Make the kubelet hostPort feature usable by default

[matrohon]

Is this a BUG REPORT or FEATURE REQUEST? (choose one): FEATURE REQUEST

Please provide the following details:

Environment: Debian stretch

Minikube version (use minikube version): v0.28.0

• OS (e.g. from /etc/os-release): Debian GNU/Linux 9 (stretch)
• VM Driver (e.g. cat ~/.minikube/machines/minikube/config.json | grep DriverName): kvm2
• ISO version (e.g. cat ~/.minikube/machines/minikube/config.json | grep -i ISO or minikube ssh cat /etc/VERSION):
• Install tools: v0.28.0
• Others:

What happened:
I'm enabling cni plugins for minikube by using the following command:
minikube start --vm-driver kvm2 --network-plugin=cni --extra-config=kubelet.network-plugin=cni --extra-config=kubelet.cni-conf-dir=/etc/cni/net.d --extra-config=kubelet.cni-bin-dir=/opt/cni/bin

I then want to use a pod with a hostPort, to access the pod easily from inside and outside the minikube VM.
Unfortunatly, the default cni conf file doesn't enable the "portmap" cni plugin, which enable the hostport feature.
So by default, when using cni plugins, a pod can't be accessed through a hostPort, even if it is configured.

What you expected to happen: I expect the hostPort feature to work by default.

Anything else do we need to know:

Since the portmap cni plugin is available in the minikube VM, at /opt/cni/bin, having the hostport feature enabled by default is just a matter of cni configuration file.

I removed the default /etc/cni/net.d/k8s.conf and added the file /etc/cni/net.d/10-k8s-portmap.conflist with the following content:

{
    "cniVersion": "0.3.1",
    "name": "rkt.kubernetes.io",
    "plugins": [
        {
            "type": "bridge",
            "bridge": "mybridge",
            "mtu": 1460,
            "addIf": "true",
            "isGateway": true,
            "ipMasq": true,
            "ipam": {
                "type": "host-local",
                "subnet": "10.1.0.0/16",
                "gateway": "10.1.0.1",
                "routes": [
                    {
                        "dst": "0.0.0.0/0"
                    }
                ]
            }
        },
        {
            "type": "portmap",
            "capabilities": {"portMappings": true},
            "externalSetMarkChain": "KUBE-MARK-MASQ"
        }
    ]
}

After restarting kubelet, a pod with hostPort enabled is accessible through minikube_ip:hostport, as expected.

[fejta-bot]

Issues go stale after 90d of inactivity.
Mark the issue as fresh with /remove-lifecycle stale.
Stale issues rot after an additional 30d of inactivity and eventually close.

If this issue is safe to close now please do so with /close.

Send feedback to sig-testing, kubernetes/test-infra and/or fejta.
/lifecycle stale

[fejta-bot]

Stale issues rot after 30d of inactivity.
Mark the issue as fresh with /remove-lifecycle rotten.
Rotten issues close after an additional 30d of inactivity.

If this issue is safe to close now please do so with /close.

Send feedback to sig-testing, kubernetes/test-infra and/or fejta.
/lifecycle rotten

[fejta-bot]

Issues go stale after 90d of inactivity.
Mark the issue as fresh with /remove-lifecycle stale.
Stale issues rot after an additional 30d of inactivity and eventually close.

If this issue is safe to close now please do so with /close.

Send feedback to sig-testing, kubernetes/test-infra and/or fejta.
/lifecycle stale

[GrigorievNick]

I use latest minikube version: v1.0.1, with k8s 1.3.5
minikube start --vm-driver=kvm2 --network-plugin cni --kubernetes-version v1.13.5 .
I have same issue. I'am developer not devops, i'am enable cni plugin just for test how NetworkPolicy work.
And i waste 10 hour, before i understand why my kafka external acess stop work.
This is very confused, that if you enable 'cni' some feature stop work.

[fejta-bot]

Issues go stale after 90d of inactivity.
Mark the issue as fresh with /remove-lifecycle stale.
Stale issues rot after an additional 30d of inactivity and eventually close.

If this issue is safe to close now please do so with /close.

Send feedback to sig-testing, kubernetes/test-infra and/or fejta.
/lifecycle stale

[fejta-bot]

Stale issues rot after 30d of inactivity.
Mark the issue as fresh with /remove-lifecycle rotten.
Rotten issues close after an additional 30d of inactivity.

If this issue is safe to close now please do so with /close.

Send feedback to sig-testing, kubernetes/test-infra and/or fejta.
/lifecycle rotten

[tstromberg]

I believe this is still likely an issue - so PR's welcome. I don't know much about CNI, but this is where the file is apparently generated:

minikube/pkg/minikube/bootstrapper/kubeadm/default_cni.go

Line 23 in 01f399b

const defaultCNIConfig = `

[woodcockjosh]

/assign

[woodcockjosh]

@tstromberg before I go too deep perhaps someone can explain why the hostPort feature appears to work for the ingress plugin but not for any other pods? Some type of special nginx witchcraft?

[medyagh]

@woodcockjosh do you we still consider this ?

[medyagh]

@woodcockjosh are you still interested in doing this task ?

[medyagh]

this issue is free for anyone who is interested to pick it up