小結

在使用Kubernetes部署Wordpress時返回了兩個問題:

• Function not implemented: AH00141: Could not initialize random number generator

• chown: changing ownership of '.': Operation not permitted

對這個兩個返回錯誤，進行了解決。

問題1解決

Function not implemented: AH00141: Could not initialize random number generator具體返回的錯誤如下：

[root@Master ~]# kubectl get pods -o wide
NAME              READY     STATUS             RESTARTS   AGE       IP           NODE
mysql-d7xcd       1/1       Running            0          12h       172.17.0.3   192.168.238.135
wordpress-26lwg   0/1       CrashLoopBackOff   143        11h       172.17.0.5   192.168.238.135
wordpress-2l6v2   0/1       Error              143        11h       172.17.0.3   192.168.238.134
wordpress-9g6qp   0/1       CrashLoopBackOff   142        11h       172.17.0.4   192.168.238.135
wordpress-vz3tk   0/1       CrashLoopBackOff   143        11h       172.17.0.2   192.168.238.134
[root@Master ~]# 
[root@Master ~]# kubectl logs wordpress-vz3tk
WordPress not found in /var/www/html - copying now...
Complete! WordPress has been successfully copied to /var/www/html
No 'wp-config.php' found in /var/www/html, but 'WORDPRESS_...' variables supplied; copying 'wp-config-docker.php' (WORDPRESS_PORT WORDPRESS_PORT_80_TCP WORDPRESS_PORT_80_TCP_ADDR WORDPRESS_PORT_80_TCP_PORT WORDPRESS_PORT_80_TCP_PROTO WORDPRESS_SERVICE_HOST WORDPRESS_SERVICE_PORT)
[Sun Aug 13 03:23:30.542592 2023] [:crit] [pid 1] (38)Function not implemented: AH00141: Could not initialize random number generator
[root@Master ~]# 

查看具體原因，是因為Linux Kernel的版本太低，缺失了Apache2的一些依賴，只要升級Linux Kernel版本就可以解決問題，進行了驗證，確實可以解決問題。

參考How to Upgrade Linux Kernel on CentOS ，如下步驟：

[root@Node1 ~]# yum update -y
[root@Node1 ~]# uname -r
3.10.0-514.el7.x86_64
[root@Node1 ~]# rpm --import https://www.elrepo.org/RPM-GPG-KEY-elrepo.org
[root@Node1 ~]# yum install -y https://www.elrepo.org/elrepo-release-7.el7.elrepo.noarch.rpm
[root@Node1 ~]# yum --enablerepo=elrepo-kernel install -y kernel-ml
[root@Node1 ~]# grub2-mkconfig -o /boot/grub2/grub.cfg
Generating grub configuration file ...
Found linux image: /boot/vmlinuz-6.4.10-1.el7.elrepo.x86_64
Found initrd image: /boot/initramfs-6.4.10-1.el7.elrepo.x86_64.img
Found linux image: /boot/vmlinuz-3.10.0-1160.95.1.el7.x86_64
Found initrd image: /boot/initramfs-3.10.0-1160.95.1.el7.x86_64.img
Found linux image: /boot/vmlinuz-3.10.0-514.el7.x86_64
Found initrd image: /boot/initramfs-3.10.0-514.el7.x86_64.img
Found linux image: /boot/vmlinuz-0-rescue-651a89d2f1bc4d1d890d6b935d971e00
Found initrd image: /boot/initramfs-0-rescue-651a89d2f1bc4d1d890d6b935d971e00.img
done
[root@Node1 ~]# grub2-set-default 0
[root@Node1 ~]# reboot
[root@Node1 ~]# uname -r
6.4.10-1.el7.elrepo.x86_64

重新部署wordpress docker，問題解決。

問題2解決

Wordpress共享了NFS掛載的卷，yaml文件如下：

[root@Master ~]# vim wordpress_rc_update.yaml apiVersion: v1
kind: ReplicationController
metadata:name: wordpress
spec:replicas: 2selector:name: wordpresstemplate:metadata:labels:name: wordpressspec:containers:- name: wordpressimage: wordpress:v1ports:- name: webcontainerPort: 80env:- name: MYSQL_SERVICE_HOSTvalue: 10.254.225.126volumeMounts:- name: datamountPath: /var/www/htmlvolumes:- name: datahostPath:path: /nfs

部署時碰到以下問題：

[root@Master ~]# kubectl logs wordpress-qz6hh
chown: changing ownership of '.': Operation not permitted
[root@Master ~]# kubectl logs wordpress-v05h7
chown: changing ownership of '.': Operation not permitted

這里牽扯到權限問題，解決辦法：

[root@Master ~]#  chmod o+w /nfs/
[root@Master ~]# vim /etc/exports
/nfs    *(rw,sync,no_root_squash)
[root@Master ~]# systemctl restart nfs
[root@Node1 ~]# mount Master:/nfs/ /nfs/
[root@Node1 ~]# chmod o+w /nfs/
[root@Node2 ~]#  mount Master:/nfs/ /nfs/
[root@Node2 ~]# chmod o+w /nfs/

重新部署wordpress docker，問題解決。

參考

How to Upgrade Linux Kernel on CentOS
(38)Function not implemented: AH00141: Could not initialize random number generator #1574
chown on a mounted NFS partition gives “Operation not permitted”