回複：路由器(192.168.1.x)後麵接一個SPA2102網絡電話適配器，適配器(192.168.7.x)接一台電腦上網。

Okay, your best option would be using your spa2102's routing part as your router. then, disable the routing part of your router and connect your pc. this way, all your network devices are on the same subnet. the way you were talking about create more problems since you have two dhcp providing two sets of local ip addresses.
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