Public bug reported: IMO this is not related to Kubernetes so I filed the bug here.
**What happened**: Processes in container can't connect to `kubernetes.default` service. **What you expected to happen**: It should be able to connect. **How to reproduce it (as minimally and precisely as possible)**: ```bash host# tc qdisc add dev eth0 root fq host# nsenter -n -t $(pidof some-process-in-container) container-net-ns# nc -vv 10.97.0.1 443 # Could not connect ``` **Anything else we need to know?**: ```bash host# tc qdisc add dev eth0 root noqueue # this works host# tc qdisc add dev eth0 root fq_codel # this works too ``` - `host` is where the workload container is, not Kubernetes master. - When the bug condition is met, packets won't be sent on wire. - kube-proxy works in IPVS mode. - The reason to tinker with qdisc is to enable TCP BBR, which requires fq qdisc. - fq qdisc works in `Linux node1 4.15.0-106-generic #107-Ubuntu SMP Thu Jun 4 11:27:52 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux (Ubuntu 18.04)` **Environment**: - Cloud provider or hardware configuration: `NIC: Intel X520-DA1 (82599)` - OS (e.g: `cat /etc/os-release`): `Ubuntu 20.04.1 LTS \n \l` - Kernel (e.g. `uname -a`): `Linux Proton 5.4.0-52-generic #57-Ubuntu SMP Thu Oct 15 10:57:00 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux` - Install tools: - Network plugin and version (if this is a network-related bug): `Calico v3.14.1 with IPIP & NAT-Outgoing` - Others: ** Affects: linux (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/1902358 Title: Kubernetes service connectivity issue Ubuntu 20.04 + fq queue discipline To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1902358/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs