51工具盒子用 KRAWL 脚本来识别 Kubernetes Pod 和容器中的错误。
当你使用 Kubernetes 运行容器时，你通常会发现它们堆积在一起。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。你可以使用前端工具（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，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。
先决条件 {#toc_1}
- 必须安装
kubectl。 - 集群的 kubeconfig 配置必须在它的默认位置（
$HOME/.kube/config）或已被导出到环境变量（KUBECONFIG=/path/to/kubeconfig）。
使用 {#toc_2}
$ ./krawl
脚本 {#toc_3}
#!/bin/bash
# AUTHOR: Abhishek Tamrakar
# EMAIL: abhishek.tamrakar08@gmail.com
# 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
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# 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 仓库下的 README 中，并被或许重用。
via: https://opensource.com/article/20/2/kubernetes-scanner
作者：Abhishek Tamrakar 选题：lujun9972 译者：geekpi 校对：wxy
