why the kubernetes pod shows Back-off restarting failed container [duplicate] - kubernetes

Question

This question already has answers here:
How can I keep a container running on Kubernetes?
(14 answers)
My kubernetes pods keep crashing with "CrashLoopBackOff" but I can't find any log
(21 answers)
Closed 2 years ago.
I want to build a troube shooting pod, this is my Dockerbuild file:
FROM alpine:3.11
MAINTAINER jiangxiaoqiang (jiangtingqiang#gmail.com)
ENV LANG=en_US.UTF-8 \
LC_ALL=en_US.UTF-8 \
TZ=Asia/Shanghai
RUN ln -snf /usr/share/zoneinfo/$TZ /etc/localtime \
&& echo $TZ > /etc/timezone \
&& apk add --no-cache curl jq \
nmap \
bind-tools \
busybox-extras \
bash
CMD ["/bin/bash","-l"]
but when I start it in kubernetes cluster, it shows: Back-off restarting failed container, and always restart all the time. so simple docker container ,why give me this tips? this is the descibe output:
[root#k8smaster ~]# kubectl describe pod ts-7d754488b9-jqqh9
Name: ts-7d754488b9-jqqh9
Namespace: default
Priority: 0
Node: k8sslave2/192.168.31.31
Start Time: Wed, 02 Sep 2020 12:28:48 -0400
Labels: k8s-app=ts
pod-template-hash=7d754488b9
Annotations: cni.projectcalico.org/podIP: 10.11.125.135/32
Status: Running
IP: 10.11.125.135
IPs:
IP: 10.11.125.135
Controlled By: ReplicaSet/ts-7d754488b9
Containers:
ts:
Container ID: docker://0c810ed8f8ec1cde6c0249edde59fc28a169d5730e87c423403f802cd12df6dd
Image: registry.cn-shanghai.aliyuncs.com/jiangxiaoqiang/dolphin/k8s-ts:v0.0.1
Image ID: docker-pullable://registry.cn-shanghai.aliyuncs.com/jiangxiaoqiang/dolphin/k8s-ts#sha256:68edaed45c1fadee71abbe7bdaad23f2400f352f1b6309142689a197367f3ae9
Port: <none>
Host Port: <none>
State: Waiting
Reason: CrashLoopBackOff
Last State: Terminated
Reason: Completed
Exit Code: 0
Started: Wed, 02 Sep 2020 12:30:13 -0400
Finished: Wed, 02 Sep 2020 12:30:13 -0400
Ready: False
Restart Count: 4
Environment: <none>
Mounts:
/var/run/secrets/kubernetes.io/serviceaccount from default-token-79w95 (ro)
Conditions:
Type Status
Initialized True
Ready False
ContainersReady False
PodScheduled True
Volumes:
default-token-79w95:
Type: Secret (a volume populated by a Secret)
SecretName: default-token-79w95
Optional: false
QoS Class: BestEffort
Node-Selectors: <none>
Tolerations: node.kubernetes.io/not-ready:NoExecute for 300s
node.kubernetes.io/unreachable:NoExecute for 300s
Events:
Type Reason Age From Message
---- ------ ---- ---- -------
Normal Scheduled <unknown> default-scheduler Successfully assigned default/ts-7d754488b9-jqqh9 to k8sslave2
Normal Created 96s (x4 over 2m17s) kubelet, k8sslave2 Created container ts
Normal Started 95s (x4 over 2m16s) kubelet, k8sslave2 Started container ts
Warning BackOff 69s (x7 over 2m15s) kubelet, k8sslave2 Back-off restarting failed container
Normal Pulling 54s (x5 over 2m17s) kubelet, k8sslave2 Pulling image "registry.cn-shanghai.aliyuncs.com/jiangxiaoqiang/dolphin/k8s-ts:v0.0.1"
Normal Pulled 54s (x5 over 2m17s) kubelet, k8sslave2 Successfully pulled image "registry.cn-shanghai.aliyuncs.com/jiangxiaoqiang/dolphin/k8s-ts:v0.0.1"

Answer 1

The container is completed means it is finished it's execution task. If you wish the container should run for specific time then pass eg . sleep 3600 as argument or you can use restartPolicy: Never in your deployment file.
something like this
spec:
containers:
- image: alpine
command:
- /bin/sh
- "-c"
- "sleep 60m"
imagePullPolicy: Always
restartPolicy: Never
name: alpine