Merge pull request #95187 from twosigma/addingfailscenario

Adding failure scenario for long FQDN and setHostnameAsFQDN feature
This commit is contained in:
Kubernetes Prow Robot 2020-11-05 08:28:53 -08:00 committed by GitHub
commit eca53507be
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2 changed files with 100 additions and 11 deletions

View File

@ -163,6 +163,7 @@ go_test(
"//pkg/kubelet/cm/cpuset:go_default_library",
"//pkg/kubelet/cm/topologymanager:go_default_library",
"//pkg/kubelet/container:go_default_library",
"//pkg/kubelet/events:go_default_library",
"//pkg/kubelet/eviction:go_default_library",
"//pkg/kubelet/eviction/api:go_default_library",
"//pkg/kubelet/images:go_default_library",
@ -201,6 +202,7 @@ go_test(
"//staging/src/k8s.io/mount-utils:go_default_library",
"//test/e2e/common:go_default_library",
"//test/e2e/framework:go_default_library",
"//test/e2e/framework/events:go_default_library",
"//test/e2e/framework/gpu:go_default_library",
"//test/e2e/framework/kubectl:go_default_library",
"//test/e2e/framework/manifest:go_default_library",

View File

@ -24,10 +24,16 @@ import (
"crypto/rand"
"fmt"
"math/big"
"time"
v1 "k8s.io/api/core/v1"
metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
"k8s.io/apimachinery/pkg/fields"
"k8s.io/kubernetes/pkg/kubelet/events"
"k8s.io/kubernetes/test/e2e/framework"
e2eevents "k8s.io/kubernetes/test/e2e/framework/events"
e2epod "k8s.io/kubernetes/test/e2e/framework/pod"
imageutils "k8s.io/kubernetes/test/utils/image"
"github.com/onsi/ginkgo"
@ -41,8 +47,8 @@ func generatePodName(base string) string {
return fmt.Sprintf("%s-%d", base, id)
}
func testPod() *v1.Pod {
podName := generatePodName("hostfqdn")
func testPod(podnamebase string) *v1.Pod {
podName := generatePodName(podnamebase)
pod := &v1.Pod{
ObjectMeta: metav1.ObjectMeta{
Name: podName,
@ -65,6 +71,10 @@ func testPod() *v1.Pod {
var _ = SIGDescribe("Hostname of Pod [Feature:SetHostnameAsFQDN][NodeAlphaFeature:SetHostnameAsFQDN]", func() {
f := framework.NewDefaultFramework("hostfqdn")
dnsDomain := "cluster.local"
if cdn := framework.TestContext.ClusterDNSDomain; cdn != "" {
dnsDomain = cdn
}
/*
Release: v1.19
@ -72,11 +82,11 @@ var _ = SIGDescribe("Hostname of Pod [Feature:SetHostnameAsFQDN][NodeAlphaFeatur
Description: A Pod that does not define the subdomain field in it spec, does not have FQDN.
*/
ginkgo.It("a pod without subdomain field does not have FQDN", func() {
pod := testPod()
pod := testPod("hostfqdn")
pod.Spec.Containers[0].Command = []string{"sh", "-c", "echo $(hostname)';'$(hostname -f)';'"}
output := []string{fmt.Sprintf("%s;%s;", pod.ObjectMeta.Name, pod.ObjectMeta.Name)}
// Create Pod
f.TestContainerOutput("shotname only", pod, 0, output)
f.TestContainerOutput("shortname only", pod, 0, output)
})
/*
@ -86,14 +96,14 @@ var _ = SIGDescribe("Hostname of Pod [Feature:SetHostnameAsFQDN][NodeAlphaFeatur
Hence, SetHostnameAsFQDN feature has no effect.
*/
ginkgo.It("a pod without FQDN is not affected by SetHostnameAsFQDN field", func() {
pod := testPod()
pod := testPod("hostfqdn")
// Setting setHostnameAsFQDN field to true should have no effect.
setHostnameAsFQDN := true
pod.Spec.SetHostnameAsFQDN = &setHostnameAsFQDN
pod.Spec.Containers[0].Command = []string{"sh", "-c", "echo $(hostname)';'$(hostname -f)';'"}
output := []string{fmt.Sprintf("%s;%s;", pod.ObjectMeta.Name, pod.ObjectMeta.Name)}
// Create Pod
f.TestContainerOutput("shotname only", pod, 0, output)
f.TestContainerOutput("shortname only", pod, 0, output)
})
/*
@ -103,16 +113,16 @@ var _ = SIGDescribe("Hostname of Pod [Feature:SetHostnameAsFQDN][NodeAlphaFeatur
hostname command returns shortname (pod name in this case), and hostname -f returns FQDN.
*/
ginkgo.It("a pod with subdomain field has FQDN, hostname is shortname", func() {
pod := testPod()
pod := testPod("hostfqdn")
pod.Spec.Containers[0].Command = []string{"sh", "-c", "echo $(hostname)';'$(hostname -f)';'"}
subdomain := "t"
// Set PodSpec subdomain field to generate FQDN for pod
pod.Spec.Subdomain = subdomain
// Expected Pod FQDN
hostFQDN := fmt.Sprintf("%s.%s.%s.svc.%s", pod.ObjectMeta.Name, subdomain, f.Namespace.Name, framework.TestContext.ClusterDNSDomain)
hostFQDN := fmt.Sprintf("%s.%s.%s.svc.%s", pod.ObjectMeta.Name, subdomain, f.Namespace.Name, dnsDomain)
output := []string{fmt.Sprintf("%s;%s;", pod.ObjectMeta.Name, hostFQDN)}
// Create Pod
f.TestContainerOutput("shotname and fqdn", pod, 0, output)
f.TestContainerOutput("shortname and fqdn", pod, 0, output)
})
/*
@ -122,7 +132,7 @@ var _ = SIGDescribe("Hostname of Pod [Feature:SetHostnameAsFQDN][NodeAlphaFeatur
hostname is set to be the FQDN. In this case, both commands hostname and hostname -f return the FQDN of the Pod.
*/
ginkgo.It("a pod with subdomain field has FQDN, when setHostnameAsFQDN is set to true, the FQDN is set as hostname", func() {
pod := testPod()
pod := testPod("hostfqdn")
pod.Spec.Containers[0].Command = []string{"sh", "-c", "echo $(hostname)';'$(hostname -f)';'"}
subdomain := "t"
// Set PodSpec subdomain field to generate FQDN for pod
@ -131,7 +141,7 @@ var _ = SIGDescribe("Hostname of Pod [Feature:SetHostnameAsFQDN][NodeAlphaFeatur
setHostnameAsFQDN := true
pod.Spec.SetHostnameAsFQDN = &setHostnameAsFQDN
// Expected Pod FQDN
hostFQDN := fmt.Sprintf("%s.%s.%s.svc.%s", pod.ObjectMeta.Name, subdomain, f.Namespace.Name, framework.TestContext.ClusterDNSDomain)
hostFQDN := fmt.Sprintf("%s.%s.%s.svc.%s", pod.ObjectMeta.Name, subdomain, f.Namespace.Name, dnsDomain)
// Fail if FQDN is longer than 64 characters, otherwise the Pod will remain pending until test timeout.
// In Linux, 64 characters is the limit of the hostname kernel field, which this test sets to the pod FQDN.
framework.ExpectEqual(len(hostFQDN) < 65, true, fmt.Sprintf("The FQDN of the Pod cannot be longer than 64 characters, requested %s which is %d characters long.", hostFQDN, len(hostFQDN)))
@ -140,4 +150,81 @@ var _ = SIGDescribe("Hostname of Pod [Feature:SetHostnameAsFQDN][NodeAlphaFeatur
f.TestContainerOutput("fqdn and fqdn", pod, 0, output)
})
/*
Release: v1.20
Testname: Fail to Create Pod with longer than 64 bytes FQDN when setHostnameAsFQDN field set to true.
Description: A Pod that defines the subdomain field in it spec has FQDN.
When setHostnameAsFQDN: true, the hostname is set to be
the FQDN. Since kernel limit is 64 bytes for hostname field,
if pod FQDN is longer than 64 bytes it will generate events
regarding FailedCreatePodSandBox.
*/
ginkgo.It("a pod configured to set FQDN as hostname will remain in Pending "+
"state generating FailedCreatePodSandBox events when the FQDN is "+
"longer than 64 bytes", func() {
// 55 characters for name plus -<int>.t.svc.cluster.local is way more than 64 bytes
pod := testPod("hostfqdnveryveryveryverylongforfqdntobemorethan64bytes")
pod.Spec.Containers[0].Command = []string{"sh", "-c", "echo $(hostname)';'$(hostname -f)';'"}
subdomain := "t"
// Set PodSpec subdomain field to generate FQDN for pod
pod.Spec.Subdomain = subdomain
// Set PodSpec setHostnameAsFQDN to set FQDN as hostname
setHostnameAsFQDN := true
pod.Spec.SetHostnameAsFQDN = &setHostnameAsFQDN
// Create Pod
launchedPod := f.PodClient().Create(pod)
// Ensure we delete pod
defer f.PodClient().DeleteSync(launchedPod.Name, metav1.DeleteOptions{}, framework.DefaultPodDeletionTimeout)
// Pod should remain in the pending state generating events with reason FailedCreatePodSandBox
// Expected Message Error Event
expectedMessage := "Failed to create pod sandbox: failed " +
"to construct FQDN from pod hostname and cluster domain, FQDN "
framework.Logf("Waiting for Pod to generate FailedCreatePodSandBox event.")
// Wait for event with reason FailedCreatePodSandBox
expectSandboxFailureEvent(f, launchedPod, expectedMessage)
// Check Pod is in Pending Phase
err := checkPodIsPending(f, launchedPod.ObjectMeta.Name, launchedPod.ObjectMeta.Namespace)
framework.ExpectNoError(err)
})
})
// expectSandboxFailureEvent polls for an event with reason "FailedCreatePodSandBox" containing the
// expected message string.
func expectSandboxFailureEvent(f *framework.Framework, pod *v1.Pod, msg string) {
eventSelector := fields.Set{
"involvedObject.kind": "Pod",
"involvedObject.name": pod.Name,
"involvedObject.namespace": f.Namespace.Name,
"reason": events.FailedCreatePodSandBox,
}.AsSelector().String()
framework.ExpectNoError(e2eevents.WaitTimeoutForEvent(
f.ClientSet, f.Namespace.Name, eventSelector, msg, framework.PodEventTimeout))
}
func checkPodIsPending(f *framework.Framework, podName, namespace string) error {
c := f.ClientSet
// we call this functoin after we saw event failing to create Pod, hence
// pod has already been created and it should be in Pending status. Giving
// 30 seconds to fetch the pod to avoid failing for transient issues getting
// pods.
fetchPodTimeout := 30 * time.Second
return e2epod.WaitForPodCondition(c, namespace, podName, "Failed to Create Pod", fetchPodTimeout, func(pod *v1.Pod) (bool, error) {
// We are looking for the pod to be scheduled and in Pending state
if pod.Status.Phase == v1.PodPending {
for _, cond := range pod.Status.Conditions {
if cond.Type == v1.PodScheduled && cond.Status == v1.ConditionTrue {
return true, nil
}
}
}
// If pod gets to this status, either FQDN is shorter than 64bytes
// or setHostnameAsFQDN feature is not enable/in use.
if pod.Status.Phase == v1.PodRunning || pod.Status.Phase == v1.PodSucceeded || pod.Status.Phase == v1.PodFailed {
return true, fmt.Errorf("Expected pod %q in namespace %q to be in phase Pending, but got phase: %v", podName, namespace, pod.Status.Phase)
}
return false, nil
})
}