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路由上跑dnsmasq通过将客户端ip添加为edns ip转发到其它dns服务器时可以根据客户端ip做相应操作，dnmasq只有在设置add-subnet为固定ip段时才缓存，add-subnet=32时动态添加客户端ip为edns ip时不缓存，做了下修改可以缓存。

--- dnsmasq-2.86/src/edns0.c    2021-09-09 04:21:22.000000000 +0800
+++ dnsmasq-2.86-bak/src/edns0.c        2022-01-23 18:54:04.801336879 +0800
@@ -375,6 +375,7 @@
   if (cacheablep)
     *cacheablep = cacheable;
   
+  *cacheablep = 1;
   return len + 4;
 }
  
diff -urN dnsmasq-2.86/src/forward.c dnsmasq-2.86-bak/src/forward.c
--- dnsmasq-2.86/src/forward.c  2021-09-09 04:21:22.000000000 +0800
+++ dnsmasq-2.86-bak/src/forward.c      2022-01-23 18:58:25.020648204 +0800
@@ -596,7 +596,7 @@
       /* Get extended RCODE. */
       rcode |= sizep[2] << 4;
 
-      if (check_subnet && !check_source(header, plen, pheader, query_source))
+      if ( 0 && check_subnet && !check_source(header, plen, pheader, query_source))
        {
          my_syslog(LOG_WARNING, _("discarding DNS reply: subnet option mismatch"));
          return 0;

安装nginx依赖扩展，当typecho更新时调用http-cache-purge删除缓存，当命中缓存时调用lua清除set-cookie head，防止缓存的设置cookie header发送给所有人。

apt install libnginx-mod-http-cache-purge libnginx-mod-http-lua

http内添加：

    fastcgi_cache_path /dev/shm/fastcgi_cache_dir levels=1:2 keys_zone=phpcache:100m inactive=30d max_size=200M;
    fastcgi_temp_path /dev/shm/fastcgi_cache_dir/temp;
    fastcgi_cache_use_stale error timeout invalid_header http_500;
    fastcgi_ignore_headers Cache-Control Expires Set-Cookie;

修改server段：

  set $skip_cache 0;
  #跳过缓存，post请求
  if ($request_method = POST) {
    set $skip_cache 1;
  }
  #url包含参数
  if ($query_string != "") {
    set $skip_cache 1;
  }
  #指定url
  if ($request_uri ~* ^(/admin/|/action/|/search/|/feed/)) {
    set $skip_cache 1;
  }
  #登录用户
  if ($http_cookie ~* "typecho_authCode") {
    set $skip_cache 1;
  }
  #$uri经过重写后会改变，通过lua提前复制到$permalink
  set_by_lua_block $permalink {
    return ngx.var.uri
  }
  location ~ .*\.php$
  {
    try_files $uri =404;
    astcgi_pass  127.0.0.1:9000;
    fastcgi_index index.php;
    include fastcgi.conf;

    fastcgi_cache_key $scheme$request_method$host$permalink;
    add_header Cache-State $upstream_cache_status;
    fastcgi_cache_bypass $skip_cache;
    fastcgi_no_cache $skip_cache;
    fastcgi_cache phpcache;
    fastcgi_cache_valid 200 301 302 30d;

    log_by_lua_file "/etc/nginx/ngx_lua_reqstatus/hook.lua";
    header_filter_by_lua_block {
      --if ngx.status == ngx.HTTP_OK then
        --ngx.header['Cache-State'] = ngx.var.upstream_cache_status
      --end
      if ngx.var.upstream_cache_status == "HIT" then
        ngx.header['Set-Cookie'] = nil
      end
    }
  }

  location ~ /xxx/_clean_cache(/.*) {
      fastcgi_cache_purge phpcache "$scheme$request_method$host$1";
  }

typecho清除缓存插件：
https://github.com/typecho-fans/plugins/tree/master/Ncache
typecho默认在用户评论后会在cookie内设置用户名和邮箱信息，并在服务端读取cookie在html内写入相关信息，这样用户信息被缓存所有人都可以看到，可参考下面方法修改模板用js读取cookie内用户信息。
https://cuojue.org/read/typecho_comments_author_javascript.html

Flashcache是Facebook技术团队开发的一个内核模块，通过在文件系统（VFS）和设备驱动之间新增一次缓存层，可以用SSD作为介质的缓存，通过将传统硬盘上的热门数据缓存到SSD上，加速服务器磁盘读写性能。

Centos5.7下安装Flashcache，查看系统及内核版本：

uname -a
Linux master.www.haiyun.me 2.6.18-274.17.1.el5 #1 SMP Tue Jan 10 17:25:58 EST 2012 x86_64 x86_64 x86_64 GNU/Linux

cat /etc/issue
CentOS release 5.7 (Final)

下载安装内核源码树：

#https://www.haiyun.me
yum install rpm-build redhat-rpm-config unifdef
lftp -c "pget -n 10  http://vault.centos.org/5.7/os/SRPMS/kernel-2.6.18-274.el5.src.rpm"
rpm -i kernel-2.6.18-274.el5.src.rpm
cd /usr/src/redhat/SPECS/
rpmbuild -bp --target=$(uname -m) kernel.spec

内核模块编译准备：

cd /usr/src/redhat/BUILD/kernel-2.6.18/linux-2.6.18-274.*
make oldconfig
make prepare
make modules_prepare

下载编译Flashcache：

wget --no-check-certificate -O flashcache.tar.gz https://github.com/facebook/flashcache/tarball/master
tar zxvf flashcache.tar.gz 
cd facebook-flashcache-c4bddf6/
make install

加载Flashcache模块：

insmod /lib/modules/2.6.18-274.17.1.el5/extra/flashcache/flashcache.ko 
lsmod |grep flashcache
flashcache            112320  0 
dm_mod                102289  12 flashcache,dm_multipath,dm_raid45,dm_snapshot,dm_zero,dm_mirror,dm_log

创建Flashcache卷：

flashcache_create [-v] [-p back|thru|around] [-b block size] [-m md block size] [-s cache size] [-a associativity] cachedev ssd_devname disk_devname

挂载Flashcache卷：

mount /dev/mapper/cachedev  /home/wwwroot/