networking network_error ai_generated true

DHCP：检测到IP地址192.168.1.50与MAC 00:11:22:33:44:55冲突

DHCP: IP address 192.168.1.50 conflict detected with MAC 00:11:22:33:44:55

ID: networking/dhcp-ip-conflict

其他格式: JSON · Markdown 中文 · English
82%修复率
88%置信度
1证据数
2023-08-10首次发现

版本兼容性

版本状态引入弃用备注
ISC DHCP 4.4.3-P1 active — — —
dnsmasq 2.89 active — — —
Windows Server 2022 DHCP active — — —
Linux dhcpcd 10.0.2 active — — —

根因分析

DHCP服务器检测到提供的IP地址已被网络上的另一台主机使用，通常是由于静态IP分配与DHCP池重叠或存在恶意DHCP服务器。

English

A DHCP server has detected that an offered IP address is already in use by another host on the network, typically due to a static IP assignment overlapping with the DHCP pool or a rogue DHCP server.

generic

官方文档

https://kb.isc.org/docs/aa-00798

解决方案

  1. Exclude the conflicting IP from the DHCP pool and assign it as a static reservation: `dhcpd.conf: range 192.168.1.100 192.168.1.200; host static-host { hardware ethernet 00:11:22:33:44:55; fixed-address 192.168.1.50; }`
  2. Run `arp -d 192.168.1.50` on the DHCP server to clear the ARP cache, then force the client to renew: `dhclient -r && dhclient`

无效尝试

常见但无效的做法:

  1. 75% 失败

    The conflicting IP is still in the pool and may be reassigned, causing the same conflict again unless the pool or static assignment is fixed.

  2. 65% 失败

    Longer leases make conflicts persist longer and do not address the root cause of overlapping addresses.

  3. 90% 失败

    This hides the problem but allows duplicate IPs to be assigned, leading to intermittent connectivity issues and ARP conflicts.