1. Please describe the problem: After few days of running kernel-5.0.x my IPv6 connectivity gets very unreliable and kernel log is full of: neighbour: arp_cache: neighbor table overflow 2. What is the Version-Release number of the kernel: kernel-5.0.6-200.fc29.x86_64 fails kernel-5.0.11-200.fc29.x86_64 fails 3. Did it work previously in Fedora? If so, what kernel version did the issue *first* appear? Old kernels are available for download at https://koji.fedoraproject.org/koji/packageinfo?packageID=8 : kernel-4.20.16-200.fc29.x86_64 works fine 4. Can you reproduce this issue? If so, please provide the steps to reproduce the issue below: Yes, run IPv6 on local gigabit ethernet over openvpn and ping it, sometimes it stops responding: 17:24:08.288597 IP6 fc00::67:2 > fc00::67:1: ICMP6, echo request, seq 717, length 1408 17:24:08.288632 IP6 fc00::67:1 > fc00::67:2: ICMP6, echo reply, seq 717, length 1408 17:24:08.298252 IP6 fc00::67:2 > fc00::67:1: ICMP6, echo request, seq 718, length 1408 17:24:08.298287 IP6 fc00::67:1 > fc00::67:2: ICMP6, echo reply, seq 718, length 1408 17:24:08.308274 IP6 fc00::67:2 > fc00::67:1: ICMP6, echo request, seq 719, length 1408 17:24:08.319391 IP6 fc00::67:2 > fc00::67:1: ICMP6, echo request, seq 720, length 1408 5. Does this problem occur with the latest Rawhide kernel? To install the Rawhide kernel, run ``sudo dnf install fedora-repos-rawhide`` followed by ``sudo dnf update --enablerepo=rawhide kernel``: Latest Rawhide is kernel-5.1.0-1.fc31 and it still does not contain the fix so I expect it will still fail but I have not verified that. 6. Are you running any modules that not shipped with directly Fedora's kernel?: No. 7. Please attach the kernel logs. You can get the complete kernel log for a boot with ``journalctl --no-hostname -k > dmesg.txt``. If the issue occurred on a previous boot, use the journalctl ``-b`` flag. May 10 17:42:04 host1 kernel: neighbour: ndisc_cache: neighbor table overflow! May 10 17:42:04 host1 kernel: neighbour: ndisc_cache: neighbor table overflow! May 10 17:42:04 host1 kernel: neighbour: ndisc_cache: neighbor table overflow! May 10 17:42:04 host1 named[3391702]: ../../../../lib/isc/unix/socket.c:2173: unexpected error: May 10 17:42:04 host1 named[3391702]: internal_send: 2001:500:c::1#53: Invalid argument May 10 17:42:04 host1 kernel: net_ratelimit: 14 callbacks suppressed May 10 17:42:04 host1 kernel: neighbour: ndisc_cache: neighbor table overflow! Fix is: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=64c6f4bbca748c3b2101469a76d88b7cd1c00476
I get a similar error running Fedora 29: kernel-5.0.16-200.fc29.x86_64 bind-chroot-9.11.6-2.P1.fc29.x86_64 dhcp-server-4.3.6-31.fc29.x86_64 MAC and IP addresses are replaced by XXX and YYY: Mai 18 20:34:16 kernel: neighbour: arp_cache: neighbor table overflow! Mai 18 20:34:16 kernel: neighbour: arp_cache: neighbor table overflow! Mai 18 20:34:16 kernel: neighbour: arp_cache: neighbor table overflow! Mai 18 20:34:16 named[1367]: ../../../../lib/isc/unix/socket.c:2176: unexpected error: Mai 18 20:34:16 kernel: neighbour: arp_cache: neighbor table overflow! Mai 18 20:34:16 named[1367]: internal_send: YYY#59267: Invalid argument Mai 18 20:34:16 named[1367]: client @0xXXX YYY#59267 (fedoraproject.org): view ims: error sending response: invalid file Mai 18 20:34:16 named[1367]: ../../../../lib/isc/unix/socket.c:2176: unexpected error: Mai 18 20:34:16 named[1367]: internal_send: YYY#43658: Invalid argument It seams that the patch linked in previous comment is still not in released kernel? Is there a workaround for this problem (beside restarting the server very often)?
Created attachment 1570674 [details] kernel.spec patch to build F-29 kernel (In reply to Edgar Hoch from comment #1) > It seams that the patch linked in previous comment is still not in released > kernel? It is present in (not in 5.1.x): kernel-5.2.0-0.rc0.git6.1.fc31 = cbd87613cc306a7ccd5ce4006daf8dc737922c3f = has IPv6 But fc31 kernels are not installable into F-29 OS. They are installable into F-30 OS (but upgrade F-29 to F-30 failed for me due to LUKS today). > Is there a workaround for this problem (beside restarting the server very > often)? I build my own F-29 kernels with this attached patch.
The problem still affects also: kernel-5.0.19-200.fc29.x86_64
Also affected: 5.1.5-300.fc30.x86_64 On my server/router the problem manifests 3 to 4 days after reboot.
FWIW, also affected: 5.1.6-300.fc30.x86_64
And also affected kernel-5.1.7-200.fc29.x86_64 :-)
FEDORA-2019-c03eda3cc6 has been submitted as an update to Fedora 30. https://bodhi.fedoraproject.org/updates/FEDORA-2019-c03eda3cc6
FEDORA-2019-83858fc57b has been submitted as an update to Fedora 29. https://bodhi.fedoraproject.org/updates/FEDORA-2019-83858fc57b
kernel-5.1.8-300.fc30, kernel-headers-5.1.8-300.fc30 has been pushed to the Fedora 30 testing repository. If problems still persist, please make note of it in this bug report. See https://fedoraproject.org/wiki/QA:Updates_Testing for instructions on how to install test updates. You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2019-c03eda3cc6
kernel-5.1.8-200.fc29, kernel-headers-5.1.8-200.fc29 has been pushed to the Fedora 29 testing repository. If problems still persist, please make note of it in this bug report. See https://fedoraproject.org/wiki/QA:Updates_Testing for instructions on how to install test updates. You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2019-83858fc57b
kernel-5.1.8-300.fc30, kernel-headers-5.1.8-300.fc30 has been pushed to the Fedora 30 stable repository. If problems still persist, please make note of it in this bug report.
kernel-5.1.8-200.fc29, kernel-headers-5.1.8-200.fc29 has been pushed to the Fedora 29 stable repository. If problems still persist, please make note of it in this bug report.