1. 启动电脑进入BIOS，打开高级(Advanced)菜单 / APM，启用Power On By PCIE功能选项。
2. Windows 10自动安装的网卡驱动Realtek PCIe GBE Family Controller 9.x版对WoL的支持有问题，关机后电脑无法再被网络唤醒。从Realtek网站下载安装最新的10.x版驱动可以解决这个问题。
3. 发送WoL开机魔术报文的工具程序很多。Android上的Wake On Lan应用的设计看上去很用心，比较好用。
Raspbian中文和国际化环境设置
本文介绍Raspbian Jessie的中文和国际化环境设置，使之能在图形界面上输入和显示中文和其他语言文字，并且在图形界面和虚拟控制台上都能显示欧洲字符，以及通过altgr-intl键盘布局输入欧洲字符。
一、图形界面
- 安装中文字体和输入法：
$ sudo apt-get update $ sudo apt-get install ttf-wqy-microhei fcitx-table-wbpy
- 单击图形界面主菜单 Menu > Preferences > Raspberry Pi Configuration，打开Localisation选项卡，分别设置Locale、Timezone和Keyboard：
- Set Locale... : zh (Chinese)
- Set Timezone... : Asia / Shanghai
- Set Keyboard... : United States / English (international AltGr dead keys)
然后，单击OK按钮，并在”Reboot needed"对话框上单击Yes按钮确认重启。
Configuring a Ubuntu 14.04 real server for an LVS/Tun cluster
To setup an LVS/Tun mode LVS cluster, we must configure, on the real servers, an IP tunneling network interface with the cluster Virtual IP on it, and in the meantime handle the following two issues:
- Disable source validation (rp_filter) on the IP tunneling interface.
- Inhibit ARP responses for VIP on the LAN interface in case the real server is in the same broadcast domain as is the load balancer.
In the following tutorial, we'll configure Ubuntu 14.04 as a real server for an LVS/Tun cluster.
Continue reading Configuring a Ubuntu 14.04 real server for an LVS/Tun cluster
Configuring IPsec IKEv2 in OpenWrt 15.05
The interoperability of IPsec implementations on various platforms has been becoming better and better over the last few years. For example, Windows 7 and newer releases fully support the IKEv2 (RFC 4306) and MOBIKE (RFC 4555) standards, and iOS started to support configuration of IKEv2 in the GUI since version 9.0.
In this tutorial, we'll install strongSwan 5.3.3 in openwrt 15.05, configure it to provide IKEv2 service with public key authentication of the server and username/password based authentication of the clients using EAP-MSCHAP v2, and finally setup the VPN clients in Windows, Android and iOS so they can connect to it. Much of the complexity of IKEv2 configuration lies in the creation of SSL certificates.
Installation
First of all, install necessary strongSwan packages in openwrt 15.05:
root@OpenWrt:~# opkg update
root@OpenWrt:~# opkg install strongswan-minimal strongswan-mod-eap-mschapv2 strongswan-mod-eap-identity strongswan-mod-constraints strongswan-mod-md5 strongswan-mod-pem strongswan-mod-pkcs1 strongswan-mod-revocation
GnuPG——每个人都可以使用的高强度加密软件
PGP(Pretty Good Privay)是一套用于数据加密、解密和数据签名生成、验证的软件。它由一系列散列、数据压缩、对称密钥加密和公钥加密算法组成。每种功能提供几种算法可供选择。
不对称的公钥加密算法使密钥的安全交换变得简单，通常使用收件人的公钥来加密只用一次的会话密钥，再用安全的对称加密算法和这个会话密钥对数据进行加密。每个人都可以生成自己的公钥/私钥对。公钥，顾名思义就是可以公开的密钥，可以分享给所有跟你联系的人，也可以上传到用于交换公钥的OpenPGP公钥服务器；而私钥必须严格保密，不跟任何人分享。别人使用你的公钥加密的信息，只有你使用对应的私钥才能解密。在数字签名时，则使用你自己的私钥对数据进行签名，而别人用你的公钥对你的签名进行验证，确保数据在传送过程中未被篡改。
公钥算法在数学上保证无法通过公钥计算出对应的私钥。以目前的技术手段，如果使用计算集群或量子计算机可能可以破解的话，也必须付出高昂的成本代价。对我们个人或一般企业而言，PGP加密套件提供了足够的加密强度。
GnuPG(Gnu Privacy Guard)是以GPL许可协议发行的，免费、开源、完整的PGP替代软件，遵从OpenPGP标准（RFC 4880）。
Continue reading GnuPG——每个人都可以使用的高强度加密软件
A Dummie’s Guide to Flashing Factory Firmware on Nexus 7 [2013]
This guide aims to teach people with basic computer skills to flash factory firmware image on Nexus 7 [2013] using Windows 7/10. It should apply to other modern stock Android devices.
Note: To prevent unauthorized access, unlocking the bootloader will delete all personal data on the device. Therefore, you must backup important data first before proceeding with the following procedure.
Continue reading A Dummie’s Guide to Flashing Factory Firmware on Nexus 7 [2013]
Perl One Liners
-
将字符串进行URL编码(Percent-encoding, aka URL encoding)
$ ls *.mp4 | perl -MURI::Escape -lpe '$_ = uri_escape($_)'
或者
$ ls *.mp4 | perl -lpe 's/([^\w\-~.])/sprintf("%%%02X", ord($1))/seg'
Keeping track of svn repositories using git
- Clone an svn repository with entire history.
git svn clone --prefix=origin/ svn://svn.dd-wrt.com/DD-WRT
Note: This can be very time-consuming on a large svn repository, esp. when the network connectivity is poor.
git svn clone --prefix=origin/ -r 28015:HEAD svn://svn.dd-wrt.com/DD-WRT
cd DD-WRT while ! git svn fetch; do sleep 10; done
git svn rebase
git checkout `git svn find-rev r28015`
git checkout master
git clean -n git clean -f
Migrating a CentOS-3 physical machine into a KVM virtual machine
I documented the following procdure when migrating an 11-yr-old CentOS-3 server system into a KVM virtual machine early last year after its CPU cooling fan finally wore out.
Continue reading Migrating a CentOS-3 physical machine into a KVM virtual machine
CentOS 7的引导程序Grub2执行halt指令失败
在许多ACPI管理的系统里，CentOS 7引导程序Grub2在执行关机"halt"指令时会失败，屏幕显示如下出错信息：
grub> halt Unknown opcode 0x6 Unknown opcode 0x12 Unknown opcode 0x7d ACPI shutdown failed
此时，只能长按电源按钮强行关机。
Continue reading CentOS 7的引导程序Grub2执行halt指令失败