messages中的DHCP请求过多：DHCPINFORM，DHCPACK和DHCPREQUEST重复

我有一个为几个子网运行DHCP的CentOS 5系统。在/ var / log / messages中，我看到了不断的DHCPINFORM，DHCPACK和DHCPREQUEST消息。我不明白为什么这些请求在这里比其他的安装更频繁。这些消息每隔几秒就会爆发一次，导致极大的日志文件。

这里的大部分设备都是无线手持设备（使用Windows CE TCP协议栈）。我会很感激任何消息，以消除不断的消息。

/etc/dhcpd.conf中

default-lease-time 28800; authoritative; allow bootp; ddns-update-style none; option subnet-mask 255.255.255.0; option domain-name-servers 10.1.1.3; option domain-name "xxxinc.com"; option tftp-server-name "10.1.1.3"; option ntp-servers 17.151.16.21; subnet 10.1.1.0 netmask 255.255.255.0 { range dynamic-bootp 10.1.1.120 10.1.1.211; option tftp-server-name "10.1.1.3"; next-server 10.1.1.3; filename "/dsl/pxelinux.0"; option routers 10.1.1.1; } subnet 10.1.2.0 netmask 255.255.255.0 { range dynamic-bootp 10.1.2.130 10.1.2.199; option tftp-server-name "10.1.1.3"; next-server 10.1.1.3; filename "/dsl/pxelinux.0"; option routers 10.1.2.1; }

在/ var / log / messages中

 Apr 4 10:59:44 General dhcpd: DHCPINFORM from 10.1.1.136 via eth0 Apr 4 10:59:44 General dhcpd: DHCPACK to 10.1.1.136 (00:16:35:07:1e:61) via eth0 Apr 4 10:59:44 General dhcpd: DHCPINFORM from 10.1.1.136 via eth0 Apr 4 10:59:44 General dhcpd: DHCPACK to 10.1.1.136 (00:16:35:07:1e:61) via eth0 Apr 4 10:59:44 General dhcpd: DHCPINFORM from 10.1.1.136 via 10.1.1.254 Apr 4 10:59:44 General dhcpd: DHCPACK to 10.1.1.136 (00:16:35:07:1e:61) via eth0 Apr 4 10:59:44 General dhcpd: DHCPINFORM from 10.1.1.136 via 10.1.1.254 Apr 4 10:59:44 General dhcpd: DHCPACK to 10.1.1.136 (00:16:35:07:1e:61) via eth0 Apr 4 10:59:44 General dhcpd: DHCPINFORM from 10.1.1.136 via 10.1.1.2 Apr 4 10:59:44 General dhcpd: DHCPACK to 10.1.1.136 (00:16:35:07:1e:61) via eth0 Apr 4 10:59:46 General dhcpd: DHCPREQUEST for 10.1.1.137 from 00:15:70:85:9b:ea via eth0 Apr 4 10:59:46 General dhcpd: DHCPACK on 10.1.1.137 to 00:15:70:85:9b:ea via eth0 Apr 4 10:59:46 General dhcpd: DHCPREQUEST for 10.1.1.137 from 00:15:70:85:9b:ea via eth0 Apr 4 10:59:46 General dhcpd: DHCPACK on 10.1.1.137 to 00:15:70:85:9b:ea via eth0 Apr 4 10:59:46 General dhcpd: DHCPREQUEST for 10.1.1.137 from 00:15:70:85:9b:ea via 10.1.1.254 Apr 4 10:59:46 General dhcpd: DHCPACK on 10.1.1.137 to 00:15:70:85:9b:ea via 10.1.1.254 Apr 4 10:59:46 General dhcpd: DHCPREQUEST for 10.1.1.137 from 00:15:70:85:9b:ea via 10.1.1.254 Apr 4 10:59:46 General dhcpd: DHCPACK on 10.1.1.137 to 00:15:70:85:9b:ea via 10.1.1.254 Apr 4 10:59:46 General dhcpd: DHCPREQUEST for 10.1.1.137 from 00:15:70:85:9b:ea via 10.1.1.2 Apr 4 10:59:46 General dhcpd: DHCPACK on 10.1.1.137 to 00:15:70:85:9b:ea via 10.1.1.2 Apr 4 10:59:47 General dhcpd: DHCPINFORM from 10.1.2.193 via 10.1.2.1 Apr 4 10:59:47 General dhcpd: DHCPACK to 10.1.2.193 (00:1a:4b:c0:e0:a4) via eth0 Apr 4 10:59:47 General dhcpd: DHCPINFORM from 10.1.1.147 via eth0 Apr 4 10:59:47 General dhcpd: DHCPACK to 10.1.1.147 (00:19:bb:d3:bc:e8) via eth0 Apr 4 10:59:47 General dhcpd: DHCPINFORM from 10.1.1.147 via eth0 Apr 4 10:59:47 General dhcpd: DHCPACK to 10.1.1.147 (00:19:bb:d3:bc:e8) via eth0 Apr 4 10:59:47 General dhcpd: DHCPINFORM from 10.1.1.147 via 10.1.1.254 Apr 4 10:59:47 General dhcpd: DHCPACK to 10.1.1.147 (00:19:bb:d3:bc:e8) via eth0 Apr 4 10:59:47 General dhcpd: DHCPINFORM from 10.1.1.147 via 10.1.1.254 Apr 4 10:59:47 General dhcpd: DHCPACK to 10.1.1.147 (00:19:bb:d3:bc:e8) via eth0 Apr 4 10:59:47 General dhcpd: DHCPINFORM from 10.1.1.147 via 10.1.1.2 Apr 4 10:59:47 General dhcpd: DHCPACK to 10.1.1.147 (00:19:bb:d3:bc:e8) via eth0 Apr 4 10:59:49 General dhcpd: DHCPREQUEST for 10.1.1.198 from 00:15:70:86:dc:b9 via eth0 Apr 4 10:59:49 General dhcpd: DHCPACK on 10.1.1.198 to 00:15:70:86:dc:b9 via eth0 Apr 4 10:59:49 General dhcpd: DHCPREQUEST for 10.1.1.198 from 00:15:70:86:dc:b9 via eth0 Apr 4 10:59:49 General dhcpd: DHCPACK on 10.1.1.198 to 00:15:70:86:dc:b9 via eth0 Apr 4 10:59:49 General dhcpd: DHCPREQUEST for 10.1.1.198 from 00:15:70:86:dc:b9 via 10.1.1.254 Apr 4 10:59:49 General dhcpd: DHCPACK on 10.1.1.198 to 00:15:70:86:dc:b9 via 10.1.1.254 Apr 4 10:59:49 General dhcpd: DHCPREQUEST for 10.1.1.198 from 00:15:70:86:dc:b9 via 10.1.1.254 Apr 4 10:59:49 General dhcpd: DHCPACK on 10.1.1.198 to 00:15:70:86:dc:b9 via 10.1.1.254 Apr 4 10:59:49 General dhcpd: DHCPREQUEST for 10.1.1.198 from 00:15:70:86:dc:b9 via 10.1.1.2 Apr 4 10:59:49 General dhcpd: DHCPACK on 10.1.1.198 to 00:15:70:86:dc:b9 via 10.1.1.2

UPDATE

我从一些DHCP服务器端路由器中删除了一些无关的ip helper-address条目。大部分的stream量已经平息，但是我仍然得到很多DHCPINFORM，DHCPACK …

 Oct 26 17:22:23 General dhcpd: DHCPINFORM from 10.1.1.140 via eth0 Oct 26 17:22:23 General dhcpd: DHCPACK to 10.1.1.140 (00:16:35:07:1e:2c) via eth0 Oct 26 17:22:27 General dhcpd: DHCPINFORM from 10.1.1.147 via eth0 Oct 26 17:22:27 General dhcpd: DHCPACK to 10.1.1.147 (00:19:bb:d3:bc:e8) via eth0 Oct 26 17:22:27 General dhcpd: DHCPINFORM from 10.1.1.140 via eth0 Oct 26 17:22:27 General dhcpd: DHCPACK to 10.1.1.140 (00:16:35:07:1e:2c) via eth0 Oct 26 17:22:39 General dhcpd: DHCPINFORM from 10.1.1.182 via eth0 Oct 26 17:22:39 General dhcpd: DHCPACK to 10.1.1.182 (00:19:bb:d3:ec:f1) via eth0 Oct 26 17:22:43 General dhcpd: DHCPINFORM from 10.1.1.182 via eth0 Oct 26 17:22:43 General dhcpd: DHCPACK to 10.1.1.182 (00:19:bb:d3:ec:f1) via eth0 Oct 26 17:22:49 General dhcpd: DHCPINFORM from 10.1.2.198 via 10.1.2.1 Oct 26 17:22:49 General dhcpd: DHCPACK to 10.1.2.198 (00:1e:0b:79:e5:15) via eth0 Oct 26 17:23:01 General dhcpd: DHCPINFORM from 10.1.1.194 via eth0 Oct 26 17:23:01 General dhcpd: DHCPACK to 10.1.1.194 (00:1e:0b:7b:2d:d6) via eth0 Oct 26 17:23:04 General dhcpd: DHCPINFORM from 10.1.1.136 via eth0 Oct 26 17:23:04 General dhcpd: DHCPACK to 10.1.1.136 (00:16:35:07:1e:61) via eth0 Oct 26 17:23:07 General dhcpd: DHCPINFORM from 10.1.1.136 via eth0 Oct 26 17:23:07 General dhcpd: DHCPACK to 10.1.1.136 (00:16:35:07:1e:61) via eth0 Oct 26 17:23:09 General dhcpd: DHCPINFORM from 10.1.2.193 via 10.1.2.1 Oct 26 17:23:09 General dhcpd: DHCPACK to 10.1.2.193 (00:1a:4b:c0:e0:a4) via eth0 Oct 26 17:23:12 General dhcpd: DHCPINFORM from 10.1.2.179 via 10.1.2.1 Oct 26 17:23:12 General dhcpd: DHCPACK to 10.1.2.179 (00:19:bb:d3:f6:26) via eth0 Oct 26 17:23:13 General dhcpd: DHCPINFORM from 10.1.2.193 via 10.1.2.1 Oct 26 17:23:13 General dhcpd: DHCPACK to 10.1.2.193 (00:1a:4b:c0:e0:a4) via eth0 Oct 26 17:23:15 General dhcpd: DHCPINFORM from 10.1.2.179 via 10.1.2.1 Oct 26 17:23:15 General dhcpd: DHCPACK to 10.1.2.179 (00:19:bb:d3:f6:26) via eth0 Oct 26 17:23:36 General dhcpd: DHCPINFORM from 10.1.1.140 via eth0 Oct 26 17:23:36 General dhcpd: DHCPACK to 10.1.1.140 (00:16:35:07:1e:2c) via eth0 Oct 26 17:23:37 General dhcpd: DHCPINFORM from 10.1.1.147 via eth0 Oct 26 17:23:37 General dhcpd: DHCPACK to 10.1.1.147 (00:19:bb:d3:bc:e8) via eth0 Oct 26 17:23:40 General dhcpd: DHCPINFORM from 10.1.1.140 via eth0 Oct 26 17:23:40 General dhcpd: DHCPACK to 10.1.1.140 (00:16:35:07:1e:2c) via eth0 Oct 26 17:23:41 General dhcpd: DHCPINFORM from 10.1.1.147 via eth0 Oct 26 17:23:41 General dhcpd: DHCPACK to 10.1.1.147 (00:19:bb:d3:bc:e8) via eth0 Oct 26 17:23:50 General dhcpd: DHCPINFORM from 10.1.2.198 via 10.1.2.1 Oct 26 17:23:50 General dhcpd: DHCPACK to 10.1.2.198 (00:1e:0b:79:e5:15) via eth0 Oct 26 17:23:51 General dhcpd: DHCPINFORM from 10.1.1.182 via eth0 Oct 26 17:23:51 General dhcpd: DHCPACK to 10.1.1.182 (00:19:bb:d3:ec:f1) via eth0

看起来你有客户端连接到多个子网（或互相转发DHCP HELPER的路由器）。由于我不知道你的拓扑，我不能肯定地说。

几件事情来检查：

这是否发生在所有客户端？或者只是位于特定网段的那些？
这些客户端是否连接到多个子网？
你是否证实你的子网之间没有桥接？

你应该看看你的每一个客户，也许用ethreal，并确定他们是否从多个路由器（他们可能是）接收多个DHCPACK。

如果在DHCPACK响应中没有指定WPAD选项，某些客户端（特别是Windows 7）会不断发送DHCPINFORM消息。

您可以通过将以下行添加到您的configuration来修复ISC DHCP：

 option wpad code 252 = text; subnet xxx { option wpad "\n"; }

您可以通过将以下内容添加到dnsmasq.conf文件中来解决这个问题：

 dhcp-option=252,"\n"

您的DHCP服务器似乎多次在同一接口上监听，使用不同的套接字（查看“via”位 – 它谈到eth0和两个不同的IP地址）。如果您明确configuration了DHCP服务器的侦听套接字，请检查每个接口只有一个套接字。

除此之外，交通看起来很正常。 Windows主机通常会使用DHCPINFORM查询他们没有caching的其他参数，而WinCE的caching也非常小。

如果你的机器上有“DHCP Manager”UI，你有没有试过增加dhcpd守护进程的详细程度？好奇，如果你从这个问题得到任何其他线索的问题。或者启用详细和事务日志启用：

 # /etc/init.d/dhcp stop # /usr/lib/inet/in.dhcpd -v -l 5 [options]

其中/etc/syslog.conf包含：

 local0.notice /var/log/dhcpsrvc