From owner-freebsd-questions@FreeBSD.ORG Sat Nov 24 01:57:57 2012 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 9441EEE7 for ; Sat, 24 Nov 2012 01:57:57 +0000 (UTC) (envelope-from paul@kraus-haus.org) Received: from mail-la0-f54.google.com (mail-la0-f54.google.com [209.85.215.54]) by mx1.freebsd.org (Postfix) with ESMTP id 14BF48FC14 for ; Sat, 24 Nov 2012 01:57:56 +0000 (UTC) Received: by mail-la0-f54.google.com with SMTP id j13so9154511lah.13 for ; Fri, 23 Nov 2012 17:57:55 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type:x-gm-message-state; bh=ATz1ggbSzDWpxGV6RJDKInCNrDcsQh5W4rNy3USaU1w=; b=F7NqntS9OEFkv9TDvarl3xz5NfimmcwTWHRG11lntXhev165gmWWXvtFJjRwtQvAao cC9ntFQmGplq6F0TekDOzrkKAnUxXKkh4+B+0YgTLcVG7Xo1b7a+ROljMyVwts/ngw8i Ikn/HmTiiW4cGR+AareuE6Pmbr0S9145jNM6Py93coDlv54yQBKvUq9dakeghwYMJEpd LV/6g7hoU6cnVCN58JPWdbCifmOytFJY9B15Qc/3chPChs4EjhaZmahB2IvJug3MCfdn 8v0BxdIcOkFeNs24O00TufaRnJjbUMc/jRbmUwA3RK6N5EynZzK4L6erLCWdGhQ7h3Hc Cc3g== MIME-Version: 1.0 Received: by 10.112.47.42 with SMTP id a10mr2516599lbn.30.1353722275386; Fri, 23 Nov 2012 17:57:55 -0800 (PST) Received: by 10.114.27.138 with HTTP; Fri, 23 Nov 2012 17:57:55 -0800 (PST) In-Reply-To: <44obioatvk.fsf@lowell-desk.lan> References: <44obioatvk.fsf@lowell-desk.lan> Date: Fri, 23 Nov 2012 20:57:55 -0500 Message-ID: Subject: Re: Odd X11 over SSH issue From: Paul Kraus To: freebsd-questions@freebsd.org Content-Type: text/plain; charset=ISO-8859-1 X-Gm-Message-State: ALoCoQm7iNc50AJdR3f+f9UVLoOORhvszJnVgSukGk3cwcFAzj5vDVtwafNjlcgVdZ8o7rrXwjCo X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 24 Nov 2012 01:57:57 -0000 On Fri, Nov 23, 2012 at 4:31 PM, Lowell Gilbert wrote: >> Observations: >> >> 1. When I first SSH into the box I see a long delay after the SSH >> tunnel is setup before being prompted for a password, and I do not >> know if this delay is related to the VBox issue. Details below. > > Running the ssh server with more debugging will probably tell you what's > happening in this area. Yup, I just have not had a chance to chase that one down, and given that it happens once per SSH session, has not been a high priority. I mentioned it in the spirit of full disclosure. >> I would chock it up to network slowness, but I >> do not see the same behavior with Firefox, xload, or xclock. > > That's not a fair comparison, because tunneling a whole X server > involves passing a lot more events than tunneling an application to run > on your local server. This is particularly painful because the X > protocols are highly serial. The VIrtualBox GUI (not the underlying VM console) should be comparable to Firefox in terms of network load. Yes, xclock and xload are much lower overhead as they are simpler apps. The difference between Firefox (measured at under 10 seconds to open the window) and VirtualBox (measured at 157 seconds to open the window) indicates that _something_ is wrong. Sorry if I was unclear. I am running 3 different VMs on this server (soon to be more :-). One is WIn 2008 server as an RDP host for a specific application, the others ar FreeBSD VMs, one for DNS and DHCP, and the other for email / webmail. I manage the underlying Win 2008 instance via RDP (and that is how the end users connect), the two FreeBSD VMs do not run a window manager at all and they are managed via SSH connections. I use the VBoxHeadless executable to run the VMs for production use. Normally I make config changes with the command line tool VBoxManage, but in this case I had a FreeBSD VM that was not booting so I needed the console (and to make various changes to the config). It is running the VBox management GUI on the physical layer server that I am having fits with. > Is there any particular reason you don't let the X server run remotely > and attach to it with something more latency-friendly, like vnc? I would > expect that to work vastly better on any OS, just because you get X > (specifically, its tendency to head-of-line blocking) out of its own way. The short answer to why X11 via SSH and not VNC for the management is that I have not found a very clean way to have the VNC service running for root without manual intervention to start it. Yes, I know I could script it, but that adds one additional layer that needs to be supported. P.S. I did get my VM repaired, very slowly and painfully, but I still need to track down the VBox GUI issue. -- {--------1---------2---------3---------4---------5---------6---------7---------} Paul Kraus -> Principal Consultant, Business Information Technology Systems -> Deputy Technical Director, LoneStarCon 3 (http://lonestarcon3.org/) -> Sound Coordinator, Schenectady Light Opera Company ( http://www.sloctheater.org/ ) -> Technical Advisor, Troy Civic Theatre Company -> Technical Advisor, RPI Players