k8s network tool nsenter

k8s tools

Use the nsenter command to enter the container namespace for packet capture and network diagnosis

#!/bin/bash

ns=$1     #传参1：命名空间
pod_name=$2  #传参2：pod名称

Container_id=$(kubectl describe pod -n $ns $pod_name  | grep "Container ID:" | cut -d '/' -f 3 | cut -c 1-12)
node=$(kubectl get pods -n $ns $pod_name -o wide | awk '{print $7}' | grep -v NODE)
docker_id='docker_id1=$(docker inspect -f {
      
      {
      
      .State.Pid}}'
read -t 30 -p "是否建立远程连接确认y/n:" num1

if [ $num1 == y ];then
   echo "-----------------节点输入-----------------"
   echo "$docker_id $Container_id)"
         docker_id1="$docker_id $Container_id"
   echo 'nsenter -n --target $docker_id1'
   echo "------------------------------------------"
   read -t 30 -p "ssh连接用户名:" name
   ssh $name@$node
  else
   echo "-----------------节点输入-----------------"
   echo "$docker_id $Container_id)"
         docker_id1="$docker_id $Container_id"
   echo 'nsenter -n --target $docker_id1'
   echo "------------------------------------------"
fi

bash k8s_ns.sh kube-system coredns-7cccdb8747-qztnd
#执行脚本并传参

Script command analysis

View the container ID of the specified pod running

• kubectl describe pod -n mservice

Get the pid of the container process (enter the Pod node)

• docker inspect -f { {.State.Pid}}

Enter the network namespace of the container (enter the Pod node)

• nsenter -n --target