Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932068AbWKWAKc (ORCPT ); Wed, 22 Nov 2006 19:10:32 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757209AbWKWAKb (ORCPT ); Wed, 22 Nov 2006 19:10:31 -0500 Received: from emailer.gwdg.de ([134.76.10.24]:27795 "EHLO emailer.gwdg.de") by vger.kernel.org with ESMTP id S1757186AbWKWAKb (ORCPT ); Wed, 22 Nov 2006 19:10:31 -0500 Date: Thu, 23 Nov 2006 01:10:08 +0100 (MET) From: Jan Engelhardt To: Gunter Ohrner cc: linux-kernel@vger.kernel.org Subject: Re: Entropy Pool Contents In-Reply-To: Message-ID: References: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-Spam-Report: Content analysis: 0.0 points, 6.0 required _SUMMARY_ Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1781 Lines: 56 >Hi! > >(PEBKAC warning. I'm probably doing something dump. I just don't know >what...) > >I seem to have an entropy pool on a headless machine which is not nearly >empty (a common problem in this case, I know), but completely empty and >stuck in this state... > >Hornburg:~# cat /proc/sys/kernel/random/entropy_avail >0 You really must have bad luck with your entropy... 01:05 ichi:/home/k > cat /proc/sys/kernel/random/entropy_avail 3596 01:08 ichi:/home/k > dd if=/dev/urandom of=/dev/null bs=3596 count=1 1+0 records in 1+0 records out 3596 bytes (3.6 kB) copied, 0.00115262 seconds, 3.1 MB/s 01:08 ichi:/home/k > cat /proc/sys/kernel/random/entropy_avail 157 however that might be caused because I am in X, mouse moves, kernel compiles, etc. >Also causing disk activities doesn't help at all. (Two disks on a Promise >PDC20268 controller.) Disk activities are "somewhat predictable", like network traffic, and hence are not (or should not - have not checked it) contribute to the pool. Note that urandom is the device which _always_ gives you data, and when the pool is exhausted, returns pseudorandom data. >The system runs a rather ancient Debian Sarge 2.4 kernel: >Linux Hornburg 2.4.27-3-386 #1 Thu Sep 14 08:44:58 UTC 2006 i486 GNU/Linux [I have] No memories about a kernel this old. :> >However as the machine itself is also ancient, the 2.4 seems like a good >match. And also 2.4 ought to have a refilling entropy pool, doesn't it? > >Maybe someone can shed some light on what's happening here... -`J' -- - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/