在对使用 提供的图像进行测试时apache，我注意到创建新会话时：
Waiting (TTFB): 1.09s
Initial connection + SSL handshake: 370ms
DNS Lookup:165ms
但随后使用持久连接：
Waiting (TTFB): 187ms
Content Download:4ms
因此，我们发现TTFB新连接的平均时间是非持久连接的 5 倍。这是正常的吗？
附带问题：为什么只有在有新连接时才进行新的 DNS 查找？
我的电子邮件过去常常在标题中使用 DKIM 签名。现在，如果您检查电子邮件来源，它没有签名。
怎么了？我该如何调试，我可以查看哪些日志？
cat /etc/exim4/conf.d/main/00_local_macros
回报：
DKIM_CANON = relaxed
DKIM_SELECTOR = mail
DKIM_DOMAIN = ${sg{${lc:${domain:$h_from:}}}{^www\.}{}}
DKIM_FILE = /etc/exim4/keys/${dkim_domain}/mail.private
DKIM_PRIVATE_KEY = ${if exists{DKIM_FILE}{DKIM_FILE}{0}}
钥匙的位置：
ls -la /etc/exim4/keys/example.co.za/
回报：
-rwxr-x--- 1 Debian-exim Debian-exim 887 Mar 7 17:26 mail.private
-rwxr-x--- 1 Debian-exim Debian-exim 305 Mar 7 17:26 mail.txt
我正在查看我的 apache error.log，我注意到有一些尝试wp-config.php失败了。
奇怪的是，它说请求的是网站本身。
攻击者/机器人是如何做到这一点的？
这是日志[用示例替换实际网址]：
[Sun Mar 20 09:06:40 2016] [error] [client 105.228.84.134] PHP Fatal error: Call to undefined function _deprecated_file() in /var/www/example/wp-includes/rss-functions.php on line 8, referer: http://example.co.za/
[Sun Mar 20 09:06:41 2016] [error] [client 105.228.84.134] File does not exist: /var/www/example/wp-content/debug.log, referer: http://example.co.za/
[Sun Mar 20 09:06:42 2016] [error] [client 105.228.84.134] File does not exist: /var/www/example/wp-config.php~, referer: http://example.co.za/
[Sun Mar 20 09:06:42 2016] [error] [client 105.228.84.134] File does not exist: /var/www/example/#wp-config.php#, referer: http://example.co.za/
[Sun Mar 20 09:06:42 2016] [error] [client 105.228.84.134] File does not exist: /var/www/example/wp-config.php.save, referer: http://example.co.za/
[Sun Mar 20 09:06:44 2016] [error] [client 105.228.84.134] File does not exist: /var/www/example/wp-config.old, referer: http://example.co.za/
[Sun Mar 20 09:06:42 2016] [error] [client 105.228.84.134] File does not exist: /var/www/example/wp-config.php.swp, referer: http://example.co.za/
[Sun Mar 20 09:06:42 2016] [error] [client 105.228.84.134] File does not exist: /var/www/example/wp-config.php.swo, referer: http://example.co.za/
[Sun Mar 20 09:06:42 2016] [error] [client 105.228.84.134] File does not exist: /var/www/example/.wp-config.php.swp, referer: http://example.co.za/
[Sun Mar 20 09:06:42 2016] [error] [client 105.228.84.134] File does not exist: /var/www/example/wp-config.bak, referer: http://example.co.za/
[Sun Mar 20 09:06:42 2016] [error] [client 105.228.84.134] File does not exist: /var/www/example/wp-config.php_bak, referer: http://example.co.za/
[Sun Mar 20 09:06:42 2016] [error] [client 105.228.84.134] File does not exist: /var/www/example/wp-config.php.bak, referer: http://example.co.za/
[Sun Mar 20 09:06:44 2016] [error] [client 105.228.84.134] File does not exist: /var/www/example/wp-config.save, referer: http://example.co.za/
[Sun Mar 20 09:06:44 2016] [error] [client 105.228.84.134] File does not exist: /var/www/example/wp-config.php.old, referer: http://example.co.za/
[Sun Mar 20 09:06:45 2016] [error] [client 105.228.84.134] File does not exist: /var/www/example/wp-config.php.orig, referer: http://example.co.za/
[Sun Mar 20 09:06:45 2016] [error] [client 105.228.84.134] File does not exist: /var/www/example/wp-config.php.original, referer: http://example.co.za/
[Sun Mar 20 09:06:45 2016] [error] [client 105.228.84.134] File does not exist: /var/www/example/wp-config.orig, referer: http://example.co.za/
[Sun Mar 20 09:06:45 2016] [error] [client 105.228.84.134] File does not exist: /var/www/example/wp-config.original, referer: http://example.co.za/
[Sun Mar 20 09:06:47 2016] [error] [client 105.228.84.134] File does not exist: /var/www/example/wp-config.txt, referer: http://example.co.za/
我认为我不会使用 LDAP 进行身份验证。而且我不太确定每个包的作用。
zimbra-core
zimbra-ldap
zimbra-logger
zimbra-mta
zimbra-snmp
zimbra-store
zimbra-apache
zimbra-spell
zimbra-memcached
zimbra-proxy
我已经安装zimbra并使用它作为我的邮件服务器。但是我也想安装request tracker，以便服务器可以用于管理员，而我的其他服务器纯粹作为 Web 服务器。
Zimbra 工作 100%，但是当我安装httpd前端zimbra消失并被默认apache httpd页面取代。
我在用centOS 6 64 bit
试图卸载zarafa邮件服务器。
我yum list installed用来查看已经安装的包。
之后我使用yum erase zarafa*
它拿起所有的包裹，但返回：
Error in PREUN scriptlet in rpm package zarafa-dagent
Error in PREUN scriptlet in rpm package zarafa-gateway
Error in PREUN scriptlet in rpm package zarafa-monitor
Error in PREUN scriptlet in rpm package zarafa-server
Error in PREUN scriptlet in rpm package zarafa-spooler
Error in PREUN scriptlet in rpm package zarafa-ical
zarafa-ical-7.1.9-1.el6.i686 was supposed to be removed but is not!
Verifying : zarafa-ical-7.1.9-1.el6.i686 1/6
zarafa-spooler-7.1.9-1.el6.i686 was supposed to be removed but is not!
Verifying : zarafa-spooler-7.1.9-1.el6.i686 2/6
zarafa-server-7.1.9-1.el6.i686 was supposed to be removed but is not!
Verifying : zarafa-server-7.1.9-1.el6.i686 3/6
zarafa-monitor-7.1.9-1.el6.i686 was supposed to be removed but is not!
Verifying : zarafa-monitor-7.1.9-1.el6.i686 4/6
zarafa-gateway-7.1.9-1.el6.i686 was supposed to be removed but is not!
Verifying : zarafa-gateway-7.1.9-1.el6.i686 5/6
zarafa-dagent-7.1.9-1.el6.i686 was supposed to be removed but is not!
Verifying : zarafa-dagent-7.1.9-1.el6.i686 6/6
Failed:
zarafa-dagent.i686 0:7.1.9-1.el6 zarafa-gateway.i686 0:7.1.9-1.el6 zarafa-ical.i686 0:7.1.9-1.el6 zarafa-monitor.i686 0:7.1.9-1.el6 zarafa-server.i686 0:7.1.9-1.el6
zarafa-spooler.i686 0:7.1.9-1.el6
/etc/init.d/clamd start
错误：
[FAILED] log gives ERROR: daemonize() failed: Cannot Allocate Memory
上Cent OS
total Mem: 510876kb
/etc/init.d/clamd start
在/var/log/clamav
ERROR: daemonize() failed: Cannot Allocate Memory?
这是一个可以解决的问题吗？
我以为Clamd只需要20 - 40 mb
说Memory Free: 273844k
strace 的结果：
waitpid(-1, [{WIFEXITED(s) && WEXITSTATUS(s) == 1}], 0) = 1658
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
--- SIGCHLD (Child exited) @ 0 (0) ---
waitpid(-1, 0xbff84a2c, WNOHANG) = -1 ECHILD (No child processes)
sigreturn() = ? (mask now [])
rt_sigaction(SIGINT, {SIG_DFL, [], 0}, {0x80810f0, [], 0}, 8) = 0
rt_sigprocmask(SIG_BLOCK, NULL, [], 8) = 0
read(255, "", 1694) = 0
exit_group(1) = ?
strace -f 的结果：
strace -f -o /tmp/clamd.txt service clamd start
几乎相同，我在寻找某种错误吗？