From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from sog-mx-2.v43.ch3.sourceforge.com ([172.29.43.192] helo=mx.sourceforge.net) by sfs-ml-1.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1QoZmU-0005g0-TS for bitcoin-development@lists.sourceforge.net; Wed, 03 Aug 2011 11:38:34 +0000 Received-SPF: pass (sog-mx-2.v43.ch3.sourceforge.com: domain of bluematt.me designates 208.79.240.5 as permitted sender) client-ip=208.79.240.5; envelope-from=bitcoin-list@bluematt.me; helo=smtpauth.rollernet.us; Received: from smtpauth.rollernet.us ([208.79.240.5]) by sog-mx-2.v43.ch3.sourceforge.com with esmtps (TLSv1:AES256-SHA:256) (Exim 4.76) id 1QoZmS-0003Bv-F6 for bitcoin-development@lists.sourceforge.net; Wed, 03 Aug 2011 11:38:34 +0000 Received: from smtpauth.rollernet.us (localhost [127.0.0.1]) by smtpauth.rollernet.us (Postfix) with ESMTP id 09A62594033 for ; Wed, 3 Aug 2011 04:38:12 -0700 (PDT) Received: from mail.bluematt.me (unknown [IPv6:2001:470:9ff2:2:20c:29ff:fe16:f239]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) (Authenticated sender: @bluematt.me) by smtpauth.rollernet.us (Postfix) with ESMTPSA for ; Wed, 3 Aug 2011 04:38:11 -0700 (PDT) Received: from [IPv6:2001:470:9ff2:1:2c0:caff:fe33:858b] (unknown [IPv6:2001:470:9ff2:1:2c0:caff:fe33:858b]) by mail.bluematt.me (Postfix) with ESMTPSA id 95EBF261A for ; Wed, 3 Aug 2011 13:38:19 +0200 (CEST) From: Matt Corallo To: bitcoin-development@lists.sourceforge.net In-Reply-To: References: Content-Type: multipart/signed; micalg="pgp-sha1"; protocol="application/pgp-signature"; boundary="=-/8k+369dKwStOZeaoEy6" Date: Wed, 03 Aug 2011 13:38:19 +0200 Message-ID: <1312371499.2322.14.camel@Desktop666> Mime-Version: 1.0 X-Mailer: Evolution 2.32.2 X-Rollernet-Abuse: Processed by Roller Network Mail Services. Contact abuse@rollernet.us to report violations. Abuse policy: http://rollernet.us/abuse.php X-Rollernet-Submit: Submit ID 3205.4e393323.4677b.0 X-Spam-Score: 0.2 (/) X-Spam-Report: Spam Filtering performed by mx.sourceforge.net. See http://spamassassin.org/tag/ for more details. 1.7 URIBL_WS_SURBL Contains an URL listed in the WS SURBL blocklist [URIs: bitcoin.org.uk] -1.5 SPF_CHECK_PASS SPF reports sender host as permitted sender for sender-domain -0.0 SPF_HELO_PASS SPF: HELO matches SPF record -0.0 SPF_PASS SPF: sender matches SPF record X-Headers-End: 1QoZmS-0003Bv-F6 Subject: Re: [Bitcoin-development] DNS seeds returning gone peers X-BeenThere: bitcoin-development@lists.sourceforge.net X-Mailman-Version: 2.1.9 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 03 Aug 2011 11:38:35 -0000 --=-/8k+369dKwStOZeaoEy6 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Wed, 2011-08-03 at 12:04 +0200, Mike Hearn wrote: > This is expected to happen from time to time of course as it's > inherently racy, but there are a lot of bad nodes appearing in the DNS > seeds. > $ nmap -oG /tmp/x -p 8333 `dig +short bitseed.bitcoin.org.uk > dnsseed.bluematt.me bitseed.xf2.org` > ... > Nmap done: 48 IP addresses (25 hosts up) scanned in 9.80 seconds > $ grep -c 'closed' /tmp/x > 6 > So of 48 IPs returned only 19 are actually usable. This is slowing > down peer bringup for the Android apps, which don't currently save the > addresses of last-used peers (yes, I know we should fix this). Its actually much, much less. You forgot to grep for filtered, which are also worthless and you didn't make an actual connection to the node, meaning there is no way to tell if the node has its connection slots full (a node which has the maximum connection count will ack a syn, but will drop the connection after the first message, so nmap thinks the port is open). I just tested and I show 0 accepting from bitseed.xf2.org and 0 from bitcoin.bitcoin.co.uk. dnsseed.bluematt.me rotates every 2 minutes to the most recently checked so it tends to be pretty good if you get it right after a rotate, if you wait to long, those slots fill up quick. >=20 > I was talking to a friend a few days ago about Bitcoin, he seemed > interested. I'm hoping he might take on DNS seeding as a project. A > custom DNS server that watches the network to find long-lived peers > that run the latest version would be helpful for resolving this kind > of thing. Point him to https://github.com/TheBlueMatt/dnsseed it could use a bit of cleanup, but it works. If a different DNS Server were used to could pull directly from the database in a more dynamic way it would probably work better too (it was originally set up on MySQL and PowerDNS, but that is quite a resource hog compared to SQLite and BIND, but the original backend is still there and could work if you have a beefy enough server). Matt --=-/8k+369dKwStOZeaoEy6 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) iQIcBAABAgAGBQJOOTMgAAoJEBrh01BD4I5U9pUQAJlu7uDBrTZz7uPma5sReCe4 8jfLCbbOcmL5aU21N0VK2fye5yqSzGD5R9hn2pFPz0tT6osHHACbrHVbPaKCOsgp pWmxApOJlAbMJhPFITqzKcExmfhvVUKMo3q3T25MBSHEqXUQCQExLFFBZOEyXNrj HZ+ALk6FkSenBYaZ8Q4EIytiUv5kt0n+eWTnhgWeN75E9Ye9+NfWQFPSlL3BD68s U1d/cxTIzMuI6+LETKtpz3PIbLg4RQqTLMWWEUW9GuScSVM0Qfu/Hwt9pypbM2Ia AV06dIfnEDahYbnqzs+0EJNjjaBdKI6LczASUgMbptuv1hsn+l9ZSmGObnNdvpj1 K9NvSQnVFREcddcSuMsNQOlQuevGQ+/ZK/p8suUqDcn/Z+eMKPzPTTeA/aWMMPwr hGdSI0pyMyMOUKeU5VhbTJsVCXoc4y5XM/PRm8tb3DFzNqRJ4H6hI09hSrJyUOHL tih73jGeiGKaNaNkLoi0vL/MJln5dtkOvDtG+md1KVGtMv8Dd7n5QePCe9yDK/Bv qVrBEWkUyD8ZFGM8l/IEIWcdcBsH5J37p3bkJrx14GcszQ3PyGSuwdE2m0JeqSsk XmTzojIai05GfdeChQlP4YMobE3IjgSibuKVdN5jXoDNC5BW6tCV1vD1nkAt7BvC jBpEvXQhQx/A/mbqGpVp =dULe -----END PGP SIGNATURE----- --=-/8k+369dKwStOZeaoEy6--