K8S常用工具＜k8s_pod.sh＞ 一键脚本登录kubectl exec ＜pod＞

Posted 2021-06-27 江南飞羽

疼点:

繁琐：每次登录pod都要执行n条命令，kubectl get pod 获取pod名字，然后kubectl exec -it 登录pod

联系作者：如有疑问可评论区留言， 或加本人微信咨询q613230000， 请说明CSDN文章

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躺着运维:

备注：如通过一键脚本工具，解决了哪些问题

1）快速登录：bash pod.sh -p <pod_name> -e 即可快速登录pod，用于替代kubectl exec -it

2）常见问题排查：是否有僵尸进程、pod端口是否监听、到底有多少cpu_limit、node cpu多少

3)   一键输出史上最相信的pod配额, 你无需再各种命令，一次过打印明细给你。躺着运维

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目标：

开发一个一键脚本， 输出pod信息如：

1）配额：cpu_limit, ram_limit,

2）路径： 对应node上的存储路径, pod占用存储空间信息, 

3）Pod状态： used cpu, used ram , 以及其他信息 

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功能说明:

1) 参数说明

-e      一键登录等效kubectl exec -it <pod_name> -- /bin/bash

-p      输入pod_name , 无需输入nameSpace(自动匹配), 且只需输入pod_name关键字如dep2即可（完整pod_name dep2-647d655dfb-6bfvh）

2）命令示例 @一键登录 dep2 (pod_name)

bash pod.sh -p dep2 -e

 

3）命令示例 @查看pod明细信息 (cpu/ram) (path/container_id/其他)

bash pod.sh  -p dep2

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脚本代码

前言：ok上干货，效果图请看上文， 脚本源码如下

使用：将以下源码copy到本地，明明为pod.sh/k8s_pod.sh都可以，bash pod.sh -p <你的pod名字>即可运行

备注： 原创不易，兄弟路过可点个赞， 如有新需求可留言，下个版本迭代

#!/bin/bash
# how to use: this shell script is to lookup container merge dir via pod_name
# usage: sh k8s_pod.sh -p <pod_name>

#. /tmp/import_function.sh

script_name=$0

while getopts "p:i:e" INPUT_OPT; do
    case $INPUT_OPT in
        p)INPUT_POD_NAME=$OPTARG;;
        i)IS_LOOKUP_DOCKER_INSPECT=enable;;
        e)IS_LOGIN_CONTAINER_VIA_KUBECTL_EXEC=enable;;
    esac
done

format_1="%-25s%-55s\\n"
format_2="%-25s%-55.1f\\n"
format_3="%-25s%-10s%-25s\\n"

print_color_blue() {
    input_1="$*"; red=31; green=32; yellow=33; blue=34; white=37
    color=$blue
    printf "\\033[4;${color}m${input_1}\\033[0m\\n"
}

sum_help=1
print_function_name() {
    input_1=$1
    input_2=$2
    split_line="==================================="
    print_color_blue  "\\n""["${sum_help}"]"$input_1""
    sum_help=$((${sum_help}+1))
}

print_release_note() {
    print_function_name $FUNCNAME
    echo release_note: ::'6/12 v1.2 release for pod cpu/ram percentage lookup' | awk -F:: '{printf("'"$format_1"'",$1,$2)}'
}

print_usage() {
    print_function_name $FUNCNAME
    echo "
e.g:                     bash $script_name -p pod01            # pod short name, via cmd 'docker ps -a | grep <pod_short_name>'
e.g:                     bash $script_name -p pod01-xxx-yyy    # pod full namae
    " | sed "1d"
}


container_id_dir_cpuquota_ramquota_lookup() {
    # lookup id/path/cpu/ram via podname and docker inspect
    print_function_name $FUNCNAME
    pod_name=`kubectl get pod -A |grep $INPUT_POD_NAME |awk '{print $2}'`
    [ -z $pod_name ]  && echo "error:     pod name not exist , pls check:  kubectl get pod -o wide |grep $INPUT_POD_NAME" && exit 88
    pod_namespace=`kubectl get pod -A |grep $INPUT_POD_NAME |awk '{print $1}'`
    container_id=`docker ps -a |grep $INPUT_POD_NAME |grep -v '/pause' |grep -v 'Exited' |awk '{print $1}'`
    container_dir_merge=`docker inspect $container_id |grep merge |sed "s/ //g"`
    container_dir_merge_only_value=`docker inspect $container_id |grep merge |sed "s/ //g"|awk -F: '{print $2}' |sed "s/\\"//g; s/,//g"`
    container_inspect_info=`docker inspect $container_id`
    container_cpu_limit=`echo "$container_inspect_info" | cat -n |grep CpuQuota | awk -F: '{print $2}' |sed "s/,//g; s/ //g"`
    container_ram_limit=`echo "$container_inspect_info" | cat -n |grep '"Memory"' | awk -F: '{print $2}' |sed "s/,//g; s/ //g"`
    node_cpu_quota=`echo "$container_inspect_info" | cat -n |grep CpuPeriod | awk -F: '{print $2}' |sed "s/,//g; s/ //g"`
    # output like:  cpu/ram/node_cpu 50000=500m 1073741824=1Gi cpu=100000=1core
    echo pod_name: $pod_name | awk '{printf("'"$format_1"'",$1,$2)}'
    echo container_id: $container_id | awk '{printf("'"$format_1"'",$1,$2)}'
    echo container_disk_path: $container_dir_merge_only_value | awk '{printf("'"$format_1"'",$1,$2)}'
    # use awk -F:: as sperator
    echo container_cpu_limit: ::${container_cpu_limit} ::'(e.g: 500 = 0.5 cpu_core)' | awk -F'::' '{printf("'"$format_3"'",$1,$2/100,$3)}'  # cpu 50000=500m=0.5c
    echo container_ram_limit'(MB)': $container_ram_limit | awk '{printf("'"$format_1"'",$1,$2/1024/1024)}'  # ram 1073741824=1024MB
    echo node_cpu_quota: ::${node_cpu_quota} ::'(e.g: 4000 = 4 cpu_core)' | awk -F'::' '{printf("'"$format_3"'",$1,$2/100,$3)}'  # cpu 50000=500m=0.5c

}

container_cpu_mem_resource_lookup_via_id() {
    print_function_name $FUNCNAME
    container_pid=`ps aux |grep $container_id |grep -v grep |awk '{printf $2}'`
    container_cpu_pct=`ps aux |grep $container_id |grep -v grep |grep -v Exited |awk '{printf $3}'`
    container_mem_pct=`ps aux |grep $container_id |grep -v grep |grep -v Exited |awk '{printf $4}'`
    container_mem_vsz=`ps aux |grep $container_id |grep -v grep |awk '{printf $5}'`
    container_mem_rsz=`ps aux |grep $container_id |grep -v grep |awk '{printf $6}'`
    echo container_pid: $container_pid | awk '{printf("'"$format_1"'",$1,$2)}'
    echo container_cpu%: $container_cpu_pct | awk '{printf("'"$format_1"'",$1,$2)}'
    echo container_mem%: $container_mem_pct | awk '{printf("'"$format_1"'",$1,$2)}'
    echo container_mem_vsz'(MB)': $container_mem_vsz | awk '{printf("'"$format_2"'",$1,$2/1024)}'
    echo container_mem_rsz'(MB)': $container_mem_rsz | awk '{printf("'"$format_2"'",$1,$2/1024)}'
}

node_cpu_mem_resource_lookup_via_shell() {
    print_function_name $FUNCNAME
    cpu_core=`lscpu |egrep '^CPU.s.:' |awk '{print $2}'`
    cpu_load=`uptime |awk '{print $(NF-2),$(NF-1),$NF}'|sed "s/ /\\//g"|sed "s/,//g"`
    process_status=`ps aux --no-header |awk '{a[$8]++} END{for(i in a) print i,a[i]}'|sort -k2n|sed "s/ /_/g"|tr "\\n" "/"`
    tcp_socket_count=`ss -tn |grep -v State |cat -n|wc -l`
    ram_total=`free -m|grep Mem:|awk '{print $2}'`
    ram_free=`free -m|grep Mem:|awk '{print $4}'`
    ram_free_available=`free -m|grep Mem:|awk '{print $NF}'`
    ram_free_available_total=`echo $ram_free $ram_free_available $ram_total | sed "s/ /\\//g"`  # sed combine free/available/total
    echo cpu_core: $cpu_core | awk '{printf("'"$format_1"'",$1,$2)}'
    echo cpu_load: $cpu_load | awk '{printf("'"$format_1"'",$1,$2)}'
    echo process_status: $process_status | awk '{printf("'"$format_1"'",$1,$2)}'
    echo tcp_socket_count: $tcp_socket_count | awk '{printf("'"$format_1"'",$1,$2)}'
    echo ram_total'(MB)': $ram_total | awk '{printf("'"$format_1"'",$1,$2)}'
    echo ram_free'(MB)': $ram_free | awk '{printf("'"$format_1"'",$1,$2)}'
    echo ram_free_available'(MB)': $ram_free_available | awk '{printf("'"$format_1"'",$1,$2)}'
    echo ram_free_avail_total: $ram_free_available_total | awk '{printf("'"$format_1"'",$1,$2)}'
}

container_inside_process_and_socket_info() {
    print_function_name $FUNCNAME
    echo -e "--------------------ps aux--------------------"
    kubectl -n $pod_namespace exec -it $pod_name -- ps aux
    echo -e "--------------------netstat -tunlp--------------------"
    kubectl -n $pod_namespace exec -it $pod_name -- netstat -tunlp
}

login_container_via_kubectl_exec() {
    # need pod_name arg from function container_id_dir_lookup_via_podname
    print_function_name $FUNCNAME
    echo -e "login container successfully: $pod_name \\n"
    echo -e "please type exit if you want to exit container \\n\\n"
    kubectl -n $pod_namespace exec -it $pod_name -- /bin/bash || kubectl -n $pod_namespace exec -it $pod_name -- /bin/sh
}

lookup_docker_inspect_info() {
    print_function_name $FUNCNAME
    docker inspect $container_id
}

#print_release_note
print_usage
container_id_dir_cpuquota_ramquota_lookup
container_cpu_mem_resource_lookup_via_id
node_cpu_mem_resource_lookup_via_shell
container_inside_process_and_socket_info
[ "$IS_LOOKUP_DOCKER_INSPECT" == "enable" ] && lookup_docker_inspect_info
[ "$IS_LOGIN_CONTAINER_VIA_KUBECTL_EXEC" == "enable" ] && login_container_via_kubectl_exec
echo -e "\\n\\n"