Ubuntu STA+AP 开机自启完整方案

Ubuntu STA+AP 开机自启完整方案

1. rfkill 自动解锁 WLAN

文件：/etc/systemd/system/unblock-wifi.service

[Unit]
Description=Unblock WiFi
Before=wlan-ap.service[Service]
Type=oneshot
ExecStart=/usr/sbin/rfkill unblock all
RemainAfterExit=yes[Install]
WantedBy=multi-user.target

启用：

sudo systemctl daemon-reload
sudo systemctl enable unblock-wifi.service

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2. 创建虚拟 AP 接口

文件：/etc/systemd/system/wlan-ap.service

[Unit]
Description=Create virtual AP interface
After=unblock-wifi.service
Requires=unblock-wifi.service[Service]
Type=oneshot
# 创建虚拟接口
ExecStart=/sbin/iw dev wlp3s0 interface add wlp3s0_ap type __ap
# 给接口分配静态 IP
ExecStartPost=/sbin/ip addr add 192.168.50.1/24 dev wlp3s0_ap
ExecStartPost=/sbin/ip link set dev wlp3s0_ap up
RemainAfterExit=yes[Install]
WantedBy=multi-user.target

启用：

sudo systemctl daemon-reload
sudo systemctl enable wlan-ap.service

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3. hostapd AP 服务

文件：/etc/systemd/system/hostapd-ap.service

[Unit]
Description=Start hostapd for AP
After=wlan-ap.service
Requires=wlan-ap.service[Service]
ExecStartPre=/bin/sleep 3
ExecStart=/usr/sbin/hostapd /etc/hostapd/hostapd.conf
Restart=always[Install]
WantedBy=multi-user.target

hostapd 配置 /etc/hostapd/hostapd.conf

interface=wlp3s0_ap
driver=nl80211
ssid=MyHotspot
hw_mode=g
channel=6
wmm_enabled=1
auth_algs=1
ignore_broadcast_ssid=0
wpa=2
wpa_passphrase=12345678
wpa_key_mgmt=WPA-PSK
rsn_pairwise=CCMP

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4. dnsmasq DHCP 服务

1. 备份默认配置：

sudo mv /etc/dnsmasq.conf /etc/dnsmasq.conf.bak

2. 新建 /etc/dnsmasq.conf：

interface=wlp3s0_ap
bind-interfaces
dhcp-range=192.168.50.10,192.168.50.100,12h

3. 修改 dnsmasq systemd 依赖：

sudo systemctl edit dnsmasq

输入：

[Unit]
After=hostapd-ap.service
Requires=hostapd-ap.service[Service]
ExecStartPre=/bin/sleep 3

保存退出。

4. 启用并重载：

sudo systemctl daemon-reload
sudo systemctl enable dnsmasq

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5. 设置 NAT 转发

1. 启用 IP 转发：

sudo sysctl -w net.ipv4.ip_forward=1
echo "net.ipv4.ip_forward=1" | sudo tee -a /etc/sysctl.conf
sudo sysctl -p

2. 配置 iptables：

sudo iptables -t nat -A POSTROUTING -o wlp3s0 -j MASQUERADE
sudo iptables -A FORWARD -i wlp3s0_ap -o wlp3s0 -j ACCEPT
sudo iptables -A FORWARD -i wlp3s0 -o wlp3s0_ap -m state --state RELATED,ESTABLISHED -j ACCEPT

3. 保存规则：

sudo apt install iptables-persistent
sudo netfilter-persistent save

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6. STA 自动连接 Wi-Fi

nmcli dev wifi connect "YourWiFiSSID" password "YourWiFiPassword" ifname wlp3s0
nmcli connection modify "YourWiFiSSID" connection.autoconnect yes

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7. NetworkManager 忽略虚拟 AP 接口

编辑 /etc/NetworkManager/NetworkManager.conf：

[keyfile]
unmanaged-devices=interface-name:wlp3s0_ap

重启 NetworkManager：

sudo systemctl restart NetworkManager

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8. 开机启动顺序

1. unblock-wifi.service → 解锁 WLAN

2. wlan-ap.service → 创建虚拟接口 + 分配静态 IP

3. hostapd-ap.service → 启动 AP

4. dnsmasq.service → DHCP

5. NAT 转发 → 设备可上网

6. STA 自动连 Wi-Fi

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