Return-Path: linux-nfs-owner@vger.kernel.org Received: from mx1.redhat.com ([209.132.183.28]:55417 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753232AbaKLPBy (ORCPT ); Wed, 12 Nov 2014 10:01:54 -0500 Date: Wed, 12 Nov 2014 10:01:48 -0500 (EST) From: Benjamin Coddington To: Trond Myklebust cc: Linux NFS Mailing List Subject: Re: mount default minor version behavior In-Reply-To: Message-ID: References: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-nfs-owner@vger.kernel.org List-ID: On Wed, 12 Nov 2014, Trond Myklebust wrote: > On Wed, Nov 12, 2014 at 8:09 AM, Benjamin Coddington > wrote: > > Here's a quick summary of where the threads ended up: > > > > - Everyone agrees that if a specific minor version is specified, only > > that version should be attempted. > > > > - On the issue of minor version omission, the positions are: > > 1) vers=4 means try 4.1, 4.0. > > Steve D > > Boaz > > Ben C > > So where does the number 4.1 come from here? Is that a compile option? > That means we would need to recompile every time someone wants to bump > the version number to a new default. Right now it is - one reason is that the version parsing code is not very dynamic; I'll change that. Another reason is that mount.nfs returns an error for invalid values of vers= instead of attempting them. I should just change that as well since it doesn't match the behavior of the the v# option which is always passed on to the kernel. So mount.nfs will be version-impartial. That resolves the case where the minor version is not specified and the config file is not used/set: we must chose 0 for a minor version since mount.nfs will have no other way to determine which minor version should be used. That's what I'll do unless there's any other objections. Thanks for weighing in, everyone. Ben > > 2) vers=4 means try 4.0 only. > > Andros > > Anna > > Frank > > > > 3) vers=4 means > > - if conf file defaultvers=4.1, try 4.1, 4.0. > > - else if defaultvers not set try 4.0 only. > > Trond > > > > Anyone else want to weigh in? Trond's position can also count towards > > the second position because we should consider the case where the config > > file is not used or turned off in the build. I think I could just add a > > bit to the config file that switches between 1 and 2, something like > > "usebestversion", which defaults to position 2. That would allow a > > distro to use the first behavior if they chose. > > > > Ben > > > > > > On Tue, 11 Nov 2014, Benjamin Coddington wrote: > > > >> I will update mount.nfs so the default version is 4.1. I have two quick > >> questions on desired behavior: > >> > >> o Should mounts that do not specify a minor version be upgraded to the > >> default minor version? > >> > >> For example, should 'mount -overs=4' turn into 'mount -overs4.1', if the > >> current default is 4.1? > >> > >> > >> o If 'yes' to the above, should mount auto-retry decrementing minor > >> versions if EPROTONOSUPPORT? > >> > >> For example, 'mount -overs=4' with a default of 4.2 would attempt: 4.2, > >> then 4.1, then 4.0. > >> > >> Ben > >> -- > >> To unsubscribe from this list: send the line "unsubscribe linux-nfs" in > >> the body of a message to majordomo@vger.kernel.org > >> More majordomo info at http://vger.kernel.org/majordomo-info.html > >> > > -- > > To unsubscribe from this list: send the line "unsubscribe linux-nfs" in > > the body of a message to majordomo@vger.kernel.org > > More majordomo info at http://vger.kernel.org/majordomo-info.html > > > > -- > Trond Myklebust > > Linux NFS client maintainer, PrimaryData > > trond.myklebust@primarydata.com >