From owner-freebsd-xen@FreeBSD.ORG Mon Mar 17 17:18:24 2014 Return-Path: Delivered-To: freebsd-xen@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 2D7A4DFF for ; Mon, 17 Mar 2014 17:18:24 +0000 (UTC) Received: from SMTP.CITRIX.COM (smtp.citrix.com [66.165.176.89]) (using TLSv1 with cipher RC4-SHA (128/128 bits)) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id 65D05ECB for ; Mon, 17 Mar 2014 17:18:22 +0000 (UTC) X-IronPort-AV: E=Sophos;i="4.97,671,1389744000"; d="scan'208";a="112190630" Received: from accessns.citrite.net (HELO FTLPEX01CL03.citrite.net) ([10.9.154.239]) by FTLPIPO01.CITRIX.COM with ESMTP; 17 Mar 2014 17:17:55 +0000 Received: from [IPv6:::1] (10.80.16.47) by smtprelay.citrix.com (10.13.107.80) with Microsoft SMTP Server id 14.2.342.4; Mon, 17 Mar 2014 13:17:54 -0400 Message-ID: <53272E41.3050409@citrix.com> Date: Mon, 17 Mar 2014 18:17:53 +0100 From: =?ISO-8859-1?Q?Roger_Pau_Monn=E9?= User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.7; rv:24.0) Gecko/20100101 Thunderbird/24.3.0 MIME-Version: 1.0 To: Karl Pielorz , Subject: Re: FBSD 10.0-S (r261289M) under XenServer 6.2 - Stuck sshd in urdlck? References: <4B8380EBE379080FAD3271FA@Mail-PC.tdx.co.uk> In-Reply-To: <4B8380EBE379080FAD3271FA@Mail-PC.tdx.co.uk> X-Enigmail-Version: 1.6 Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit X-DLP: MIA2 X-BeenThere: freebsd-xen@freebsd.org X-Mailman-Version: 2.1.17 Precedence: list List-Id: Discussion of the freebsd port to xen - implementation and usage List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 17 Mar 2014 17:18:24 -0000 On 17/03/14 17:59, Karl Pielorz wrote: > > Hi, > > I setup a VM a while ago under XenServer 6.2 - it's an amd64 FBSD 10.0-S > box (based on r261289) - it's running under Xen PVHVM. > > I set it up - and left it for a while (46 days). I went to ssh to it > today, and got: > > " > ssh_exchange_identification: Connection closed by remote host > " > > Getting on to the boxes console there's lots of what look to be 'stuck' > sshd processes? > > 0 3933 895 0 20 0 84868 6944 urdlck Is - 0:00.01 sshd: unknown > [priv] (sshd) > 22 3934 3933 0 20 0 0 0 - Z - 0:00.00 > 0 3935 3933 0 20 0 84868 6952 sbwait I - 0:00.00 sshd: unknown > [pam] (sshd) > 0 4338 895 0 20 0 84868 6944 urdlck Is - 0:00.01 sshd: unknown > [priv] (sshd) > 22 4339 4338 0 20 0 0 0 - Z - 0:00.00 > > > Anyone know what 'urdlck' is? It seems like the process is stuck while trying to acquire a rw mutex in read mode. Could you obtain a backtrace of the process with gdb? Also a kernel-space dump might be useful, could you also run procstat -k ? > > There's 126 of these processes, e.g. > > 5446 - I 0:00.00 sshd: unknown [pam] (sshd) > 5450 - Is 0:00.01 sshd: unknown [priv] (sshd) > 5452 - I 0:00.00 sshd: unknown [pam] (sshd) > 5453 - Is 0:00.01 sshd: unknown [priv] (sshd) > > > Bearing in mind the box is firewalled from ssh access, and no one (apart > from me today) has attempted to get onto the box with ssh - this is a > little concerning. Every about 5-10 connects will actually 'connect' - > the rest just result in the 'key exchange' error. > > Kernel is GENERIC with: > > options NO_ADAPTIVE_MUTEXES > options NO_ADAPTIVE_RWLOCKS > options NO_ADAPTIVE_SX > > There's nothing logged in dmesg, or syslog. > > Is there anything worth doing to this VM before I restart it - i.e. to > try and figure out what's happened? / troubleshoot? > > -Karl > > _______________________________________________ > freebsd-xen@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-xen > To unsubscribe, send any mail to "freebsd-xen-unsubscribe@freebsd.org"