此问题困扰我好几天了，起初以为是服务器配置问题，网上搜了很多解决方法都不行，今天叫其他同事测试都没问题，后来问了另一个朋友，告知win不同于linux和osx，linux和osx连接服务器ssh xx.xx.xx.xx相当于 ssh username@xx.xx.xx.xx，隐藏了用户名，而win系统直接就是 ssh xx.xx.xx.xx，所以我电脑的用户名和服务器的用户名不匹配，导致了服务器之间连接提示如下错误：
Permission denied (publickey,gssapi-with-mic).
知道问题的原因就好办了，我使用的是SecureCRT软件，点击Options>Global Options>SSH2,勾选Enable OpenSSH agent forwarding。保存退出软件，重新连接服务器就ok了。特意看了下同事的windows下的SecureCRT默认就是勾选这个的，mac的不是。。。
想弄个计划任务，用crontab -e编辑完之后会提示
crontab: “/usr/bin/vi” exited with status 1
是VI的问题，比较简单的解决办法是直接执行
嘟嘟鱼EDITOR=vim crontab -e
然后按i插入数据，保存退出即可，下次编辑直接用crontab -e
就可以了。| :e filename | Open filename for edition |
| :w | Save file |
| :q | Exit Vim |
| :q! | Quit without saving |
| :x | Write file (if changes has been made) and exit |
| :sav filename | Saves file as filename |
| . | Repeats the last change made in normal mode |
| 5. | Repeats 5 times the last change made in normal mode |
| k or Up Arrow | move the cursor up one line |
| j or Down Arrow | move the cursor down one line |
| e | move the cursor to the end of the word |
| b | move the cursor to the begining of the word |
| 0 | move the cursor to the begining of the line |
| G | move the cursor to the end of the file |
| gg | move the cursor to the begining of the file |
| L | move the cursor to the bottom of the screen |
| :59 | move cursor to line 59. Replace 59 by the desired line number. |
| 20| | move cursor to column 20. |
| % | Move cursor to matching parenthesis |
| [[ | Jump to function start |
| [{ | Jump to block start |
| y | Copy the selected text to clipboard |
| p | Paste clipboard contents |
| dd | Cut current line |
| yy | Copy current line |
| y$ | Copy to end of line |
| D | Cut to end of line |
| /word | Search word from top to bottom |
| ?word | Search word from bottom to top |
| * | Search the word under cursor |
| /\cstring | Search STRING or string, case insensitive |
| /jo[ha]n | Search john or joan |
| /\< the | Search the, theatre or then |
| /the\> | Search the or breathe |
| /\< the\> | Search the |
| /\< ¦.\> | Search all words of 4 letters |
| /\/ | Search fred but not alfred or frederick |
| /fred\|joe | Search fred or joe |
| /\<\d\d\d\d\> | Search exactly 4 digits |
| /^\n\{3} | Find 3 empty lines |
| :bufdo /searchstr/ | Search in all open files |
| bufdo %s/something/somethingelse/g | Search something in all the open buffers and replace it with somethingelse |
| :%s/old/new/g | Replace all occurences of old by new in file |
| :%s/onward/forward/gi | Replace onward by forward, case unsensitive |
| :%s/old/new/gc | Replace all occurences with confirmation |
| :2,35s/old/new/g | Replace all occurences between lines 2 and 35 |
| :5,$s/old/new/g | Replace all occurences from line 5 to EOF |
| :%s/^/hello/g | Replace the begining of each line by hello |
| :%s/$/Harry/g | Replace the end of each line by Harry |
| :%s/onward/forward/gi | Replace onward by forward, case unsensitive |
| :%s/ *$//g | Delete all white spaces |
| :g/string/d | Delete all lines containing string |
| :v/string/d | Delete all lines containing which didn’t contain string |
| :s/Bill/Steve/ | Replace the first occurence of Bill by Steve in current line |
| :s/Bill/Steve/g | Replace Bill by Steve in current line |
| :%s/Bill/Steve/g | Replace Bill by Steve in all the file |
| :%s/^M//g | Delete DOS carriage returns (^M) |
| :%s/\r/\r/g | Transform DOS carriage returns in returns |
| :%s#<[^>]\+>##g | Delete HTML tags but keeps text |
| :%s/^\(.*\)\n\1$/\1/ | Delete lines which appears twice |
| Ctrl+a | Increment number under the cursor |
| Ctrl+x | Decrement number under cursor |
| ggVGg? | Change text to Rot13 |
| Vu | Lowercase line |
| VU | Uppercase line |
| g~~ | Invert case |
| vEU | Switch word to uppercase |
| vE~ | Modify word case |
| ggguG | Set all text to lowercase |
| gggUG | Set all text to uppercase |
| :set ignorecase | Ignore case in searches |
| :set smartcase | Ignore case in searches excepted if an uppercase letter is used |
| :%s/\<./\u&/g | Sets first letter of each word to uppercase |
| :%s/\<./\l&/g | Sets first letter of each word to lowercase |
| :%s/.*/\u& | Sets first letter of each line to uppercase |
| :%s/.*/\l& | Sets first letter of each line to lowercase |
| :1,10 w outfile | Saves lines 1 to 10 in outfile |
| :1,10 w >> outfile | Appends lines 1 to 10 to outfile |
| :r infile | Insert the content of infile |
| :23r infile | Insert the content of infile under line 23 |
| :e . | Open integrated file explorer |
| :Sex | Split window and open integrated file explorer |
| :Sex! | Same as :Sex but split window vertically |
| :browse e | Graphical file explorer |
| :ls | List buffers |
| :cd .. | Move to parent directory |
| :args | List files |
| :args *.php | Open file list |
| :grep expression *.php | Returns a list of .php files contening expression |
| gf | Open file name under cursor |
| :!pwd | Execute the pwd unix command, then returns to Vi |
| !!pwd | Execute the pwd unix command and insert output in file |
| :sh | Temporary returns to Unix |
| $exit | Retourns to Vi |
| :%!fmt | Align all lines |
| !}fmt | Align all lines at the current position |
| 5!!fmt | Align the next 5 lines |
| :tabnew | Creates a new tab |
| gt | Show next tab |
| :tabfirst | Show first tab |
| :tablast | Show last tab |
| :tabm n(position) | Rearrange tabs |
| :tabdo %s/foo/bar/g | Execute a command in all tabs |
| :tab ball | Puts all open files in tabs |
| :new abc.txt | Edit abc.txt in new window |
| :e filename | Edit filename in current window |
| :split filename | Split the window and open filename |
| ctrl-w up arrow | Puts cursor in top window |
| ctrl-w ctrl-w | Puts cursor in next window |
| ctrl-w_ | Maximize current window vertically |
| ctrl-w| | Maximize current window horizontally |
| ctrl-w= | Gives the same size to all windows |
| 10 ctrl-w+ | Add 10 lines to current window |
| :vsplit file | Split window vertically |
| :sview file | Same as :split in readonly mode |
| :hide | Close current window |
| :nly | Close all windows, excepted current |
| :b 2 | Open #2 in this window |
| Ctrl+n Ctrl+p (in insert mode) | Complete word |
| Ctrl+x Ctrl+l | Complete line |
| :set dictionary=dict | Define dict as a dictionnary |
| Ctrl+x Ctrl+k | Complete with dictionnary |
| m {a-z} | Marks current position as {a-z} |
| ‘ {a-z} | Move to position {a-z} |
| ” | Move to previous position |
| :ab mail mail@provider.org | Define mail as abbreviation of mail@provider.org |
| :set autoindent | Turn on auto-indent |
| :set smartindent | Turn on intelligent auto-indent |
| :set shiftwidth=4 | Defines 4 spaces as indent size |
| ctrl-t, ctrl-d | Indent/un-indent in insert mode |
| >> | Indent |
| << | Un-indent |
| =% | Indent the code between parenthesis |
| 1GVG= | Indent the whole file |
| :syntax on | Turn on syntax highlighting |
| :syntax off | Turn off syntax highlighting |
| :set syntax=perl | Force syntax highlighting |
刚才机房通知有未备案的域名解析到我们用户的服务器上，察看了下是nginx环境。
在服务器上执行
locate nginx.conf
命令可以找到安装路径
一般默认路径是
/usr/local/nginx/conf/nginx.conf
编辑此文件，在原有的server { 上面插入以下代码
server {
listen 80 default;
return 500;
}
保存，执行
/usr/local/nginx/sbin/nginx
重启nginx即可，如果重启报如下错误
nginx: [emerg] bind() to 0.0.0.0:80 failed (98: Address already in use)
则执行
killall -9 nginx
杀掉进程，重新重启nginx即可。
注释：
listen 80 default;
表示监听80端口，default参数表示这个是默认虚拟主机。
return 500;
就是返回500的提示。
比如别人通过ip或者未知域名访问你的网站的时候，你希望禁止显示任何有效内容，可以给他返回500，目前国内很多机房都要求网站主关闭空主机头，防止未备案的域名指向过来造成麻烦。
centos下使用如下命令手动同步服务器时间,出现“the NTP socket is in use, exiting”错误。造成该原因是系统ntpd服务器正在运行中，可以通过 ps aux | grep ntpd 查看，如果还是要手动同步时间，就必须先停止该服务，命令为:
service ntpd stop 然后手工执行自动对时，命令如下：
ntpdate ntp.fudan.edu.cn 或 ntpdate ntp.api.bz 或 ntpdate 210.72.145.44 即可。
刚用户反映服务器rar版本低,下了个4.0的运行提示
/lib/libc.so.6: version `GLIBC_2.7′ not found
升级了centos的glibc库
yum -y update glibc
问题依旧。用命令查看glibc库的信息
rpm -qi glibc
显示系统的glibc库版本为2.5
在CentOS中用更新命令到2.5已经是最新版本了，只好手动下载 glibc 2.7 的源码包编译安装更新：
地址：http://ftp.gnu.org/pub/gnu/glibc/glibc-2.7.tar.gz
cd /usr/local/src
wget http://ftp.gnu.org/pub/gnu/glibc/glibc-2.7.tar.gz
tar zxvf glibc-2.7.tar.gz
glibc-2.7/configure #执行configure命令时不能进到glibc-2.7文件夹里面，否则无法执行
cd glibc-2.7
make && make install
刚才同事分享的，这下方便多了。
http://sourceforge.net/projects/p7zip/
这里下载7z
make
make install
7za x test.zip
刚帮一个用户查看ftp操作日志，发现没有记录，就帮他设置了下,他用的是pure-ftpd，保存下方法:
1)建立文件/var/log/pureftpd.log
2)修改/etc/syslog.conf
1>在这行的cron.none后面添加 ;ftp.none 使ftp的日志信息成私有
*.info;mail.none;authpriv.none;cron.none /var/log/messages
为
*.info;mail.none;authpriv.none;cron.none;ftp.none /var/log/messages
2>在/etc/syslog.conf文件最后加上
#pureftp日志
ftp.* –/var/log/pureftpd.log
注意: 不要去掉/var前面的–号,否则日志会在/var/log/messages与/var/log/purefpd.log里各记录一份. 添加了–号,就只会记录在/var/log/purefptd.log内
3)使/etc/syslog.conf生效
[root@www log]# killall -HUP syslogd
到现在设置完毕,重启下pure-ftpd,现在在客户端登陆ftp试下
1。先在北大天网搜索一下socks5的安装包，发现一大堆，最新版本是socks5-v1.0r11.tar.gz，于是下载到我的RH9的服务器上。
2。解压缩软件包
#tar xvfz socks5-v1.0r11.tar.gz
3.开始编译
#cd socks5-v1.0r11
#./configure –with-threads
#make
#make install
4.建立/etc/socks5.conf,其实在软件包里已经有现成的examples
#cd examples
#cp socks5.conf.singlehomed /etc/socks5.conf (我们挑选一个最简单的配置文件)
默认配置就是
# A Socks5 Config file for a normal, single homed server
permit – – – – – –
这个配置文件是允许任何人都可以使用这个socks5代理，并不需要验证 （更多…）
CentOS Linux 是一个依 GPL 规范,及利用 RedHat Enterprise Linux (RHEL) 的源代码 (source code) 来重新编译 (compile) 的 Linux 版本.
CentOS 提供和 RHEL 的 Binary 档案几乎百分之百兼容性,相同的版本 (Release) 和维护 (Maintainence) 更新时间.和 RedHat Enterprise Linux (RHEL) 不同的是,CentOS 依 GPL 的规范,移除了 RedHat 品牌及图片.
下载:CentOS 5.4
更新暂时未知