495884965

http://www.pc-freak.net/blog/how-to-find-out-all-programs-bandwidth-use-with-nethogs-top-like-utility-on-linux/
Nethog

Curl可以透過檢查Etag
來確認檔案是否修改過
如果沒有則回應304
# curl -I http://192.168.1.168/image/A.jpg
HTTP/1.1 200 OK
Date: Fri, 14 Nov 2014 01:37:28 GMT
Server: Apache/2.2.22 (Ubuntu)
Last-Modified: Wed, 12 Nov 2014 02:35:31 GMT
ETag: "5a-4213-507a03fda82c0"
Accept-Ranges: bytes
Content-Length: 16915
Content-Type: image/jpeg
# curl -I http://192.168.1.168/image/A.jpg --header 'If-None-Match: "5a-4213-507a03fda82c0"'
HTTP/1.1 304 Not Modified
Date: Fri, 14 Nov 2014 01:38:29 GMT
Server: Apache/2.2.22 (Ubuntu)
ETag: "5a-4213-507a03fda82c0"
http://wpcertification.blogspot.tw/2010/08/how-to-enable-etag-in-apache-http.html
Etag在Apache上是由Inode + mtime + Size來產生的
Curl也可以檢查Last-Modified
來確認檔案是否修改過
#curl -I http://192.168.1.168/image/A.jpg -H 'If-Modified-Since: Wed, 12 Nov 2014 02:35:31 GMT'
HTTP/1.1 304 Not Modified
Date: Fri, 14 Nov 2014 01:44:06 GMT
Server: Apache/2.2.22 (Ubuntu)
ETag: "5a-4213-507a03fda82c0"

http://www.chriscalender.com/troubleshooting-waiting-for-table-metadata-lock-errors-for-both-myisam-and-innodb-tables/
http://www.chriscalender.com/tag/waiting-for-table-metadata-lock/
#show (full)  processlist;
會有出現"Waiting for table metadata lock"的Process
 找出停留最久的把他kill
#kill  [porcess id];
建議把
wait_timeout 和 interactive_timeout秒數調低一點
ex: 60秒
#show ENGINE INNODB STATUS;

http://lincolnloop.com/blog/tracking-application-response-time-nginx/
https://www.digitalocean.com/community/tutorials/how-to-configure-nginx-as-a-reverse-proxy-for-apache
#vi /etc/nginx/sites-available/default
location / {
    proxy_set_header X-Real-IP $remote_addr;
    proxy_set_header X-Forwarded-For $remote_addr;
    proxy_set_header Host $host;
    proxy_pass http://192.168.1.168;
}

http://weizhifeng.net/nginx-proxy-cache.html
很棒的解說
Nginx效能解析
以apache為後端，Nginx為前端
Nginx將頁面圖片cache在本機來回應
#vi /etc/nginx/sites-available/default
server {
   :
   :
   location / {
     # First attempt to serve request as file, then
     # as directory, then fall back to index.html
     #try_files $uri $uri/ /index.html;
     # Uncomment to enable naxsi on this location
     # include /etc/nginx/naxsi.rules
     proxy_set_header X-Real-IP $remote_addr;
     proxy_set_header X-Forwarded-For $remote_addr;
     proxy_set_header Host $host;
     proxy_pass http://192.168.1.168;
     proxy_cache tmpcache;
     proxy_cache_key "$scheme$request_method$host$request_uri";
     proxy_cache_valid 200 304 1m;
     //後端回應http_status_code 200和304的
     //保留一分鐘
     proxy_cache_use_stale error timeout invalid_header updating http_500 http_502 http_503 http_504 http_404;
     //後端出問題時，以cache資料回應
     #proxy_cache_revalidate on;
     }
   :
   :
}
#vi /etc/nginx/nginx.conf
http {
   :
   :
     ##
     # page cache
     ##
     proxy_cache_path /tmp/nginx/cache levels=1:2 keys_zone=tmpcache:5m max_size=100m;
     #proxy_temp_path /tmp/nginx/tmp 1 2; #option
     include /etc/nginx/conf.d/*.conf;
     include /etc/nginx/sites-enabled/*;
}
#mkdir -p /tmp/nginx/cache
#mkdir -p /tmp/nginx/tmp
#service nginx restart
可以去比較前端Nginx與後端Apache的access.log
 

http://lincolnloop.com/blog/tracking-application-response-time-nginx/
https://www.digitalocean.com/community/tutorials/how-to-configure-nginx-as-a-reverse-proxy-for-apache
#vi /etc/nginx/sites-available/default
location / {
    proxy_set_header X-Real-IP $remote_addr;
    proxy_set_header X-Forwarded-For $remote_addr;
    proxy_set_header Host $host;
    proxy_pass http://192.168.1.168;
}

#crontab -e
30 20 8-14,22-28 * * test $(date +%u) -eq 1 && /usr/local/bin/backup.sh >> /var/log/backup.log 2>&1
date +%u ：顯示一週的第幾天

@Echo Off
echo | set /p=網路連現中.
:CheckNet
echo | set /p=.
ping -n 1 -w 1000 192.168.1.235 |find /I "Reply"
If %Errorlevel%==1 goto CheckNet
echo 1

How to check if SSL v2 is enabled using openssl
http://www.aip.im/2012/04/how-to-check-if-ssl-v2-is-enabled-using-openssl/
OpenSSL Command-Line HOWTO
https://www.madboa.com/geek/openssl/#intro-version
openssl 指令 command line
http://ssorc.tw/42
線上檢查網頁SSL版本
http://foundeo.com/products/iis-weak-ssl-ciphers/
SSL Server Test  ( 含漏洞檢查 )
https://www.ssllabs.com/ssltest/index.html
SSL原理
http://www.techbang.com/posts/17664-apple-out-of-the-package-whether-your-ssl-encrypted-security-ssl-theory-analysis-security-cryptography-see-encryption-technologies-computer-king-117-special-report-of-may
# echo -e "HEAD /index.html HTTP/1.0\r\nHost: www.yahoo.com\r\n\r\n" | openssl s_client -ssl2 -msg -connect www.example.com:443

#vi ~/.vimrc
set tabstop=4 shiftwidth=4 softtabstop=4 expandtab
將tab值設定為4個空白
非在4個倍數的會自動調整
syntax on
http://www.vim.org/scripts/script_search_results.php
到此搜尋(最下方)下載wombat256.vim到~/.vim/colors/
#vi ~/.vimrc
colorscheme wombat256
set t_Co=256
搜尋python.vim下載到~/.vim/syntax/
#vi ~/.vimrc
let python_highlight_all = 1
set hlsearch
set incsearch
set ignorecase