From owner-freebsd-questions@freebsd.org Thu Feb 9 23:48:01 2017 Return-Path: Delivered-To: freebsd-questions@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 97F3ACD8795 for ; Thu, 9 Feb 2017 23:48:01 +0000 (UTC) (envelope-from freebsd@edvax.de) Received: from mailrelay10.qsc.de (mailrelay10.qsc.de [212.99.163.152]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "*.antispameurope.com", Issuer "TeleSec ServerPass DE-2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 0DD641C0C for ; Thu, 9 Feb 2017 23:48:00 +0000 (UTC) (envelope-from freebsd@edvax.de) Received: from mx01.qsc.de ([213.148.129.14]) by mailrelay10.qsc.de; Fri, 10 Feb 2017 00:47:06 +0100 Received: from r56.edvax.de (port-92-195-22-222.dynamic.qsc.de [92.195.22.222]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mx01.qsc.de (Postfix) with ESMTPS id DE2783CBF9; Fri, 10 Feb 2017 00:46:59 +0100 (CET) Received: from r56.edvax.de (localhost [127.0.0.1]) by r56.edvax.de (8.14.5/8.14.5) with SMTP id v19Nkw4q002060; Fri, 10 Feb 2017 00:46:59 +0100 (CET) (envelope-from freebsd@edvax.de) Date: Fri, 10 Feb 2017 00:46:58 +0100 From: Polytropon To: The Doctor Cc: freebsd-questions@freebsd.org Subject: Re: Hung server Message-Id: <20170210004658.8d24fd54.freebsd@edvax.de> In-Reply-To: <20170209232150.GA11245@doctor.nl2k.ab.ca> References: <20170209232150.GA11245@doctor.nl2k.ab.ca> Reply-To: Polytropon Organization: EDVAX X-Mailer: Sylpheed 3.1.1 (GTK+ 2.24.5; i386-portbld-freebsd8.2) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-cloud-security-sender: freebsd@edvax.de X-cloud-security-recipient: freebsd-questions@freebsd.org X-cloud-security-Virusscan: CLEAN X-cloud-security-disclaimer: This E-Mail was scanned by E-Mailservice on mailrelay10.qsc.de with 45139683645 X-cloud-security-connect: mx01.qsc.de[213.148.129.14], TLS=1, IP=213.148.129.14 X-cloud-security: scantime:.1794 X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 09 Feb 2017 23:48:01 -0000 On Thu, 9 Feb 2017 16:21:50 -0700, The Doctor wrote: > Question? I s there a way of detecting why a server > hangs? Can you be more specific? > Within the last month my Primary Server > has been going into infinity mood as like to > call it for about 2 hours at a time. > > No signal can get through. So you're observing the "networking aspect" of that server? Do you have a non-network connection (direct console, serial line, IPMI or something like that) that you can examine? > Is this a kernel or app issue? Could be even more, for example a firewall issue. A system completely hanging often indicates a lower level problem, for example related to the kernel or a device driver, but without proper diagnostics, it's really hard to tell. As I said, if everything you can observe happens on the "network aspect", it could as well be a firewall (of the server, or _infront of_ the server) that just blocks traffic while the programs the server runs keep working as intended... -- Polytropon Magdeburg, Germany Happy FreeBSD user since 4.0 Andra moi ennepe, Mousa, ...