From owner-freebsd-questions@freebsd.org Fri Jul 20 12:15:43 2018 Return-Path: Delivered-To: freebsd-questions@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id D877210434F0 for ; Fri, 20 Jul 2018 12:15:43 +0000 (UTC) (envelope-from matthew@FreeBSD.org) Received: from smtp.infracaninophile.co.uk (smtp.infracaninophile.co.uk [81.2.117.100]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "smtp.infracaninophile.co.uk", Issuer "infracaninophile.co.uk" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 6D5A67A0C2 for ; Fri, 20 Jul 2018 12:15:43 +0000 (UTC) (envelope-from matthew@FreeBSD.org) Received: from leaf.local (unknown [88.202.132.43]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: m.seaman@infracaninophile.co.uk) by smtp.infracaninophile.co.uk (Postfix) with ESMTPSA id 173D3CC15 for ; Fri, 20 Jul 2018 12:15:35 +0000 (UTC) Authentication-Results: smtp.infracaninophile.co.uk; dmarc=none (p=none dis=none) header.from=FreeBSD.org Authentication-Results: smtp.infracaninophile.co.uk/173D3CC15; dkim=none; dkim-atps=neutral Subject: Re: FreeBSD-11.1 Jails and SSL To: freebsd-questions@freebsd.org References: <56bbc3069975ec09b4771e57d138de64.squirrel@webmail.harte-lyne.ca> <39F372AB-BCCB-4A38-A351-F0F3ECCDEA21@lists.vlassakakis.de> From: Matthew Seaman Message-ID: Date: Fri, 20 Jul 2018 13:15:34 +0100 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.13; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-GB Content-Transfer-Encoding: 7bit X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.27 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 20 Jul 2018 12:15:44 -0000 On 19/07/2018 21:52, James B. Byrne via freebsd-questions wrote: > On Thu, July 19, 2018 16:38, Philipp Vlassakakis wrote: >>> Am 19.07.2018 um 22:29 schrieb James B. Byrne >>> : >>> >>> UseDNS=YES in /etc/ssh/sshd_config >> Does the problem persists, if you disable this option? >> > No, it does not persist. Log ons are now as fast as with any other > host. Why is UseDNS=YES (the default setting) a problem inside a jail > and nowhere else? > SSH is doing a reverse lookup on the IP number your connection comes from. It's possible you're timing out on the IP lookup specifically. Particularly if you're using private address space -- local_unbound has some special settings around the handling of RFC1918 zones -- so compare the per-jail config with you main host (which I presume has no similar problems?) Another potential gotcha is if your reverse IP space has a broken DNSSEC configuration: local_unbound defaults to enabling DNSSEC processing (indeed, that's the primary reason for having local_unbound at all) and DNSSEC signing failures will essentially make the affected data disappear from the DNS. Cheers, Matthew