From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: stefan@agner.ch Received: from krantz.zx2c4.com (localhost [127.0.0.1]) by krantz.zx2c4.com (ZX2C4 Mail Server) with ESMTP id dd8b918e for ; Wed, 4 Jul 2018 21:05:18 +0000 (UTC) Received: from mail.kmu-office.ch (mail.kmu-office.ch [IPv6:2a02:418:6a02::a2]) by krantz.zx2c4.com (ZX2C4 Mail Server) with ESMTP id 4f76fcd4 for ; Wed, 4 Jul 2018 21:05:18 +0000 (UTC) Received: from webmail.kmu-office.ch (unknown [IPv6:2a02:418:6a02::a3]) by mail.kmu-office.ch (Postfix) with ESMTPSA id B0FAD5C015F for ; Wed, 4 Jul 2018 23:11:52 +0200 (CEST) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Date: Wed, 04 Jul 2018 23:11:50 +0200 From: Stefan Agner To: wireguard@lists.zx2c4.com Subject: Android: TCP connection drop when disabling WiFi Message-ID: List-Id: Development discussion of WireGuard List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Hi, I am using WireGuard for Android v0.0.20180625 with the Go userspace backend. I am using a WiFi router with OpenWrt as Wireguard endpoint (WAN/internet address). Wireguard tunnels all traffic through the tunnel (Allowed IPs 0.0.0.0/0, ::/0). This works as expected: I can connect to the Internet through the tunnel no matter whether I am locally on the WiFi or connecting through 4G. Wireguard reconnects seamlessly. Now what I hope is that my TCP connection stay alive when roaming from WiFi to 4G. Since Wireguard reconnects automatically and my public IP through the tunnel stays the same, I would expect that I can have a SSH connection open while roaming from WiFi to 4G and back. I am using the SSH client ConnectBot to connect to an (IPv6) server. When changing from 4G to WiFi, the connection stays alive. However, when switching off WiFi (and hence change back to 4G) ConnectBot immediately reports "Host has disconnected.". It seems as if Android somehow drops all TCP connection when WiFi connection gets lost... Is this a known behavior? Anybody else observes the same behavior? It seems somewhat unfortunate as I would have hoped that Wireguard lets me keep sessions open... Also tried with a second SSH client, so it seems a common behavior. I am using a Nexus 6P with Stock Android 8.1.0. -- Stefan