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<text class="text-title" y="45" x="40">图 1.5：NAT3 联机受限一步步排查解决流程</text>
<text class="text-subtitle" y="70" x="40">逻辑排查步骤：光猫 Mode → 主路由设置 → Flow Offload 校验</text>
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<text class="text-header" y="135" x="80">步骤 1：检查 WAN 口公网 IP 状态</text>
<text class="text-body" y="155" x="80">确认路由器 WAN 口 IP 是否为公网 IP（排除 10.x, 100.64.x 内网段，若为 CGNAT 需联系运营商申请公网/IPv6）</text>
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<text class="text-header" y="225" x="80">步骤 2：消除“双重 NAT” (Double NAT)</text>
<text class="text-body" y="245" x="80">将光猫修改为“桥接模式 (Bridge)”，由主路由器进行 PPPoE 拨号，避免光猫+路由器两层 NAT 转换</text>
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<text class="text-header" y="315" x="80">步骤 3：开启 UPnP / NAT-PMP 自动映射</text>
<text class="text-body" y="335" x="80">在路由器设置中启用 UPnP，允许主机/游戏设备自动向路由器申请动态端口入站权限</text>
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<text class="text-header" y="405" x="80">步骤 4：调整 NAT 映射类型为 Full Cone</text>
<text class="text-body" y="425" x="80">若为 OpenWrt 固件，可选择开启 xt_FULLCONENAT / FullCone 驱动补丁，强制转换为 EIM/EIF 行为</text>
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<text class="text-header" y="495" x="80">步骤 5：验证 HNAT (硬件加速) 是否冲突</text>
<text class="text-body" y="515" x="80">若开启 FullCone 后测试依然为 NAT3，尝试临时关闭 HNAT/硬件加速，重新用 NatTypeTester 测试</text>
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<text fill="#6ee7b7" class="text-body" y="580" x="350">🎯 测试升级为 NAT2 / Full Cone，顺利组队！</text>
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