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

- **ID:** `networking/dhcp-ip-conflict`
- **领域:** networking
- **类别:** network_error
- **验证级别:** ai_generated
- **修复率:** 82%

## 根因

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。

## 版本兼容性

| 版本 | 状态 | 引入 | 弃用 |
|------|------|------|------|
| ISC DHCP 4.4.3-P1 | active | — | — |
| dnsmasq 2.89 | active | — | — |
| Windows Server 2022 DHCP | active | — | — |
| Linux dhcpcd 10.0.2 | active | — | — |

## 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

- **** — 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. (75% 失败率)
- **** — Longer leases make conflicts persist longer and do not address the root cause of overlapping addresses. (65% 失败率)
- **** — This hides the problem but allows duplicate IPs to be assigned, leading to intermittent connectivity issues and ARP conflicts. (90% 失败率)