Date: Mon, 4 Mar 2019 11:43:20 +0100 From: "Patrick M. Hausen" <hausen@punkt.de> To: FreeBSD Net <freebsd-net@freebsd.org> Subject: TCP-forwarding with netcat - weird failures ... Message-ID: <D3EF7ABA-7674-4F7B-8ED2-21CED3BFB975@punkt.de>
next in thread | raw e-mail | index | archive | help
Hi all, in a particular customer network we have a world wide VPN with partially overlapping addresses, renumbering impossible due to political reasons, and all the fun you can have in the „enterprise“ environment. No IPv6 either, newfangled nonsense … :-/ So to access a certain set of services we installed a VMware virtual machine running FreeBSD at the VPN’s central hub and users in subsidiary offices use the IP address and certain ports on this machine which then hands off to the target service that is not reachable from the subsidiary. Setup is dead simple, just one example: /etc/services: oediv-3243 3243/tcp /etc/inetd.conf: oediv-3243 stream tcp nowait nobody /usr/bin/nc nc 172.20.1.166 3243 The machine has been in service for 10+ years and runs FreeBSD 6.4. So what’s the problem? The VMware environment that hosts this machine is about to be retired. So I installed a fresh VM with FreeBSD 11.2 plus current VMware-tools and copied the setup. Then we shutdown the old machine and booted the new one with identical IP address. Needless to say: doesn’t work. And no, it’s not the obvious ARP caches. Connections can be established but then abort spontaneously without an observable pattern or reason. We already found that more modern netcat/nc needs „-N“ to close the connections on EOF, but besides … Does anyone know what might have changed that could cause connection problems? Kind regards, Patrick -- punkt.de GmbH Internet - Dienstleistungen - Beratung Kaiserallee 13a Tel.: 0721 9109-0 Fax: -100 76133 Karlsruhe info@punkt.de http://punkt.de AG Mannheim 108285 Gf: Juergen Egeling
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?D3EF7ABA-7674-4F7B-8ED2-21CED3BFB975>