microk8s cannot load br_netfilter modules on fedora 35 with kernel 5.16.18

[davidnich]

Please run microk8s inspect and attach the generated tarball to this issue. We appreciate your feedback. Thank you for using microk8s.

from snap.microk8s.daemon-kubelite/journal.log:

Apr 10 08:21:45 hq.qoretechnologies.com microk8s.daemon-kubelite[41091]: + modprobe br_netfilter
Apr 10 08:21:45 hq.qoretechnologies.com microk8s.daemon-kubelite[41210]: modprobe: symbol lookup error: /snap/core18/current/lib/x86_64-linux-gnu/libpthread.so.0: undefined symbol: __libc_vfork, version GLIBC_PRIVATE

inspection-report-20220410_083044.tar.gz

this results in some pods not starting:

$ kubectl get pods -n kube-system
NAME                                         READY   STATUS             RESTARTS         AGE
calico-node-gjp4n                            1/1     Running            0                21m
calico-node-525ck                            1/1     Running            0                21m
coredns-64c6478b6c-pzvxz                     0/1     Running            1 (8m36s ago)    24m
dashboard-metrics-scraper-69d9497b54-sd4mj   1/1     Running            1 (8m36s ago)    24m
calico-node-jt226                            1/1     Running            1 (8m36s ago)    21m
kubernetes-dashboard-585bdb5648-2q6q7        0/1     CrashLoopBackOff   12 (2m31s ago)   24m
calico-kube-controllers-5444d67ccf-8v4bf     0/1     CrashLoopBackOff   22 (95s ago)     31m
metrics-server-679c5f986d-rcwc2              0/1     CrashLoopBackOff   15 (13s ago)     25m

[Compunctus]

Same thing on Ubuntu 21.10. Preloading br_netfilter does nothing. Packet from coredns netns can be traced to default/kubernetes rule in nat table, kube-proxy doesn't really log anything useful.

[stale[bot]]

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