[#]: collector: (lujun9972) [#]: translator: (geekpi) [#]: reviewer: ( ) [#]: publisher: ( ) [#]: url: ( ) [#]: subject: (Scan Kubernetes for errors with KRAWL) [#]: via: (https://opensource.com/article/20/2/kubernetes-scanner) [#]: author: (Abhishek Tamrakar https://opensource.com/users/tamrakar) 使用 KRAWL 扫描 Kubernetes 错误 ====== 用 KRAWL 脚本来标识 Kubernetes pod 和容器中的错误。 ![Ship captain sailing the Kubernetes seas][1] 当你使用 Kubernetes 运行容器时，你通常会发现它们堆积。这是设计使然。它是容器的优点之一：每当需要新的容器时，它们启动成本都很低。你可以使用前端（如 OpenShift 或 OKD）来管理 pod 和容器。这些工具使可视化设置变得容易，并且它具有一组丰富的用于快速交互的命令。 如果管理容器的平台不符合你的要求，你也可以仅使用 Kubernetes 工具链获取这些信息，但这需要大量命令才能全面了解复杂环境。出于这个原因，我编写了 [KRAWL][2]，这是一个简单的脚本，可用于扫描 Kubernetes 集群命名空间下的 pod 和容器，并在发现任何事件时，显示事件的输出。它也可用作为 Kubernetes 插件使用。这是获取大量有用信息的快速简便方法。 ### 预先条件 * 必须安装 kubectl。 * 集群的 kubeconfig 配置必须在它的默认位置 （$HOME/.kube/config） 或已被导出。 ### 使用 ``` `$ ./krawl` ``` ![KRAWL script][3] ### 脚本 ``` #!/bin/bash # AUTHOR: Abhishek Tamrakar # EMAIL: [abhishek.tamrakar08@gmail.com][4] # LICENSE: Copyright (C) 2018 Abhishek Tamrakar # #  Licensed under the Apache License, Version 2.0 (the "License"); #  you may not use this file except in compliance with the License. #  You may obtain a copy of the License at # #       # #   Unless required by applicable law or agreed to in writing, software #   distributed under the License is distributed on an "AS IS" BASIS, #   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. #   See the License for the specific language governing permissions and #   limitations under the License. ## #define the variables KUBE_LOC=~/.kube/config #define variables KUBECTL=$(which kubectl) GET=$(which egrep) AWK=$(which awk) red=$(tput setaf 1) normal=$(tput sgr0) # define functions # wrapper for printing info messages info() {   printf '\n\e[34m%s\e[m: %s\n' "INFO" "$@" } # cleanup when all done cleanup() {   rm -f results.csv } # just check if the command we are about to call is available checkcmd() {   #check if command exists   local cmd=$1   if [ -z "${!cmd}" ]   then     printf '\n\e[31m%s\e[m: %s\n' "ERROR"  "check if $1 is installed !!!"     exit 1   fi } get_namespaces() {   #get namespaces   namespaces=( \           $($KUBECTL get namespaces --ignore-not-found=true | \           $AWK '/Active/ {print $1}' \           ORS=" ") \           ) #exit if namespaces are not found if [ ${#namespaces[@]} -eq 0 ] then   printf '\n\e[31m%s\e[m: %s\n' "ERROR"  "No namespaces found!!"   exit 1 fi } #get events for pods in errored state get_pod_events() {   printf '\n'   if [ ${#ERRORED[@]} -ne 0 ]   then       info "${#ERRORED[@]} errored pods found."       for CULPRIT in ${ERRORED[@]}       do         info "POD: $CULPRIT"         info         $KUBECTL get events \         --field-selector=involvedObject.name=$CULPRIT \         -ocustom-columns=LASTSEEN:.lastTimestamp,REASON:.reason,MESSAGE:.message \         --all-namespaces \         --ignore-not-found=true       done   else       info "0 pods with errored events found."   fi } #define the logic get_pod_errors() {   printf "%s %s %s\n" "NAMESPACE,POD_NAME,CONTAINER_NAME,ERRORS" > results.csv   printf "%s %s %s\n" "---------,--------,--------------,------" >> results.csv   for NAMESPACE in ${namespaces[@]}   do     while IFS=' ' read -r POD CONTAINERS     do       for CONTAINER in ${CONTAINERS//,/ }       do         COUNT=$($KUBECTL logs --since=1h --tail=20 $POD -c $CONTAINER -n $NAMESPACE 2>/dev/null| \         $GET -c '^error|Error|ERROR|Warn|WARN')         if [ $COUNT -gt 0 ]         then             STATE=("${STATE[@]}" "$NAMESPACE,$POD,$CONTAINER,$COUNT")         else         #catch pods in errored state             ERRORED=($($KUBECTL get pods -n $NAMESPACE --no-headers=true | \                 awk '!/Running/ {print $1}' ORS=" ") \                 )         fi       done     done< <($KUBECTL get pods -n $NAMESPACE --ignore-not-found=true -o=custom-columns=NAME:.metadata.name,CONTAINERS:.spec.containers[*].name --no-headers=true)   done   printf "%s\n" ${STATE[@]:-None} >> results.csv   STATE=() } #define usage for seprate run usage() { cat << EOF   USAGE: "${0##*/} </path/to/kube-config>(optional)"   This program is a free software under the terms of Apache 2.0 License.   COPYRIGHT (C) 2018 Abhishek Tamrakar EOF exit 0 } #check if basic commands are found trap cleanup EXIT checkcmd KUBECTL # #set the ground if [ $# -lt 1 ]; then   if [ ! -e ${KUBE_LOC} -a ! -s ${KUBE_LOC} ]   then     info "A readable kube config location is required!!"     usage   fi elif [ $# -eq 1 ] then   export KUBECONFIG=$1 elif [ $# -gt 1 ] then   usage fi #play get_namespaces get_pod_errors printf '\n%40s\n' 'KRAWL' printf '%s\n' '---------------------------------------------------------------------------------' printf '%s\n' '  Krawl is a command line utility to scan pods and prints name of errored pods   ' printf '%s\n\n' ' +and containers within. To use it as kubernetes plugin, please check their page ' printf '%s\n' '=================================================================================' cat results.csv | sed 's/,/,|/g'| column -s ',' -t get_pod_events ``` * * * _此文最初发布在 [KRAWL 的 GitHub 仓库][2]下的 README 中，并被或许重用。_ -------------------------------------------------------------------------------- via: https://opensource.com/article/20/2/kubernetes-scanner 作者：[Abhishek Tamrakar][a] 选题：[lujun9972][b] 译者：[geekpi](https://github.com/geekpi) 校对：[校对者ID](https://github.com/校对者ID) 本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出 [a]: https://opensource.com/users/tamrakar [b]: https://github.com/lujun9972 [1]: https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/ship_captain_devops_kubernetes_steer.png?itok=LAHfIpek (Ship captain sailing the Kubernetes seas) [2]: https://github.com/abhiTamrakar/kube-plugins/tree/master/krawl [3]: https://opensource.com/sites/default/files/uploads/krawl_0.png (KRAWL script) [4]: mailto:abhishek.tamrakar08@gmail.com