Return-Path: trond.myklebust@primarydata.com MIME-Version: 1.0 In-Reply-To: <5463787A.7080404@RedHat.com> References: <5462608B.1090607@RedHat.com> <54635BB5.1020702@RedHat.com> <5463787A.7080404@RedHat.com> Date: Wed, 12 Nov 2014 10:28:53 -0500 Message-ID: Subject: Re: mount default minor version behavior From: Trond Myklebust To: Steve Dickson Cc: Benjamin Coddington , Linux NFS Mailing List Content-Type: text/plain; charset=UTF-8 List-ID: On Wed, Nov 12, 2014 at 10:10 AM, Steve Dickson wrote: > > > On 11/12/2014 09:31 AM, Trond Myklebust wrote: >>> My point is I don't think we need another variable, say >>> > DefaultMinVers, that defines the minor version of v4. I'm >>> > thinking that's its overkill and adds unnecessary complexity. >>> > >> I never said we do. > Ok... I misunderstood... > >> >> I think we're in agreement mostly; the only point where I see >> disagreement is when Defaultvers is unset. >> My position is that in that situation, we don't know what starting >> point to use for minor version negotiation, and so we should just >> default to minor version 0: if the sysadmin want a different default, >> then the answer is to set Defaultvers... > Gotta... and there is a disagreement... I saying we make the > default the highest supported minor version. With the > Linux client and server that's v4.2. So when no option is > given and Defaultvers is not set, try 4.2, then 4.1 and > then 4.0 and finally v3. Only for Linux 3.11 and newer, and only if they enable CONFIG_NFS_V4_2 / CONFIG_NFSD_V4_SECURITY_LABEL. Unless we want to have different defaults for older kernels, this sort of implies that we're moving in the direction of coupling the nfs-utils releases more tightly to the kernel version. I'm neutral to that, but I do want to call it out. > But I do see your point of not having to recompile mount > when we want to change the default minor release so > how that default is set is the question... Maybe > an environment variable?? That's still something that requires a user or sysadmin action, and it wouldn't really play well with autofs and its ilk. As Marie Antoinette would say: "Let them edit /etc/nfsmount.conf" > One down side of being the aggressive with minor version > negotiation is legacy servers (aka AIX). Today we > don't negotiate well with those types of servers... > Its not our fault, but is a problem... Is this because they don't implement that part of RFC3530? -- Trond Myklebust Linux NFS client maintainer, PrimaryData trond.myklebust@primarydata.com