最近看到一篇公眾號講了nginx-ingress-controller的應用。下面有人評論如何做日志持久化，剛好工作上遇到該問題，整理一個方案，僅供參考。
nginx-ingress-controller的日志
nginx-ingress-controller的日志包括三個部分：
- controller日志： 輸出到stdout，通過啟動參數中的–log_dir可已配置輸出到文件，重定向到文件后會自動輪轉，但不會自動清理
- accesslog：輸出到stdout，通過nginx-configuration中的字段可以配置輸出到哪個文件。輸出到文件后不會自動輪轉或清理
- errorlog：輸出到stderr，配置方式與accesslog類似。
給controller日志落盤
- 給nginx-ingress-controller掛一個hostpath： /data/log/nginx_ingress_controller/ 映射到容器里的/var/log/nginx_ingress_controller/ ，
- 給nginx-ingress-controller配置log-dir和logtostderr參數，將日志重定向到/var/log/nginx_ingress_controller/中。
controller的日志需要做定時清理。由于controller的日志是通過klog(k8s.io/klog)輸出的，會進行日志滾動，所以我們通過腳本定時清理一定時間之前的日志文件即可。
給nginx日志落盤
修改configmap： nginx-configuration。配置accesslog和errorlog的輸出路徑，替換默認的stdout和stderr。輸出路徑我們可以與controller一致，便于查找。
accesslog和errorlog都只有一個日志文件，我們可以使用logrotate進行日志輪轉，將輸出到宿主機上的日志進行輪轉和清理。配置如：
$ cat /etc/logrotate.d/nginx.log
/data/log/nginx_ingress_controller/access.log {
su root list
rotate 7
daily
maxsize 50M
copytruncate
missingok
create 0644 www-data root
}
官方提供的模板中，nginx-ingress-controller默認都是以33這個用戶登錄啟動容器的，因此掛載hostpath路徑時存在權限問題。我們需要手動在機器上執行chown -R 33:33 /data/log/nginx_ingress_controller.
自動化ops
nginx日志落盤中，第2、3兩點均需要人工運維，有什么解決辦法嗎？
問題的關鍵是：有什么辦法可以在nginx-ingress-controller容器啟動之前加一個hook，將宿主機的指定目錄執行chown呢？
可以用initContainer。initcontainer必須在containers中的容器運行前運行完畢并成功退出。利用這一k8s特性，我們開發一個docker image，里面只執行如下腳本：
#!/bin/bash
logdir=$LOG_DIR
userID=$USER_ID
echo "try to set dir: $logdir 's group as $userID"
chown -R $userID:$userID $logdir
腳本讀取一些環境變量， 確認需要修改哪個目錄，改成怎樣的user group。
將腳本打包成dockerimage， 放在nginx-ingress-controller的deploy yaml中，作為initcontainers。 注意要對該initcontainer配置環境變量和volumeMount.
再說第二點，我們注意到nginx-ingress-controller的基礎鏡像中就自帶了logrotate，那么問題就簡單了，我們將寫好的logrotate配置文件以configmap的形式掛載到容器中就可以了。
一個deploy yaml如下：
---
apiVersion: v1
kind: Service
metadata:
name: ingress-nginx
namespace: kube-system
spec:
type: ClusterIP
ports:
- name: http
port: 80
targetPort: 80
protocol: TCP
- name: https
port: 443
targetPort: 443
protocol: TCP
selector:
app: ingress-nginx
---
apiVersion: v1
kind: Service
metadata:
name: default-http-backend
namespace: kube-system
labels:
app: default-http-backend
spec:
ports:
- port: 80
targetPort: 8080
selector:
app: default-http-backend
---
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
name: default
namespace: kube-system
spec:
backend:
serviceName: default-http-backend
servicePort: 80
---
kind: ConfigMap
apiVersion: v1
metadata:
name: nginx-configuration
namespace: kube-system
labels:
app: ingress-nginx
data:
use-forwarded-headers: "true"
# 此處配置nginx日志的重定向目標
access-log-path: /var/log/nginx_ingress_controller/access.log
error-log-path: /var/log/nginx_ingress_controller/error.log
---
# 創建一個configmap，配置nginx日志的輪轉策略，對應的是nginx日志在容器內的日志文件
apiVersion: v1
data:
nginx.log: |
{{ user_nginx_log.host_path }}/access.log {
rotate {{ user_nginx_log.rotate_count }}
daily
maxsize {{ user_nginx_log.rotate_size }}
minsize 10M
copytruncate
missingok
create 0644 root root
}
{{ user_nginx_log.host_path }}/error.log {
rotate {{ user_nginx_log.rotate_count }}
daily
maxsize {{ user_nginx_log.rotate_size }}
minsize 10M
copytruncate
missingok
create 0644 root root
}
kind: ConfigMap
metadata:
name: nginx-ingress-logrotate
namespace: kube-system
---
kind: ConfigMap
apiVersion: v1
metadata:
name: tcp-services
namespace: kube-system
---
kind: ConfigMap
apiVersion: v1
metadata:
name: udp-services
namespace: kube-system
---
apiVersion: v1
kind: ServiceAccount
metadata:
name: nginx-ingress-serviceaccount
namespace: kube-system
---
apiVersion: rbac.authorization.k8s.io/v1beta1
kind: ClusterRole
metadata:
name: nginx-ingress-clusterrole
rules:
- apiGroups:
- ""
resources:
- configmaps
- endpoints
- nodes
- pods
- secrets
verbs:
- list
- watch
- apiGroups:
- ""
resources:
- nodes
verbs:
- get
- apiGroups:
- ""
resources:
- services
verbs:
- get
- list
- watch
- apiGroups:
- "extensions"
resources:
- ingresses
verbs:
- get
- list
- watch
- apiGroups:
- ""
resources:
- events
verbs:
- create
- patch
- apiGroups:
- "extensions"
resources:
- ingresses/status
verbs:
- update
---
apiVersion: rbac.authorization.k8s.io/v1beta1
kind: Role
metadata:
name: nginx-ingress-role
namespace: kube-system
rules:
- apiGroups:
- ""
resources:
- configmaps
- pods
- secrets
- namespaces
verbs:
- get
- apiGroups:
- ""
resources:
- configmaps
resourceNames:
# Defaults to "<election-id>-<ingress-class>"
# Here: "<ingress-controller-leader>-<nginx>"
# This has to be adapted if you change either parameter
# when launching the nginx-ingress-controller.
- "ingress-controller-leader-nginx"
verbs:
- get
- update
- apiGroups:
- ""
resources:
- configmaps
verbs:
- create
- apiGroups:
- ""
resources:
- endpoints
verbs:
- get
---
apiVersion: rbac.authorization.k8s.io/v1beta1
kind: RoleBinding
metadata:
name: nginx-ingress-role-nisa-binding
namespace: kube-system
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: Role
name: nginx-ingress-role
subjects:
- kind: ServiceAccount
name: nginx-ingress-serviceaccount
namespace: kube-system
---
apiVersion: rbac.authorization.k8s.io/v1beta1
kind: ClusterRoleBinding
metadata:
name: nginx-ingress-clusterrole-nisa-binding
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: ClusterRole
name: nginx-ingress-clusterrole
subjects:
- kind: ServiceAccount
name: nginx-ingress-serviceaccount
namespace: kube-system
---
apiVersion: apps/v1
kind: DaemonSet
metadata:
name: ingress-nginx
namespace: kube-system
spec:
selector:
matchLabels:
app: ingress-nginx
template:
metadata:
labels:
app: ingress-nginx
annotations:
prometheus.io/port: '10254'
prometheus.io/scrape: 'true'
spec:
serviceAccountName: nginx-ingress-serviceaccount
tolerations:
- key: dedicated
value: ingress-nginx
effect: NoSchedule
affinity:
nodeAffinity:
requiredDuringSchedulingIgnoredDuringExecution:
nodeSelectorTerms:
- matchExpressions:
- key: "system/ingress"
operator: In
values:
- "true"
dnsPolicy: ClusterFirstWithHostNet
hostNetwork: true
# 配置initcontainer，確保在nginx-ingress-controller容器啟動前將日志目錄的權限配置好
initContainers:
- name: adddirperm
image: "{{ image_registry.addr }}/{{ image.adddirperm }}"
env:
- name: LOG_DIR
value: /var/log/nginx_ingress_controller
- name: USER_ID
value: "33"
volumeMounts:
- name: logdir
mountPath: /var/log/nginx_ingress_controller
containers:
- name: nginx-ingress-controller
image: "{{ image_registry.addr }}/{{ image.ingress }}"
imagePullPolicy: IfNotPresent
args:
- /nginx-ingress-controller
- --default-backend-service=$(POD_NAMESPACE)/default-http-backend
- --configmap=$(POD_NAMESPACE)/nginx-configuration
- --tcp-services-configmap=$(POD_NAMESPACE)/tcp-services
- --udp-services-configmap=$(POD_NAMESPACE)/udp-services
- --publish-service=$(POD_NAMESPACE)/ingress-nginx
- --annotations-prefix=nginx.ingress.kubernetes.io
# 設置controller日志的輸出路徑和方式
- --log_dir=/var/log/nginx_ingress_controller
- --logtostderr=false
securityContext:
capabilities:
drop:
- ALL
add:
- NET_BIND_SERVICE
# www-data -> 33
runAsUser: 33
env:
- name: POD_NAME
valueFrom:
fieldRef:
fieldPath: metadata.name
- name: POD_NAMESPACE
valueFrom:
fieldRef:
fieldPath: metadata.namespace
ports:
- name: http
containerPort: 80
- name: https
containerPort: 443
resources:
requests:
cpu: 100m
memory: 256Mi
livenessProbe:
failureThreshold: 3
httpGet:
path: /healthz
port: 10254
scheme: HTTP
initialDelaySeconds: 10
periodSeconds: 10
successThreshold: 1
timeoutSeconds: 1
readinessProbe:
failureThreshold: 3
httpGet:
path: /healthz
port: 10254
scheme: HTTP
periodSeconds: 10
successThreshold: 1
timeoutSeconds: 1
volumeMounts:
# 配置掛載容器中控制器組件和nginx的日志輸出路徑
- name: logdir
mountPath: /var/log/nginx_ingress_controller
# 配置nginx日志的logrotate配置掛載路徑
- name: logrotateconf
mountPath: /etc/logrotate.d/nginx.log
subPath: nginx.log
volumes:
# 控制器組件和nginx的日志輸出路徑為宿主機的hostpath
- name: logdir
hostPath:
path: {{ user_nginx_log.host_path }}
type: ""
# nginx日志的輪轉配置文件來自于configmap
- name: logrotateconf
configMap:
name: nginx-ingress-logrotate
items:
- key: nginx.log
path: nginx.log
---
apiVersion: apps/v1
kind: DaemonSet
metadata:
name: default-http-backend
namespace: kube-system
labels:
app: default-http-backend
spec:
selector:
matchLabels:
app: default-http-backend
template:
metadata:
labels:
app: default-http-backend
spec:
terminationGracePeriodSeconds: 60
tolerations:
- key: dedicated
value: ingress-nginx
effect: NoSchedule
affinity:
nodeAffinity:
requiredDuringSchedulingIgnoredDuringExecution:
nodeSelectorTerms:
- matchExpressions:
- key: "system/ingress"
operator: In
values:
- "true"
containers:
- name: default-http-backend
# Any image is permissible as long as:
# 1. It serves a 404 page at /
# 2. It serves 200 on a /healthz endpoint
image: "{{ image_registry.addr }}/{{ image.http_backend }}"
imagePullPolicy: IfNotPresent
livenessProbe:
httpGet:
path: /healthz
port: 8080
scheme: HTTP
initialDelaySeconds: 30
timeoutSeconds: 5
ports:
- containerPort: 8080
resources:
limits:
cpu: 10m
memory: 20Mi
requests:
cpu: 10m
memory: 20Mi
---
最后，有的人建議將initcontainer去掉，改為基于原有的nginx-ingress-controller鏡像加一層layer，將配置路徑權限的腳本放在該層執行。 個人認為這種方法既不美觀，也不方便。唯一的好處僅在于deploy yaml仍然簡潔（但少不了volumeMount之類的配置）。不過還是看個人使用感受吧~
到此這篇關于nginx-ingress-controller日志持久化方案的解決的文章就介紹到這了,更多相關nginx ingress controller日志持久化內容請搜索腳本之家以前的文章或繼續瀏覽下面的相關文章希望大家以后多多支持腳本之家！
