From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from sog-mx-4.v43.ch3.sourceforge.com ([172.29.43.194] helo=mx.sourceforge.net) by sfs-ml-3.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1QoaRB-0002xc-Hf for bitcoin-development@lists.sourceforge.net; Wed, 03 Aug 2011 12:20:37 +0000 Received-SPF: pass (sog-mx-4.v43.ch3.sourceforge.com: domain of lavabit.com designates 72.249.41.33 as permitted sender) client-ip=72.249.41.33; envelope-from=calebdelisle@lavabit.com; helo=karen.lavabit.com; Received: from karen.lavabit.com ([72.249.41.33]) by sog-mx-4.v43.ch3.sourceforge.com with esmtp (Exim 4.76) id 1QoaR9-000347-9Z for bitcoin-development@lists.sourceforge.net; Wed, 03 Aug 2011 12:20:37 +0000 Received: from d.earth.lavabit.com (d.earth.lavabit.com [192.168.111.13]) by karen.lavabit.com (Postfix) with ESMTP id DCA8B11BB93 for ; Wed, 3 Aug 2011 07:20:29 -0500 (CDT) Received: from 192.168.1.2 (pool-74-106-69-189.spfdma.east.verizon.net [74.106.69.189]) by lavabit.com with ESMTP id BDLW6WGRDUKR for ; Wed, 03 Aug 2011 07:20:29 -0500 Message-ID: <4E393EB9.9040005@lavabit.com> Date: Wed, 03 Aug 2011 08:27:37 -0400 From: Caleb James DeLisle User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:2.0b9pre) Gecko/20110109 Thunderbird/3.3a2pre MIME-Version: 1.0 To: bitcoin-development@lists.sourceforge.net References: <1312371499.2322.14.camel@Desktop666> In-Reply-To: <1312371499.2322.14.camel@Desktop666> X-Enigmail-Version: 1.2a1pre Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Spam-Score: -0.7 (/) 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_PASS SPF: sender matches SPF record -0.7 RP_MATCHES_RCVD Envelope sender domain matches handover relay domain -0.1 DKIM_VALID_AU Message has a valid DKIM or DK signature from author's domain 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily valid -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature X-Headers-End: 1QoaR9-000347-9Z 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 12:20:37 -0000 -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 08/03/2011 07:38 AM, Matt Corallo wrote: > 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. Someone I know who runs a moderately large website told me that some ISPs cache DNS for as long as a week without regard to TTL. If your DNS seeds are not pointing to your own dedicated boxen then you might want to do a lookup on a random cookie as a subdomain. Caleb >> >> 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 > > > > ------------------------------------------------------------------------------ > BlackBerry® DevCon Americas, Oct. 18-20, San Francisco, CA > The must-attend event for mobile developers. Connect with experts. > Get tools for creating Super Apps. See the latest technologies. > Sessions, hands-on labs, demos & much more. Register early & save! > http://p.sf.net/sfu/rim-blackberry-1 > > > > _______________________________________________ > Bitcoin-development mailing list > Bitcoin-development@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/bitcoin-development -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (GNU/Linux) iQIcBAEBAgAGBQJOOT64AAoJECYAmptlsgnWNNYP/3pk/61AOaTo8577XF2E3RWU hqPclOYMveBZveo7Hz0k/Vf3TMf5p7CFGtFllApVmmR5ck4hXwow+tXwaYvBuf9b 4QwDlNtBelZ+7DqOdDTxRjaRzBo7PlsuiEp+6B3+oggfjKWnkWlIighfM/6LOtMO kv+MsC9xulqCrX96FrQBERVknkvza8NWfVblAFCM0uxECC5Hd52W1Okx1cDqUsIj MAp6T6IDwy1u0WtYIZBbD3KR802tqTpx/gzElo2AAz4ZR8P9yATBbAjmd9vZDscB SRF5yg+BIAzTQzz84c0cno8Q6hFyieRLTu9x0AWUqAZPTL3OgYV7hyl9WXMzcQGY LgnG9hP5N9qn2S+rYJuNJwvTJhzaLgUwOdRgyisI8v86R5vEjOpAAPVStAgCtvw2 6BJJvit3iZ74fK37kPb4iEljd11ibb8rOoiZzKSuS6LMJXkCplQQ06Uhy9MFd/Wn UZbSwbXqizJmQUPnHfCvvJc9fmoPFbj4SpYagxXFbUXtQsuB84h1e/jKAf5cvRed n0fLfKBZJuAfK1B/lV8+R6+oJj6F2OSGdCpdGzMlrxKX3JPcDJGK56/JmFzaqXyA ScaYja4yps83l80zt7H9Fadl642tNWXsdETniyDt2ADnqr1u/nWr9m+aT7oskbZA SfO+U22w9JC0CW8u5fAa =7WNK -----END PGP SIGNATURE-----