Install x86_64 JDK via sdkman on M1/M2/M3/M4 macOS

Sometimes we need to install an x86_64 JDK on the M1/M2/M3/M4 macOS for some reason, for example, I was testing Kafka Stream 2.7 application locally on a M3 MacBook Pro. Its Rocksdb library didn’t have the native lib for M series Macs, I had to install an x86_64 JDK on it to run the application

By default, the sdkman only lists the JDKs that match the hardware architecture. But we can edit the ~/.sdkman/var/platform by changing darwinarm64 to darwinx64 temporally. So the steps would be:

  1. Edit ~/.sdkman/var/platform and replace the darwinarm64 with darwinx64
  2. Run sdk flush to flush sdkman’s local state
  3. Run sdk list java and the non-installed listed JDKs which should be already X64 version
  4. Run sdk install java xxx as normal and sdk use java xxx, now the installed JDK should
  5. Run cat which java | file - we will see /dev/stdin: Mach-O 64-bit executable x86_64
  6. Don’t forget to change the darwinx64 back to darwinarm64 after finishing the testing of X64 JDK.

The exception when an ARM JDK is used.

java.lang.UnsatisfiedLinkError: /private/var/folders/h0/m23_22tn3cg71g72b_c4tmgr0000gn/T/librocksdbjni4698946407096025405.jnilib: dlopen(/private/var/folders/h0/m23_22tn3cg71g72b_c4tmgr0000gn/T/librocksdbjni4698946407096025405.jnilib, 0x0001): tried: '/private/var/folders/h0/m23_22tn3cg71g72b_c4tmgr0000gn/T/librocksdbjni4698946407096025405.jnilib' (mach-o file, but is an incompatible architecture (have 'x86_64', need 'arm64e' or 'arm64')), '/System/Volumes/Preboot/Cryptexes/OS/private/var/folders/h0/m23_22tn3cg71g72b_c4tmgr0000gn/T/librocksdbjni4698946407096025405.jnilib' (no such file), '/private/var/folders/h0/m23_22tn3cg71g72b_c4tmgr0000gn/T/librocksdbjni4698946407096025405.jnilib' (mach-o file, but is an incompatible architecture (have 'x86_64', need 'arm64e' or 'arm64'))

Fix mysqlbinlog command missing for docker containers

Sometimes we want to use the MySQL docker container to test some binlog-related features, but unfortunately, the default tag of the official docker image doesn’t contain the binlog utilities, please refer to https://github.com/docker-library/mysql/issues/907 and https://github.com/docker-library/mysql/issues/847

What shall we do about this case?

For testing, it’s pretty straightforward: just use the Debian-based images

for example previously used an image that doesn’t contain the binlog tools: mysql:5.7.39, then we switch to using mysql:5.7.39-debian, the mysqlbinlog will appear after we do the switch.

windows 升级遇到 0x80092004 错误

windows 升级遇到 0x80092004 错误时候需要单独下载两个更新文件，并手动更新

servicing stack update

https://support.microsoft.com/en-sg/help/4490628/servicing-stack-update-for-windows-7-sp1-and-windows-server-2008-r2

SHA-2 code signing support update

https://support.microsoft.com/en-us/help/4474419/sha-2-code-signing-support-update

Could not resolve host:mirrors.cloud.aliyuncs.com

通过yum 在阿里云的Centos ECS中安装或更新软件的时候有时会遇到

http://mirrors.cloud.aliyuncs.com/centos/7/os/x86_64/repodata/repomd.xml: [Errno 14] curl#6 – “Could not resolve host: mirrors.cloud.aliyuncs.com; Unknown error”

出现这种问题可能是因为把专有网络的镜像复制到了经典网络，而未修改阿里云yum源的域名，以下是阿里云不同的网络类型所对应的的域名

  • （默认）公网：mirrors.aliyun.com （需要实例具有公网访问）
  • 专有网络VPC内网：mirrors.cloud.aliyuncs.com
  • 经典网络内网：mirrors.aliyuncs.com

对于Centos/Alibaba Cloud Linux

需要编辑/etc/yum.repo.d/下面的配置文件，删除 mirrors.cloud.aliyuncs.com或替换为mirrors.aliyun.com

yum clean all

yum make cache

对于Debian/Ubuntu 类系统

我们编辑/etc/apt/sources.list 以及/etc/apt/sources.list.d/ 下的文件

替换域名为当前实例网络类型对应的域名

  • （默认）公网：mirrors.aliyun.com （需要实例具有公网访问）
  • 专有网络VPC内网：mirrors.cloud.aliyuncs.com
  • 经典网络内网：mirrors.aliyuncs.com

一般我们通过sed 命令一键替换

比如我们要把专有网络VPC内网源的域名更换为公网源的域名我们可以这样做：

sed -i 's/mirrors.cloud.aliyuncs.com/mirrors.aliyun.com/g' /etc/yum.repos.d/CentOS-Base.repo

在macOS上安装配置selenium-python

1. 用homebrew安装较新版本的python2.7

brew install python

sudo -H easy_install pip

 

2. 安装selenium

sudo -H pip install selenium

 

3. 安装selenium webdriver

Firefox:
到https://github.com/mozilla/geckodriver/releases下载macOS版本的driver解压出来，复制到/usr/local/bin

sudo cp ~/Download/geckodriver /usr/local/bin

 

Chrome

到https://chromedriver.storage.googleapis.com/index.html下载chromedriver，和firefox版一样复制到/usr/local/bin

sudo cp ~/Download/chromedriver /usr/local/bin

 

4. 检查安装

在python console

from selenium import webdriver
browser = webdriver.Firefox()
browser.get('https://www.baidu.com')

 

能够成功打开浏览器，并打开网页，说明安装成功。

note: 必须要保证系统里面安装了Firefox或者Chrome浏览器
不然可能会有如下的异常：

selenium.common.exceptions.WebDriverException: Message: Expected browser binary location,
but unable to find binary in default location, no 'moz:firefoxOptions.binary' capability provided, and no binary flag set on the command line

 

升级阿里云centos kernel修复CVE-2016-5195(Dirty COW)

  1. 检查是否受影响： 
    wget https://access.redhat.com/sites/default/files/rh-cve-2016-5195_1.sh
bash ~/rh-cve-2016-5195_1.sh
Your kernel is 2.6.32-358.6.2.el6.x86_64 which IS vulnerable.
  2. 修改 /etc/yum.conf， 删除掉exclude的kernel部分 
    #exclude=*.i?86 kernel kernel-xen kernel-debug
exclude=*.i?86 kernel-xen kernel-debug
  3. 执行升级 
    yum update kernel
Loaded plugins: fastestmirror
Setting up Update Process
Loading mirror speeds from cached hostfile
 * base: mirrors.aliyuncs.com
 * epel: mirrors.aliyuncs.com
 * extras: mirrors.aliyuncs.com
 * updates: mirrors.aliyuncs.com
base                                                                                                                                   | 3.7 kB     00:00     
epel                                                                                                                                   | 4.3 kB     00:00     
extras                                                                                                                                 | 3.4 kB     00:00     
updates                                                                                                                                | 3.4 kB     00:00     
Resolving Dependencies
--> Running transaction check
---> Package kernel.x86_64 0:2.6.32-642.6.2.el6 will be installed
--> Finished Dependency Resolution

Dependencies Resolved

==============================================================================================================================================================
 Package                           Arch                              Version                                         Repository                          Size
==============================================================================================================================================================
Installing:
 kernel                            x86_64                            2.6.32-642.6.2.el6                              updates                             32 M

Transaction Summary
==============================================================================================================================================================
Install       1 Package(s)

Total download size: 32 M
Installed size: 131 M
Is this ok [y/N]: y
Downloading Packages:
kernel-2.6.32-642.6.2.el6.x86_64.rpm                                                                                                   |  32 MB     00:31     
Running rpm_check_debug
Running Transaction Test
Transaction Test Succeeded
Running Transaction
  Installing : kernel-2.6.32-642.6.2.el6.x86_64                                                                                                           1/1 
  Verifying  : kernel-2.6.32-642.6.2.el6.x86_64                                                                                                           1/1 

Installed:
  kernel.x86_64 0:2.6.32-642.6.2.el6                                                                                                                          

Complete!
  4. 重启服务器 
    reboot
  5. 再次执行脚本，确认修复 
    bash ~/rh-cve-2016-5195_1.sh
Your kernel is 2.6.32-642.6.2.el6.x86_64 which is NOT vulnerable.

 

iphone热点不能联网

 

打开iphone的热点功能，

笔记本能连接上，但是显示无internet连接，

查看ipconfig

无线局域网适配器 无线网络连接:

连接特定的 DNS 后缀 . . . . . . . :
自动配置 IPv4 地址 . . . . . . . : 169.254.64.152
子网掩码 . . . . . . . . . . . . : 255.255.0.0
默认网关. . . . . . . . . . . . . :

 

估计可能是iphone的dhcp功能有问题，重启iphone，还是不行，

把ip v4设置为手动，如下

无线局域网适配器 无线网络连接:

连接特定的 DNS 后缀 . . . . . . . :
IPv4 地址 . . . . . . . . . . . . : 172.20.10.2
子网掩码 . . . . . . . . . . . . : 255.255.255.240
默认网关. . . . . . . . . . . . . : 172.20.10.1

 

发现已经可以连接