From owner-freebsd-questions@freebsd.org Fri Jul 26 16:12:06 2019 Return-Path: Delivered-To: freebsd-questions@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id 5BC18A425D for ; Fri, 26 Jul 2019 16:12:06 +0000 (UTC) (envelope-from dpchrist@holgerdanske.com) Received: from holgerdanske.com (holgerdanske.com [184.105.128.27]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "holgerdanske.com", Issuer "holgerdanske.com" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id A993D6FD10 for ; Fri, 26 Jul 2019 16:12:05 +0000 (UTC) (envelope-from dpchrist@holgerdanske.com) Received: from 99.100.19.101 ([99.100.19.101]) by holgerdanske.com with ESMTPSA (ECDHE-RSA-AES128-GCM-SHA256:TLSv1.2:Kx=ECDH:Au=RSA:Enc=AESGCM(128):Mac=AEAD) (SMTP-AUTH username dpchrist@holgerdanske.com, mechanism PLAIN) for ; Fri, 26 Jul 2019 09:11:56 -0700 Subject: Re: Help:: Listen queue overflow killing servers To: freebsd-questions@freebsd.org References: <3a62375a-432c-3533-a7bc-e5573c26fa9c@ifdnrg.com> From: David Christensen Message-ID: <2b10f991-bc95-ae31-18e2-95ae943ac527@holgerdanske.com> Date: Fri, 26 Jul 2019 09:11:56 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: <3a62375a-432c-3533-a7bc-e5573c26fa9c@ifdnrg.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit X-Rspamd-Queue-Id: A993D6FD10 X-Spamd-Bar: - Authentication-Results: mx1.freebsd.org X-Spamd-Result: default: False [-1.99 / 15.00]; ARC_NA(0.00)[]; RCVD_VIA_SMTP_AUTH(0.00)[]; NEURAL_HAM_MEDIUM(-0.99)[-0.990,0]; FROM_HAS_DN(0.00)[]; TO_MATCH_ENVRCPT_ALL(0.00)[]; IP_SCORE(-0.40)[ipnet: 184.104.0.0/15(0.85), asn: 6939(-2.80), country: US(-0.05)]; MIME_GOOD(-0.10)[text/plain]; PREVIOUSLY_DELIVERED(0.00)[freebsd-questions@freebsd.org]; TO_DN_NONE(0.00)[]; AUTH_NA(1.00)[]; RCPT_COUNT_ONE(0.00)[1]; NEURAL_HAM_LONG(-1.00)[-0.996,0]; DMARC_NA(0.00)[holgerdanske.com]; MX_GOOD(-0.01)[holgerdanske.com]; NEURAL_HAM_SHORT(-0.49)[-0.494,0]; RCVD_IN_DNSWL_NONE(0.00)[27.128.105.184.list.dnswl.org : 127.0.10.0]; R_SPF_NA(0.00)[]; FROM_EQ_ENVFROM(0.00)[]; R_DKIM_NA(0.00)[]; MIME_TRACE(0.00)[0:+]; ASN(0.00)[asn:6939, ipnet:184.104.0.0/15, country:US]; MID_RHS_MATCH_FROM(0.00)[]; RCVD_TLS_ALL(0.00)[]; RCVD_COUNT_TWO(0.00)[2] X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 26 Jul 2019 16:12:06 -0000 On 7/26/19 4:58 AM, Paul Macdonald via freebsd-questions wrote: > Over the past few months i've seen several boxes (4 or 5) become > unresponsive as a result of a Listen queue overflow state. > All are on ZFS and are std apache/php/mysql servers with nothing too > exotic. > /var/log/messages shows tyically; > >     kernel: sonewconn: pcb 0xfffff813395e3d58: Listen queue overflow: > 193 already in queue awaiting acceptance (83 occurrences) > > netstat -Lan  shows > > tcp4 193/0/128                          x.x.x.x.443 > tcp4  193/0/128                          x.x.x.x.80 What Apache/ PHP/ MySQL applications? Did you write them? If not, who did? Is everything up to date? Have you filed bug reports? Do the applications have logging or debugging capabilities? Have you enabled them? What do they say? Where is the blockage? Deadlock? David