From mboxrd@z Thu Jan 1 00:00:00 1970 From: Simon Kelley Subject: Re: ipv6 and ipv4 interaction weirdness Date: Fri, 11 Mar 2005 14:21:02 +0000 Message-ID: <4231A94E.9020904@thekelleys.org.uk> References: <20050311121655.GE14146@zip.com.au> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Cc: linux-kernel@vger.kernel.org, netdev@oss.sgi.com, pekkas@netcore.fi, yoshfuji@linux-ipv6.org To: CaT In-Reply-To: <20050311121655.GE14146@zip.com.au> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org CaT wrote: > I just had some issues with ssh and trying to get it to bind to all ipv6 > and ipv4 addresses to it via :: and 0.0.0.0. The problem was that it'd > only let one succeed. If 0.0.0.0:22 was successful then :: port 22 could > not happen and neither could my ipv6 addy port 22 as it would get the > 'address already in use' error from bind(). The reverse was also true. > If it bound to :: port 22 then 0.0.0.0:22 would fail. > > On the other hand if I got it to bind to each address individually then > both ipv4 (2 addresses) and ipv6 (1 address) binds would succeed. > > Maybe I'm just looking at it wrong but shouldn't ipv4 and ipv6 interfere > with each other? > > I'm using kernel 2.6.11-ac2 with OpenSSH_3.8.1p1 Debian-8.sarge.4, > OpenSSL 0.9.7e 25 Oct 2004 and glibc 2.3.2 (debian version > 2.3.2.ds1-20). > A solution is to set the IPV6_V6ONLY sockopt on the IPv6 socket (or just use IPv6 sockets and their ability to accept IPv4 connections in a corner of the IPv6 address space). It seems unlikely that a released ssh would have that problem, but I haven't checked. Cheers, Simon.