芳草苑

Category: 小小草

IT 技术领域学海无涯。其实任何领域都学海无涯，无非 IT 发展太快了，让我有更多嘘唏。希望我掌握的技术有如小小草，虽然渺小，却有旺盛的生命力。

  • Install Fedora 10 on a machine with Intel 845 chipset

    前面讲过，Fedora 是不太注重兼容性的，碰上杂七杂八问题的概率就高。我在 Dell Dimension 2400 上安装 Fedora 10 总是进行不下去，换一台机子也是如此，具体的症状是在 Live User login 界面时花屏、黑屏、或干脆死机。我猜是显卡驱动的原因，Google 了几下基本证实我的判断，问题集中在使用 Intel 845 chipset 的机型上。当年 Intel 845 的畅销如今使得面临这个问题的用户还不少。（但是 Fedora 为什么不解决一下这个问题？）

    原因定位得很快，对策就是让 Fedora Live CD 启动时不加载显卡驱动，或按特殊的参数加载显卡驱动。可是，具体怎么做？我又 Google 了好久，一开始找到的方法最后发现在 Fedora 10 上已经不适用了，这些过时的方法浪费我好多时间。我把我走过的弯路也写出来，希望后来者少走弯路。

    弯路一：输入启动参数 vmlinux initrd=initrd.img text，试图以文本方式安装，可 kernel 已经不叫 vmlinux，改称 vmlinux0，initrd.img 也不存在，改名 initrd0.img，但就算你把名称弄对了，也别想进入文本模式。

    弯路二：追加启动参数 linux xdriver=vesa resolution=1024×768 （我还试过 linux xdriver=vesa resolution=1024*768），试图加载 vesa 通用显卡驱动，强制分辨率。Fedora 10 根本不理这一套。

    真正能在 Intel 845 chipset 机型上成功安装 Fedora 10 的办法在 Fedora forum 上有提及，我这里总结一下：

  • 1and1 support is not professional

    I am quite happy with Godaddy’s product and service. However, virutalisation time is coming and my current dedicated server is not fast enough. Instead of going back to Godaddy for a VPS, I choose 1&1 as my new supplier.

    1&1 offer a slightly better price than Godaddy, but the cost saving is not the incentive of my switching supplier. I trust Godaddy better than 1&1. I think many people feel the same, which makes Godaddy has too many customers. It in turn overloads Godaddy’s servers. (Not efficient and responsive Godaddy’s servers forced me to learn a lot about CLI, which is good for me.)

    My reason of being a 1&1 sounds odd. Anyway, I am now a 1&1 customer. But they disappointed me on the first day after purchase.

    Before my purchase, I called 1&1 support asking how to order additional IPs because their standard checkout does not have this option. I was told I could order additional IPs after logging into my 1&1 account management (of course I have to purchase and get account open first).

    When I got account open, I could not find a link to order additional IPs. So the first support ticket to 1&1 support is “how can I order additional IPs”. Then the reply is “no, 1 VPS can only have 1 IP”!

    I have to write to them again to get IPs.

    The good thing is the IP coming with 1&1 VPS is UK based. I prefer UK IP to US IP for GEO SEO reasons. Before my purchase, I asked 1&1 support “will I get a UK IP” and was told “no, because all VPS are located in America”. So, why I get a UK IP eventually?

  • Config CentOS to use the latest software

    1and1 VPS OS 可选清单里没有 Fedora，不得不说是个遗憾。当然 CentOS 也不错，可是以前都没接触，使用 CentOS 会有很长的学习过程，但没办法，只能装个 CentOS 用用看。

    以前我调查过，CentOS 讲究兼容性，Fedora 追求技术领先。CentOS 安装真得比当初装 Fedora 要容易（Fedora 从6开始到10，我没有一次是一次启动就安装成功的），今天装CentOS 5很顺利（CentOS 兼容性真的那么好？还是我从 Fedora 学来的经验丰富了？）

    装完 CentOS，我就面临一个问题：不能 yum install nginx；yum install php 得来的版本也只是 5.1.6。这个简单的比较才觉得 Fedora 的好。我无法想象我还要下载编译 nginx（那一套我还不熟，怕搞砸了）。不过，Extra Packages for Enterprise Linux (EPEL) 已经做好了一个 repository，只要添加这个 repository，

    sudo rpm -Uvh http://download.fedora.redhat.com/pub/epel/5Server/x86_64/epel-release-5-3.noarch.rpm

    然后就可以用 yum install nginx。

    但是，yum install php 得来的版本只能是 5.1.6，目前还没找到好办法。

  • 一语惊醒梦中人

    由于某种原因，我删掉了 /usr/bin/php, /etc/php.ini 等文件，我指望 yum reinstall php 能把这些文件重新装回去。但是 yum install / remove / reinstall 交替使用了 n 次，还是没见这些文件。

    于是我又在想，可能 Fedora 把我以前的安装信息保存在某个地方，毕竟直接去删 /usr/bin/php, /etc/php.ini 等文件不是卸载 package 的正当做法，所以再次用 yum 安装时，它不会把这些文件送回来。怎么让 Fedora 认为我是要象第一次安装 php 那样把这些文件都给装上去呢？我想了好久不得要领，只好去 Fedora forum 提问，由于我的提问也没切中要害，一开始得到的回答也不得要领。

    直到突然一个好心人告诉我，/usr/bin/php 是在 php-cli package 里，/etc/php.ini 是在 php-common package 里。一语惊醒梦中人——怎么我总以为这些文件是由一个 php 全包了呢？

  • Session save path should be writable

    由于我系统里的 php session save path 是由当初 apache 创建的，改用 nginx 后就变成不可写了。但是，症状并不直观，php 照样能运行，phpMyAdmin 也能 login，还能查看各库各表的数据，但就是不能更新、删除，也无法 logout。无法 logout phpMyAdmin 的具体症状也不是其他人描述的那样（logout 时提示输入用户名和密码），就是点了没效果，仍在管理界面（还有人说启用 http basic auth login 的话就是无法 logout 的，只能关闭浏览器才 logout，这纯属无稽之谈）。

    我一直认为是 phpMyAdmin 或 mysql 设置出问题的，根本没往 php session save path 是否可写这方面想，我想当然地以为如果 php session save path 不可写，在 php 里启用 session 就会出错，别想进入 phpMyAdmin。

  • Reboot is still the best remedy in Linux

    Long time ago, I read an article about moving from Windows to Linux, the top differences a system administrator should keep in mind. I still remember one of the difference is reboot in Linux does not cure the problem as it does for Windows in 99% occasions.

    However, today I tried to fix a problem after I manually compiled php 5.2.9 (phpMyAdmin stop working, server response 500 error). I lack of knowledge of configure, make install, so I decided to remove php 5.2.9 and reverse to php 5.2.6 came with Fedora. I like yum install. Yum make my life so easy and it can also install packages perfect for me.

    php 5.2.9 executables was installed to /usr/local/bin (as php’s default), but php 5.2.6 was installed to /usr/bin (as fedora yum default). After I yum reinstalled php 5.2.6, I found

    If I typed “php-cgi -v”, Fedora could find php-cgi in /usr/bin
    If I typed “php -v”, Fedora still looked for php in /usr/local/bin

    I did not know why Fedora behave so strangely. After hours trying to correct Fedora mis-behavior without success, I reboot Fedora hopelessly. Then what? Fedora now is willing to load php executable in /usr/bin.

  • Install php-fpm on Fedora

    Use fedora yum install to install php is very easy. But, there is no yum install available to install php-fpm. I have to download php source and compile it from source.

    I do not know why Fedora configures its php this way, but it works fine for me. So I want to configure my php source the same way as Fedora did. I only add –enable-fpm to the configure.

    ./configure --build=i386-redhat-linux-gnu --host=i386-redhat-linux-gnu --target=i386-redhat-linux-gnu --program-prefix= --prefix=/usr --exec-prefix=/usr --bindir=/usr/bin --sbindir=/usr/sbin --sysconfdir=/etc --datadir=/usr/share --includedir=/usr/include --libdir=/usr/lib --libexecdir=/usr/libexec --localstatedir=/var --sharedstatedir=/usr/com --mandir=/usr/share/man --infodir=/usr/share/info --cache-file=../config.cache --with-libdir=lib --with-config-file-path=/etc --with-config-file-scan-dir=/etc/php.d --disable-debug --with-pic --disable-rpath --without-pear --with-bz2 --with-curl --with-exec-dir=/usr/bin --with-freetype-dir=/usr --with-png-dir=/usr --with-xpm-dir=/usr --enable-gd-native-ttf --with-t1lib=/usr --without-gdbm --with-gettext --with-gmp --with-iconv --with-jpeg-dir=/usr --with-openssl --with-png --with-expat-dir=/usr --with-pcre-regex=/usr --with-zlib --with-layout=GNU --enable-exif --enable-ftp --enable-magic-quotes --enable-sockets --enable-sysvsem --enable-sysvshm --enable-sysvmsg --enable-track-vars --enable-trans-sid --enable-yp --enable-wddx --with-kerberos --enable-ucd-snmp-hack --with-unixODBC=shared,/usr --enable-memory-limit --enable-shmop --enable-calendar --enable-dbx --enable-dio --without-mime-magic --without-sqlite --with-libxml-dir=/usr --with-xml --with-system-tzdata --enable-force-cgi-redirect --enable-pcntl --with-imap=shared --with-imap-ssl --enable-mbstring=shared --enable-mbstr-enc-trans --enable-mbregex --with-ncurses=shared --with-gd=shared --enable-bcmath=shared --enable-dba=shared --with-db4=/usr --with-xmlrpc=shared --with-ldap=shared --with-ldap-sasl --with-mysql=shared,/usr --with-mysqli=shared,/usr/bin/mysql_config --enable-dom=shared --with-dom-xslt=/usr --with-dom-exslt=/usr --with-pgsql=shared --with-snmp=shared,/usr --enable-soap=shared --with-xsl=shared,/usr --enable-xmlreader=shared --enable-xmlwriter=shared --enable-fastcgi --enable-fpm --enable-pdo=shared --with-pdo-odbc=shared,unixODBC,/usr --with-pdo-mysql=shared,/usr --with-pdo-pgsql=shared,/usr --with-pdo-sqlite=shared,/usr --enable-json=shared --enable-zip=shared --with-readline --enable-dbase=shared --with-pspell=shared --with-mcrypt=shared,/usr --with-mhash=shared,/usr --with-tidy=shared,/usr --with-mssql=shared,/usr

    I had several errors when run ./configure

    checking for BZip2 in default path… not found
    configure: error: Please reinstall the BZip2 distribution
    solution: yum install bzip-devel bzip-libs

    configure: error: DBA: Could not find necessary header file(s).
    solution: yum install gdbm-devel
    Well, someone suggests that, I did that, but error still exists. Then under my own decision, I run
    yum install php-dba
    Error still exists.
    yum install qdbm*
    Error still exists.
    yum install db4*
    Pass!

    configure: error: libjpeg.(a|so) not found.
    solution: yum install libjpeg libjpeg-devel

    Configure: error: libpng.(also) not found.
    solution: yum install libpng libpng-devel

    configure: error: libXpm.(a|so) not found.
    solution: yum install libXpm*

    Configure: error: freetype.h not found.
    solution: yum install freetype-devel

    configure: error: Unable to locate gmp.h
    solution: yum install mysql-devel

    configure: error: utf8_mime2text() has new signature, but U8T_CANONICAL is missing. This should not happen. Check config.log for additional information.
    solution: yum install libc-client-devel

    configure: error: Cannot find ldap.h
    solution: yum install openldap-devel

    configure: error: mcrypt.h not found. Please reinstall libmcrypt.
    solution: yum install libmcrypt-devel

    configure: error: Please reinstall libmhash – I cannot find mhash.h
    solution: yum install mhash-devel

    configure: error: Directory /usr is not a FreeTDS installation directory
    solution: yum install freetds-devel

    Configure: error: Please reinstall the ncurses distribution
    solution: yum install ncurses-devel

    checking for unixODBC support… configure: error: ODBC header file ‘/usr/include/sqlext.h’ not found!
    solution: yum install unixODBC-devel

    configure: error: Cannot find libpq-fe.h. Please specify correct PostgreSQL installation path
    solution: yum install postgresql-devel

    configure: error: Please reinstall the sqlite3 distribution
    solution: yun install sqlite-devel

    Configure: error: Cannot find pspell
    solution: yum install pspell-devel

    configure: error: Please reinstall readline – I cannot find readline.h
    solution: yum install readline-devel

    configure: error: SNMP sanity check failed. Please check config.log for more information.
    solution: yum install net-snmp-devel

    configure: error: Cannot find libtidy
    solution: yum install libtidy-devel

    configure: error: xslt-config not found. Please reinstall the libxslt >= 1.1.0 distribution
    solution: yum install libxslt-devel

  • Create a password file for Nginx basic authentication

    It is really a hard time for me to find a way to create a password file for Nginx basic authentication, because I did not realise htpasswd crpty is not available on Windows.

    Nginx documentation only mentions Use crypt(3) encryption for passwords, so I tried so hard with htpasswd.exe but could not generate a file recognised by Nginx. Hours later I found Apache documentation mentions -d is

    the default on all platforms but Windows, Netware and TPF. Though possibly supported by htpasswd on all platforms, it is not supported by the httpd server on Windows, Netware and TPF.

    I have two things to blame –

    1. I still use Windows to do my everyday work. If my first choice was htpasswd on Linux even without furthur instructions, it would have save me a lot of time.
    2. Nginx documentionation. If Nginx documentation is as good as Apache’s, Nginx may overwhelm the world.

  • Magento Skip Base URL validation before next step

    终于明白 Magento 在安装时问的一个问题是什么意思了：

    Skip Base URL validation before next step

    Check this box only if it is not possible to automatically validate Base URL. 

    如果给 Magento 指定一个 Base Url 在 internet 上不可解析，比如在开发阶段使用一个 Base Url 只在本机或内网内访问，则必须跳过 Base Url validation。

  • Perfect settings for Magento on Nginx

    Nginx 的文档不够详细，挺折腾人的。我经过两天181次黑匣试验，终于敢说入了 Nginx 的门。摸清 Nginx 的思路以后，才体会到它的先进性（不仅是效率上的）。php 和 nginx 搭配使用，感觉就不那么草根了，更容易借鉴 python 的 web infrastructure.

    从 Apache 到 Ngnix，不容易啊。难就难在要抛弃 Apache 的思维，其实同样的配置在 Nginx 总能做到的，而且更简洁。在Apache 下，我用 symbolic link 实现 Magento 和 WordPress 等一次安装多处使用，当时我认为已经是很简单的解决方案了；转移到 Nginx 平台，多处使用连 symblic link 也省了。

    以下是 Magento on Nginx 的配置，perfect，可以以不变应万变，目前我挺得意的。别笑我，这么几行配置，折腾我两天。

    location / {

root  $php_doc_root;

index  index.php;

if ($uri ~ ^/(media|js|skin)/) {

break;

}

if (!-e $request_filename) {

rewrite .* /index.php last;

}

}

location ~ ^/(app|lib|var)/ {

deny all;

}

location ~ ^/report/.*\.xml {

deny all;

}

location ~* ^.+\.(jpg|jpeg|gif|css|png|js|ico)$ {

root  $php_doc_root;

index  index.php;

access_log        off;

expires           30d;

}