Return-Path: Received: from mail-qk0-f176.google.com ([209.85.220.176]:36145 "EHLO mail-qk0-f176.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751383AbbFGJIW (ORCPT ); Sun, 7 Jun 2015 05:08:22 -0400 Received: by qkx62 with SMTP id 62so63439106qkx.3 for ; Sun, 07 Jun 2015 02:08:21 -0700 (PDT) Message-ID: <55740A02.3010700@gmail.com> Date: Sun, 07 Jun 2015 17:08:18 +0800 From: Kinglong Mee MIME-Version: 1.0 To: Sean Elble , linux-nfs@vger.kernel.org, Steve Dickson Subject: Re: rpc.nfsd Host Option & IPv6 References: <5574099C.9090205@gmail.com> In-Reply-To: <5574099C.9090205@gmail.com> Content-Type: text/plain; charset=utf-8 Sender: linux-nfs-owner@vger.kernel.org List-ID: On 6/7/2015 5:06 PM, Kinglong Mee wrote: > Cc steve, > > On 6/3/2015 9:39 PM, Sean Elble wrote: >> Hi all, >> >> While it seems that most folks use iptables to restrict access to single interfaces when multihomed hosts are acting as NFS servers, I do see that there is a "--host" option that can be provided to rpc.nfsd when it starts so that it only binds to a specific IP/interface. >> >> This does seem to work nicely, but when I try to use it, it throws an error/warning (where nfs-server is defined in /etc/hosts for the IPv4 address of the interface I wish for TCP port 2049 to be opened on): >> >> rpc.nfsd: unable to resolve nfs-server:nfs to inet6 address: Name or service not known > > It is caused by that rpc.nfsd try to bind IPv4 and IPv6 address default. > you don't support an IPv6 address, so rpc.nfsd print the message. > > But, IPv4 is work correctly. > >> >> Commenting out the following lines in /etc/netconfig (as suggested by the Google) allows the daemon to start without error: >> >> udp6 tpi_clts v inet6 udp - - >> tcp6 tpi_cots_ord v inet6 tcp - - > > If you comment those lines, rpc.nfsd will check /etc/netconfig and find udp6/tcp6 is not allowed, Sorry, udp6/tcp6 should be inet6 here. thanks, Kinglong Mee > so, rpc.nfsd will not bind IPv6 address, the message is not printed. > >> >> But I'm wondering if that is the only means for this to work, particularly considering that I'd expect changes to /etc/netconfig to apply to more than just rpc.nfsd. > > Agree with you. > >> >> It is worth noting that 1) this seems to apply equally to Debian-based and RHEL-based systems and 2) things seem to work even with the error, but I wouldn't have expected to see that message for something (seemingly) so simple. > > I think we should not print the message as you want. > > thanks, > Kinglong Mee >