From patchwork Fri Aug 30 16:27:24 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Scott Mayhew X-Patchwork-Id: 11124331 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 3310618B7 for ; Fri, 30 Aug 2019 16:27:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1A6482186A for ; Fri, 30 Aug 2019 16:27:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728186AbfH3Q1Z (ORCPT ); Fri, 30 Aug 2019 12:27:25 -0400 Received: from mx1.redhat.com ([209.132.183.28]:49242 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728169AbfH3Q1Z (ORCPT ); Fri, 30 Aug 2019 12:27:25 -0400 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 2BF0B1893FB1 for ; Fri, 30 Aug 2019 16:27:25 +0000 (UTC) Received: from coeurl.usersys.redhat.com (ovpn-121-35.rdu2.redhat.com [10.10.121.35]) by smtp.corp.redhat.com (Postfix) with ESMTP id 12B12600F8; Fri, 30 Aug 2019 16:27:25 +0000 (UTC) Received: by coeurl.usersys.redhat.com (Postfix, from userid 1000) id B8A1520B4C; Fri, 30 Aug 2019 12:27:24 -0400 (EDT) From: Scott Mayhew To: steved@redhat.com Cc: linux-nfs@vger.kernel.org Subject: [nfs-utils PATCH v2 4/4] nfsdcld: update nfsdcld.man Date: Fri, 30 Aug 2019 12:27:24 -0400 Message-Id: <20190830162724.13862-5-smayhew@redhat.com> In-Reply-To: <20190830162724.13862-1-smayhew@redhat.com> References: <20190830162724.13862-1-smayhew@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.6.2 (mx1.redhat.com [10.5.110.70]); Fri, 30 Aug 2019 16:27:25 +0000 (UTC) Sender: linux-nfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org Added some historical information to the notes section, along with some information regarding upgrading and downgrading nfsdcld. Signed-off-by: Scott Mayhew --- utils/nfsdcld/nfsdcld.man | 32 +++++++++++++++++++++++++++----- 1 file changed, 27 insertions(+), 5 deletions(-) diff --git a/utils/nfsdcld/nfsdcld.man b/utils/nfsdcld/nfsdcld.man index c271d14..4c2b1e8 100644 --- a/utils/nfsdcld/nfsdcld.man +++ b/utils/nfsdcld/nfsdcld.man @@ -185,15 +185,37 @@ on stable storage by manipulating information on the filesystem directly, in the directory to which \fI/proc/fs/nfsd/nfsv4recoverydir\fR points. .PP -This daemon requires a kernel that supports the nfsdcld upcall. If the -kernel does not support the new upcall, or is using the legacy client -name tracking code then it will not create the pipe that nfsdcld uses to -talk to the kernel. +This changed with the original introduction of \fBnfsdcld\fR upcall in kernel version 3.4, +which was later deprecated in favor of the \fBnfsdcltrack\fR(8) usermodehelper +program, support for which was added in kernel version 3.8. However, since the +usermodehelper upcall does not work in containers, support for a new version of +the \fBnfsdcld\fR upcall was added in kernel version 5.2. +.PP +This daemon requires a kernel that supports the \fBnfsdcld\fR upcall. On older kernels, if +the legacy client name tracking code was in use, then the kernel would not create the +pipe that \fBnfsdcld\fR uses to talk to the kernel. On newer kernels, nfsd attempts to +initialize client tracking in the following order: First, the \fBnfsdcld\fR upcall. Second, +the \fBnfsdcltrack\fR usermodehelper upcall. Finally, the legacy client tracking. .PP This daemon should be run as root, as the pipe that it uses to communicate with the kernel is only accessable by root. The daemon however does drop all superuser capabilities after starting. Because of this, the \fIstoragedir\fR should be owned by root, and be readable and writable by owner. +.PP +The daemon now supports different upcall versions to allow the kernel to pass additional +data to be stored in the on-disk database. The kernel will query the supported upcall +version from \fBnfsdcld\fR during client tracking initialization. A restart of \fBnfsd\fR is +not necessary after upgrading \fBnfsdcld\fR, however \fBnfsd\fR will not use a later upcall +version until restart. A restart of \fBnfsd is necessary\fR after downgrading \fBnfsdcld\fR, +to ensure that \fBnfsd\fR does not use an upcall version that \fBnfsdcld\fR does not support. +Additionally, a downgrade of \fBnfsdcld\fR requires the schema of the on-disk database to +be downgraded as well. That can be accomplished using the \fBclddb-tool\fR(8) utility. +.SH FILES +.TP +.B /var/lib/nfs/nfsdcld/main.sqlite +.SH SEE ALSO +.BR nfsdcltrack "(8), " clddb-tool (8) .SH "AUTHORS" .IX Header "AUTHORS" -The nfsdcld daemon was developed by Jeff Layton . +The nfsdcld daemon was developed by Jeff Layton +with modifications from Scott Mayhew .