From owner-freebsd-hackers Sun May 5 16:34:39 2002 Delivered-To: freebsd-hackers@freebsd.org Received: from utility.clubscholarship.com (utility.clubscholarship.com [198.78.70.175]) by hub.freebsd.org (Postfix) with ESMTP id 4734637B406 for ; Sun, 5 May 2002 16:34:32 -0700 (PDT) Received: from localhost (root@localhost) by utility.clubscholarship.com (8.11.6/8.11.6) with ESMTP id g45NVa479180 for ; Sun, 5 May 2002 16:31:36 -0700 (PDT) (envelope-from root@utility.clubscholarship.com) Date: Sun, 5 May 2002 16:31:36 -0700 (PDT) From: Patrick Thomas To: Subject: what causes a userland to stop, but allows kernel to continue ? Message-ID: <20020505162455.K86733-100000@utility.clubscholarship.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG So, based on a previous thread, it looks like I have a server whose userland halted, essentially, but the kernel continued running. As evidenced by: - you can still ping the server just fine - you can still connect to running services just fine - if you ssh to it, `ssh -v` (verbose) claims a connection is established, but the server doesn't respond in any way over that connection. Further, you can telnet to POP or IMAP or HTTP ports, and get a connection, but you can't get any response. - cron does NOT run while the server is in this state - no jobs run - no response from the console - caps lock does NOT toggle the LED So, as was suggested in the previous thread, it looks like my kernel is still running, but the userland has halted. There are no log entries that give any clue as to why this happened last week. 1. from a theoretical standpoint, how would this happen ? 2. Is there any way to watchdog for it and escape from it before the userland completely crashes ? 3. any previous/old problems that would cause this behavior ? It is a FreeBSD 4.5-RELEASE system, and it is SMP - fairly heavily loaded (averages 60% CPU idle in `top` output). thanks, PT To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message