_transmits = 1 net.ipv6.conf.wlp3s0.disable_ipv6 = 0 net.ipv6.conf.wlp3s0.disable_policy = 0 net.ipv6.conf.wlp3s0.drop_unicast_in_l2_multicast = 0 net.ipv6.conf.wlp3s0.drop_unsolicited_na = 0 net.ipv6.conf.wlp3s0.enhanced_dad = 1 net.ipv6.conf.wlp3s0.force_mld_version = 0 net.ipv6.conf.wlp3s0.force_tllao = 0 net.ipv6.conf.wlp3s0.forwarding = 0 net.ipv6.conf.wlp3s0.hop_limit = 255 net.ipv6.conf.wlp3s0.ignore_routes_with_linkdown = 0 net.ipv6.conf.wlp3s0.keep_addr_on_down = 0 net.ipv6.conf.wlp3s0.max_addresses = 16 net.ipv6.conf.wlp3s0.max_desync_factor = 600 net.ipv6.conf.wlp3s0.mc_forwarding = 0 net.ipv6.conf.wlp3s0.mldv1_unsolicited_report_interval = 10000 net.ipv6.conf.wlp3s0.mldv2_unsolicited_report_interval = 1000 net.ipv6.conf.wlp3s0.mtu = 1492 net.ipv6.conf.wlp3s0.ndisc_notify = 0 net.ipv6.conf.wlp3s0.ndisc_tclass = 0 net.ipv6.conf.wlp3s0.proxy_ndp = 0 net.ipv6.conf.wlp3s0.regen_max_retry = 3 net.ipv6.conf.wlp3s0.router_probe_interval = 60 net.ipv6.conf.wlp3s0.router_solicitation_delay = 1 net.ipv6.conf.wlp3s0.router_solicitation_interval = 4 net.ipv6.conf.wlp3s0.router_solicitation_max_interval = 3600 net.ipv6.conf.wlp3s0.router_solicitations = -1 net.ipv6.conf.wlp3s0.rpl_seg_enabled = 0 net.ipv6.conf.wlp3s0.seg6_enabled = 0 net.ipv6.conf.wlp3s0.seg6_require_hmac = 0 sysctl: Zugriff verweigert auf Schlüssel »net.ipv6.conf.wlp3s0.stable_secret« net.ipv6.conf.wlp3s0.suppress_frag_ndisc = 1 net.ipv6.conf.wlp3s0.temp_prefered_lft = 86400 net.ipv6.conf.wlp3s0.temp_valid_lft = 604800 net.ipv6.conf.wlp3s0.use_oif_addrs_only = 0 net.ipv6.conf.wlp3s0.use_tempaddr = 1 ################################################################# A lost packet recorded on another client (raspberry pi) with > tcpdump -n -vv -i wlan0 icmp6 and 'ip6[40] = 134' 22:03:52.766917 IP6 (flowlabel 0x236ab, hlim 255, next-header ICMPv6 (58) payload length: 144) fe80::464e:6dff:fe42:d85d > ff02::1: [icmp6 sum ok] ICMP6, router advertisement, length 144 hop limit 255, Flags [managed, other stateful], pref high, router lifetime 1800s, reachable time 0ms, retrans timer 0ms prefix info option (3), length 32 (4): 2003:d1:bf19:600::/64, Flags [onlink, auto], valid time 7200s, pref. time 1800s 0x0000: 40c0 0000 1c20 0000 0708 0000 0000 2003 0x0010: 00d1 bf19 0600 0000 0000 0000 0000 prefix info option (3), length 32 (4): fd05:7501:b88f::/64, Flags [onlink, auto], valid time 0s, pref. time 0s 0x0000: 40c0 0000 0000 0000 0000 0000 0000 fd05 0x0010: 7501 b88f 0000 0000 0000 0000 0000 rdnss option (25), length 24 (3): lifetime 1200s, addr: fe80::c0ff:7ee3:779b:6b31 0x0000: 0000 0000 04b0 fe80 0000 0000 0000 c0ff 0x0010: 7ee3 779b 6b31 mtu option (5), length 8 (1): 1492 0x0000: 0000 0000 05d4 route info option (24), length 8 (1): ::/0, pref=high, lifetime=1800s 0x0000: 0008 0000 0708 route info option (24), length 16 (2): 2003:d1:bf19:600::/56, pref=high, lifetime=1800s 0x0000: 3808 0000 0708 2003 00d1 bf19 0600 source link-address option (1), length 8 (1): 44:4e:6d:42:d8:5d 0x0000: 444e 6d42 d85d ################################################################### Routing with default route > ip -6 route show dev wlp3s0 2003:d1:bf19:600::/64 proto kernel metric 256 expires 6948sec pref medium fe80::/64 proto kernel metric 256 pref medium default via fe80::464e:6dff:fe42:d85d proto ra metric 1024 expires 1548sec mtu 1492 hoplimit 255 pref high ################################################################### Routing without default route >ip -6 route show dev wlp3s0 2003:d1:bf19:600::/64 proto kernel metric 256 expires 5382sec pref medium fe80::/64 proto kernel metric 256 pref medium ProblemType: Bug DistroRelease: Ubuntu 20.04 Package: linux-image-5.11.0-43-generic 5.11.0-43.47~20.04.2 ProcVersionSignature: Ubuntu 5.11.0-43.47~20.04.2-generic 5.11.22 Uname: Linux 5.11.0-43-generic x86_64 ApportVersion: 2.20.11-0ubuntu27.21 Architecture: amd64 CasperMD5CheckResult: skip CurrentDesktop: KDE Date: Thu Dec 30 20:52:55 2021 InstallationDate: Installed on 2020-05-01 (608 days ago) InstallationMedia: Kubuntu 20.04 LTS "Focal Fossa" - Release amd64 (20200423) SourcePackage: linux-signed-hwe-5.11 UpgradeStatus: No upgrade log present (probably fresh install) ** Affects: linux-signed-hwe-5.11 (Ubuntu) Importance: Undecided Status: New ** Tags: amd64 focal kernel-wifi -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux-signed-hwe-5.11 in Ubuntu. https://bugs.launchpad.net/bugs/1956066 Title: iwlwifi driver losts icmpv6 router advertisement packages Status in linux-signed-hwe-5.11 package in Ubuntu: New Bug description: I use netplan together network manager. After a while my computer lost its default route for ipv6. When investigating with tcpdump on another client (raspberry pi) I found that my router sends an icmpv6 router advertisement message about every 8-10 minutes, but my computer only receives 30-50% of the router advertisement messages. The wifi connection is stable and has a reception strength of around 80%. A ping6 with 1000 messages works without any packet loss. If no router advertisement message is received after 1800 seconds, the ipv6 default route disappears. A second computer with intel wifi hardware that still runs with kernel 5.4.0-91-generic but uses a different wifi chipset has the same problems. I also tested the mainline kernels 5.15.11 and 5.16.0-rc7. Still the same behavior with the other kernels. I don't see any error message in syslog or dmesg while a packet is lost. If I exchange my wifi hardware to an ALFA Network AWUS036ACH, then all packets are received and the default route stays stable. ######################################################## > sysctl net.ipv6.conf.wlp3s0 net.ipv6.conf.wlp3s0.accept_dad = 1 net.ipv6.conf.wlp3s0.accept_ra = 1 net.ipv6.conf.wlp3s0.accept_ra_defrtr = 1 net.ipv6.conf.wlp3s0.accept_ra_from_local = 0 net.ipv6.conf.wlp3s0.accept_ra_min_hop_limit = 1 net.ipv6.conf.wlp3s0.accept_ra_mtu = 1 net.ipv6.conf.wlp3s0.accept_ra_pinfo = 1 net.ipv6.conf.wlp3s0.accept_ra_rt_info_max_plen = 0 net.ipv6.conf.wlp3s0.accept_ra_rt_info_min_plen = 0 net.ipv6.conf.wlp3s0.accept_ra_rtr_pref = 1 net.ipv6.conf.wlp3s0.accept_redirects = 1 net.ipv6.conf.wlp3s0.accept_source_route = 0 net.ipv6.conf.wlp3s0.addr_gen_mode = 0 net.ipv6.conf.wlp3s0.autoconf = 1 net.ipv6.conf.wlp3s0.dad_transmits = 1 net.ipv6.conf.wlp3s0.disable_ipv6 = 0 net.ipv6.conf.wlp3s0.disable_policy = 0 net.ipv6.conf.wlp3s0.drop_unicast_in_l2_multicast = 0 net.ipv6.conf.wlp3s0.drop_unsolicited_na = 0 net.ipv6.conf.wlp3s0.enhanced_dad = 1 net.ipv6.conf.wlp3s0.force_mld_version = 0 net.ipv6.conf.wlp3s0.force_tllao = 0 net.ipv6.conf.wlp3s0.forwarding = 0 net.ipv6.conf.wlp3s0.hop_limit = 255 net.ipv6.conf.wlp3s0.ignore_routes_with_linkdown = 0 net.ipv6.conf.wlp3s0.keep_addr_on_down = 0 net.ipv6.conf.wlp3s0.max_addresses = 16 net.ipv6.conf.wlp3s0.max_desync_factor = 600 net.ipv6.conf.wlp3s0.mc_forwarding = 0 net.ipv6.conf.wlp3s0.mldv1_unsolicited_report_interval = 10000 net.ipv6.conf.wlp3s0.mldv2_unsolicited_report_interval = 1000 net.ipv6.conf.wlp3s0.mtu = 1492 net.ipv6.conf.wlp3s0.ndisc_notify = 0 net.ipv6.conf.wlp3s0.ndisc_tclass = 0 net.ipv6.conf.wlp3s0.proxy_ndp = 0 net.ipv6.conf.wlp3s0.regen_max_retry = 3 net.ipv6.conf.wlp3s0.router_probe_interval = 60 net.ipv6.conf.wlp3s0.router_solicitation_delay = 1 net.ipv6.conf.wlp3s0.router_solicitation_interval = 4 net.ipv6.conf.wlp3s0.router_solicitation_max_interval = 3600 net.ipv6.conf.wlp3s0.router_solicitations = -1 net.ipv6.conf.wlp3s0.rpl_seg_enabled = 0 net.ipv6.conf.wlp3s0.seg6_enabled = 0 net.ipv6.conf.wlp3s0.seg6_require_hmac = 0 sysctl: Zugriff verweigert auf Schlüssel »net.ipv6.conf.wlp3s0.stable_secret« net.ipv6.conf.wlp3s0.suppress_frag_ndisc = 1 net.ipv6.conf.wlp3s0.temp_prefered_lft = 86400 net.ipv6.conf.wlp3s0.temp_valid_lft = 604800 net.ipv6.conf.wlp3s0.use_oif_addrs_only = 0 net.ipv6.conf.wlp3s0.use_tempaddr = 1 ################################################################# A lost packet recorded on another client (raspberry pi) with > tcpdump -n -vv -i wlan0 icmp6 and 'ip6[40] = 134' 22:03:52.766917 IP6 (flowlabel 0x236ab, hlim 255, next-header ICMPv6 (58) payload length: 144) fe80::464e:6dff:fe42:d85d > ff02::1: [icmp6 sum ok] ICMP6, router advertisement, length 144 hop limit 255, Flags [managed, other stateful], pref high, router lifetime 1800s, reachable time 0ms, retrans timer 0ms prefix info option (3), length 32 (4): 2003:d1:bf19:600::/64, Flags [onlink, auto], valid time 7200s, pref. time 1800s 0x0000: 40c0 0000 1c20 0000 0708 0000 0000 2003 0x0010: 00d1 bf19 0600 0000 0000 0000 0000 prefix info option (3), length 32 (4): fd05:7501:b88f::/64, Flags [onlink, auto], valid time 0s, pref. time 0s 0x0000: 40c0 0000 0000 0000 0000 0000 0000 fd05 0x0010: 7501 b88f 0000 0000 0000 0000 0000 rdnss option (25), length 24 (3): lifetime 1200s, addr: fe80::c0ff:7ee3:779b:6b31 0x0000: 0000 0000 04b0 fe80 0000 0000 0000 c0ff 0x0010: 7ee3 779b 6b31 mtu option (5), length 8 (1): 1492 0x0000: 0000 0000 05d4 route info option (24), length 8 (1): ::/0, pref=high, lifetime=1800s 0x0000: 0008 0000 0708 route info option (24), length 16 (2): 2003:d1:bf19:600::/56, pref=high, lifetime=1800s 0x0000: 3808 0000 0708 2003 00d1 bf19 0600 source link-address option (1), length 8 (1): 44:4e:6d:42:d8:5d 0x0000: 444e 6d42 d85d ################################################################### Routing with default route > ip -6 route show dev wlp3s0 2003:d1:bf19:600::/64 proto kernel metric 256 expires 6948sec pref medium fe80::/64 proto kernel metric 256 pref medium default via fe80::464e:6dff:fe42:d85d proto ra metric 1024 expires 1548sec mtu 1492 hoplimit 255 pref high ################################################################### Routing without default route >ip -6 route show dev wlp3s0 2003:d1:bf19:600::/64 proto kernel metric 256 expires 5382sec pref medium fe80::/64 proto kernel metric 256 pref medium ProblemType: Bug DistroRelease: Ubuntu 20.04 Package: linux-image-5.11.0-43-generic 5.11.0-43.47~20.04.2 ProcVersionSignature: Ubuntu 5.11.0-43.47~20.04.2-generic 5.11.22 Uname: Linux 5.11.0-43-generic x86_64 ApportVersion: 2.20.11-0ubuntu27.21 Architecture: amd64 CasperMD5CheckResult: skip CurrentDesktop: KDE Date: Thu Dec 30 20:52:55 2021 InstallationDate: Installed on 2020-05-01 (608 days ago) InstallationMedia: Kubuntu 20.04 LTS "Focal Fossa" - Release amd64 (20200423) SourcePackage: linux-signed-hwe-5.11 UpgradeStatus: No upgrade log present (probably fresh install) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux-signed-hwe-5.11/+bug/1956066/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp