From owner-freebsd-hackers@FreeBSD.ORG Fri May 19 14:04:20 2006 Return-Path: X-Original-To: freebsd-hackers@freebsd.org Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id B5C5516A422 for ; Fri, 19 May 2006 14:04:20 +0000 (UTC) (envelope-from cel@citi.umich.edu) Received: from citi.umich.edu (citi.umich.edu [141.211.133.111]) by mx1.FreeBSD.org (Postfix) with ESMTP id 5CB7E43D53 for ; Fri, 19 May 2006 14:04:20 +0000 (GMT) (envelope-from cel@citi.umich.edu) Received: from [192.168.0.100] (nat-198-95-226-230.netapp.com [198.95.226.230]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "Chuck Lever", Issuer "CITI Production KCA" (verified OK)) by citi.umich.edu (Postfix) with ESMTP id 4C3541BBAB; Fri, 19 May 2006 10:04:19 -0400 (EDT) Message-ID: <446DD05F.6070304@citi.umich.edu> Date: Fri, 19 May 2006 10:04:15 -0400 From: Chuck Lever Organization: Center for Information Technology Integration User-Agent: Thunderbird 1.5.0.2 (Macintosh/20060308) MIME-Version: 1.0 To: babkin@users.sf.net References: <18923565.8854391148037026048.JavaMail.root@vms168.mailsrvcs.net> In-Reply-To: <18923565.8854391148037026048.JavaMail.root@vms168.mailsrvcs.net> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: freebsd-hackers@freebsd.org, Steven Hartland Subject: Re: NFS server not responding prevents boot X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: cel@citi.umich.edu List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 19 May 2006 14:04:21 -0000 Sergey Babkin wrote: >> From: Steven Hartland > >>> Anyway the big question is how can I change all our NFS >>> mounts so that failed mounts dont prevent the machines >>> booting to the point where they can be fixed remotely >>> i.e. have started sshd. >> Doh!! spent ages googling for the answer then found it >> in 2mins of looking through the man pages. >> >> The option for anyone interested is "bg" for -b from >> the command line to mount: >> [quote="man mount_nfs"] >> -b >> If an initial attempt to contact the server fails, fork off a > > I usually use "soft,bg". The "soft" option makes the > operations on this filesystem fail if the server > is not available instead of hanging (unkillable!) > forever and waiting for the server to come up. "soft" is usually a bad idea if you care about data integrity. It can cause all kinds of silent data corruption. Even on read-only mounts, a soft timeout can cause clients to corrupt their own caches. If you absolutely must use "soft", then also use NFS over TCP, and use a long retransmit timeout (like 60 seconds) and enable the dumb timer (the "-d") option. That's about the safest way to use "soft". -- corporate: cel at netapp dot com personal: chucklever at bigfoot dot com