Linux

/var/log/messages 中的 DHCP 請求過多：DHCPINFORM、DHCPACK 和 DHCPREQUEST 重複

  • April 5, 2017

我有一個為多個子網執行 DHCP 的 CentOS 5 系統。在 /var/log/messages 中，我看到不斷的 DHCPINFORM、DHCPACK 和 DHCPREQUEST 消息。我不明白為什麼這些請求在這裡比在其他安裝中更頻繁。消息每隔幾秒就會爆發一次，導致日誌文件非常大。

這裡的大部分設備是無線手持設備（使用 Windows CE TCP 堆棧）。對於平息不斷的消息，我將不勝感激。

/etc/dhcpd.conf

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;
}

/var/日誌/消息

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

更新

我已經ip helper-address從一些 DHCP 伺服器端路由器中刪除了一些無關的條目。大部分流量已經消退，但是我仍然收到很多 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

看起來您的客戶端連接到多個子網（或將 dhcp 幫助程序相互中繼的路由器）。由於我不了解您的拓撲結構，因此我不能肯定地說。

需要檢查的幾件事：

  1. 所有客戶都會出現這種情況嗎？或者只是位於特定網段的那些？
  2. 這些客戶端是否連接到多個子網？
  3. 您是否已確認子網之間沒有橋接？

您應該查看您的每個客戶端，可能使用 ethreal，並確定它們是否從多個路由器接收多個 DHCPACK（它們可能是）。

引用自：https://serverfault.com/questions/255487

相關問答

Linux

輪換由 DHCP 指定的 DNS 伺服器

  • August 7, 2015
檢視問答
Linux

如何覆蓋 DHCP 在 AWS 的 CentOS7 機器上配置的主機名？

  • November 26, 2014
檢視問答
Linux

DHCPD：向隨機節點和受讓人提供（兩次）永久租用 IP

  • January 20, 2014
檢視問答
Linux

從 ipv6 dhcp 伺服器獲取 IP

  • June 11, 2013
檢視問答
Linux

路由器交換後無法通過 DHCP 連接 CentOS 虛擬機

  • March 12, 2013
檢視問答
Linux

從客戶端電腦確定 DHCP 伺服器的 IP 地址

  • July 17, 2012
檢視問答