PHPor 的Blog – 第30页

vnc in openstack

在openstack管理的虚拟机中启动vnc时，:1 是启动不了的，似乎是被kvm已某种方式给占用了，而这种占用方式似乎并不依赖虚拟机中的vnc软件。

浏览器中的vnc性能和体验都不如vnc客户端软件

cloud-init 工作原理 – 每天5分钟玩转 OpenStack（171） – CloudMan6的博客 – CSDN博客

http://m.blog.csdn.net/CloudMan6/article/details/68952153

Management Tools – KVM

http://www.linux-kvm.org/page/Management_Tools

mac brew HOMEBREW_NO_GITHUB_API

brew install spinx-build 的时候可能会遇到如下错误：

/System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/open-uri.rb:353:in `open_http': 422 Unprocessable Entity (GitHub::Error)
	from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/open-uri.rb:709:in `buffer_open'
	from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/open-uri.rb:210:in `block in open_loop'
	from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/open-uri.rb:208:in `catch'
	from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/open-uri.rb:208:in `open_loop'
	from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/open-uri.rb:149:in `open_uri'
	from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/open-uri.rb:689:in `open'
	from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/open-uri.rb:30:in `open'
	from /usr/local/Library/Homebrew/utils.rb:367:in `open'
	from /usr/local/Library/Homebrew/utils.rb:397:in `issues_matching'
	from /usr/local/Library/Homebrew/utils.rb:425:in `issues_for_formula'
	from /usr/local/Library/Homebrew/exceptions.rb:145:in `fetch_issues'
	from /usr/local/Library/Homebrew/exceptions.rb:141:in `issues'
	from /usr/local/Library/Homebrew/exceptions.rb:184:in `dump'
	from /usr/local/Library/brew.rb:167:in `rescue in <main>'
	from /usr/local/Library/brew.rb:65:in `<main>'

/System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/open-uri.rb:353:in `open_http': 422 Unprocessable Entity (GitHub::Error)

from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/open-uri.rb:709:in `buffer_open'

from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/open-uri.rb:210:in `block in open_loop'

from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/open-uri.rb:208:in `catch'

from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/open-uri.rb:208:in `open_loop'

from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/open-uri.rb:149:in `open_uri'

from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/open-uri.rb:689:in `open'

from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/open-uri.rb:30:in `open'

from /usr/local/Library/Homebrew/utils.rb:367:in `open'

from /usr/local/Library/Homebrew/utils.rb:397:in `issues_matching'

from /usr/local/Library/Homebrew/utils.rb:425:in `issues_for_formula'

from /usr/local/Library/Homebrew/exceptions.rb:145:in `fetch_issues'

from /usr/local/Library/Homebrew/exceptions.rb:141:in `issues'

from /usr/local/Library/Homebrew/exceptions.rb:184:in `dump'

from /usr/local/Library/brew.rb:167:in `rescue in <main>'

from /usr/local/Library/brew.rb:65:in `<main>'

修改 /usr/local/Library/Homebrew/utils.rb 的代码，打印url看看：

https://api.github.com/search/issues?q=sphinx+repo:Homebrew/homebrew+in:title+state:open&amp;per_page=100

1	https://api.github.com/search/issues?q=sphinx+repo:Homebrew/homebrew+in:title+state:open&per_page=100

莫非访问不了api.github.com ？

$ curl "https://api.github.com/search/issues?q=sphinx+repo:Homebrew/homebrew+in:title+state:open&per_page=100"
{
  "message": "Validation Failed",
  "errors": [
    {
      "message": "The listed users and repositories cannot be searched either because the resources do not exist or you do not have permission to view them.",
      "resource": "Search",
      "field": "q",
      "code": "invalid"
    }
  ],
  "documentation_url": "https://developer.github.com/v3/search/"
}

$ curl "https://api.github.com/search/issues?q=sphinx+repo:Homebrew/homebrew+in:title+state:open&per_page=100"

{

"message": "Validation Failed",

"errors": [

{

"message": "The listed users and repositories cannot be searched either because the resources do not exist or you do not have permission to view them.",

"resource": "Search",

"field": "q",

"code": "invalid"

}

"documentation_url": "https://developer.github.com/v3/search/"

}

看起来是有返回值的，而且是合法的json，继续看 /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/open-uri.rb 的代码，发现很可能是httpcode的问题：

curl -v "https://api.github.com/search/issues?q=sphinx+repo:Homebrew/homebrew+in:title+state:open&amp;per_page=100"

1	curl -v "https://api.github.com/search/issues?q=sphinx+repo:Homebrew/homebrew+in:title+state:open&per_page=100"

发现http code为 422 ，而/System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/open-uri.rb 遇到 422 是走异常逻辑的，如果能简单修改代码使其认为是正常似乎是可以的；但是mac 不让修改/System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/open-uri.rb ， root账号也不行

回头看 /usr/local/Library/Homebrew/utils.rb ，发现如下逻辑：

export HOMEBREW_NO_GITHUB_API=1

问题解决

其实 spinx-build 是在生成man page的时候用到的，某些情况下，大可不必非要去生成man page

虚拟机镜像操作

软件包： libguestfs-tools

这里的 guestfish 挺不错的

查看镜像分区及其使用情况：

# virt-df -a centos7.3.raw -h|column -t
文件系统 大小 已用空间 可用空间 使用百分比%
centos7.3.raw:/dev/sda2 497M 147M 350M 30%
centos7.3.raw:/dev/sda5 100M 0 100M 0%
centos7.3.raw:/dev/sda6 42G 2.1G 40G 5%

# virt-df -a centos7.3.raw -h|column -t

文件系统大小已用空间可用空间使用百分比%

centos7.3.raw:/dev/sda2 497M 147M 350M 30%

centos7.3.raw:/dev/sda5 100M 0 100M 0%

centos7.3.raw:/dev/sda6 42G 2.1G 40G 5%

查看镜像中的文件信息

virt-ls -a centos7.3.img -l /

1

virt-ls -a centos7.3.img -l /
copy 文件到镜像

virt-copy-in -a centos7.3.img /tmp/hello.txt /tmp/

1

virt-copy-in -a centos7.3.img /tmp/hello.txt /tmp/
查看镜像中的文件

virt-cat -a centos7.3.img /tmp/hello.txt

1

virt-cat -a centos7.3.img /tmp/hello.txt
查看镜像中的文件系统分区信息： virt-filesystems –long –parts –blkdevs -h -a CentOS-7-x86_64-GenericCloud-1708.raw

virt-resize: –shrink 并不能让镜像文件变的更小（反而变大了）

virt-sparsify 可以使得一个镜像文件变成一个稀疏文件，对于发布、存储镜像很有必要

Building a cloud ready linux image locally using KVM | Ravello Blog

https://blogs.oracle.com/ravello/kvm-for-cloud-linux-image

Refactoring a Dockerfile for Image Size

http://blog.replicated.com/refactoring-a-dockerfile-for-image-size/

1. 尽量减少不必要的包

2. 包管理器自动安装的包不一定都是必须的，可能只是建议安装

resolv.conf 之options都有啥

你没法通过options来禁用ipv6解析
single-request：用来指定分别执行A和AAAA解析；即，收到A记录解析的结果后在发送AAAA记录解析请求；默认情况下，同时在一个连接上发送A和AAAA的解析，这样效率会高一倍；然而，有些dns server不能很好地处理这种请求方式，很可能不能正确地返回AAAA的响应，以至于请求会超时
single-request-reopen：强制A和AAAA的解析在两个连接中处理（主要体现在连接的源端口不同）

参考：

http://man7.org/linux/man-pages/man5/resolv.conf.5.html

openstack 与 ldap的集成

按照下面参考中的做法，添加一个认证的中间件就可以搞定

参考： https://docs.openstack.org/keystone/latest/advanced-topics/external-auth.html