- tor-relays - lists.torproject.org

Re: [tor-relays] Negative impact of MaxOnionsPending 250?
by Scott Bennett 31 Jul '12

31 Jul '12

On Thu, 26 Jul 2012 17:11:17 +0200 Moritz Bartl <moritz(a)torservers.net> wrote: >We sometimes see "Your computer is too slow to handle this many circuit >creation requests!" on our servers. Scott Bennett suggested to set >MaxOnionsPending to 250 instead of the default of 100, which at least >makes the warnings disappear. [1] > >I am thinking about modifying out torrc template we use as as basis for >all servers. What is the negative impact of setting MaxOnionsPending to >250? Should we instead reduce the bandwidth as suggested in the warning? I don't think so. To the best of my recollection, I've only seen this message in recent versions of tor when it appeared that my node had been chosen for one or more high-volume hidden service operations, where the traffic volume in B/s was still fairly low, yet the number of connections had suddenly climbed to an unusually high level. The data throughput capacity vastly exceeded the actual traffic, but the onionskin-decoding load was sometimes, but probably not continually, very high until the hidden service(s) either shut down or changed their advertised information in the hidden service directory. To lower my node's RelayBandwidth* values would most likely have little impact on the bottleneck. Raising MaxOnionsPending adds a little slack in the queue to handle the occasions where that activity is temporarily backlogged prevents dropped connections and allows operations to proceed normally with only minimal extra delays. Consider a delay of probably no more than a second at the outside and usually less versus the delay of building a new circuit to a hidden service due to a dropped connection. > >[1] https://lists.torproject.org/pipermail/tor-relays/2012-May/001352.html Scott Bennett, Comm. ASMELG, CFIAG ********************************************************************** * Internet: bennett at cs.niu.edu * *--------------------------------------------------------------------* * "A well regulated and disciplined militia, is at all times a good * * objection to the introduction of that bane of all free governments * * -- a standing army." * * -- Gov. John Hancock, New York Journal, 28 January 1790 * **********************************************************************

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Re: [tor-relays] Call for discussion: turning funding into more exit relays
by Zac Lym 30 Jul '12

30 Jul '12

This seems (to me) like an obvious suggestion, so my apologies if it's already been thought up. Why not establish a team/scoreboard system, like those used for distributed computing and BitCoin mining? This elegantly solves a few problems while with minimal resource commitment from the Tor organization. Most importantly, it's a way to pump money into the system without ruining the current atmosphere. Sponsors could easily buy some bandwidth or people can also just donate their own connections and join a particular team. The scoreboard is based on goodwill, not dollars spent. It also eliminates the hassle of setting prices, as teams can compete for dollars and bandwidth provided, essentially setting their own prices. The org could also setup a payment system, like we-pay, that the team admins can configure to deposit funds. It could be set as a proof of work system, paying after the bandwidth has been provided. This also allows a degree of control to prevent abuse from admins trying to juice stats by abusing some network infrastructure, like dummy trial accounts on hosting sites. A group admin could block specific hosts or the Tor project could remove an entire group. Finally, this could allow for the Tor project to create metrics based on things other than speed, akin to how Folding@home scores GPU and CPU contributions differently. Then the project can set anonymity goals for the network (such as location, ISP, backbone provider, etc) and the volunteers will adjust their patterns accordingly. Finally, I would like to strongly suggest taking a cut of all donations to pay for the new infrastructure and Tor research and development. I wouldn't want development to slow on Tor because donations are going to bandwidth instead. Indeed, I would prefer we spend a ton of money on the stenography efforts and usability. Anyway, thanks for the hard work! -Zach Lym

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nickname to fingerprint
by Aichetou Med 28 Jul '12

28 Jul '12

hello tor community my question is : is there an "easy" way to translate relay nickname to fingerprint ? if not is it possible to download descriptors for some specific relays given "Digest" string from consensus file? i mean before launching tor. besides is there a reason for not showing the fingerprint in the consensus. thank you :)

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Script to get top relays, AS and countries weights
by delber 27 Jul '12

27 Jul '12

Hi! Attached is a pretty simple Python script to compute some statistics about relays. Here's the doc: Usage: tor-relays-stats.py <output> [args ...] Where <output> is one of: - countries [FLAGS] relative percentage of the consensus in each countries - as-sets [FLAGS] [COUNTRIES] relative percentage of the consensus in each AS sets - top [COUNT] [FLAGS] [COUNTRIES] top relays according their place in the whole consensus Examples: - To get the top five exit nodes in France: tor-relays-stats.py top 5 Exit fr - To get weights of each AS of all relays in Germany: tor-relays-stats.py as-sets Running de Maybe it has flaws. Maybe it should land in some Git repository. I just felt it might be of interest to other folks. Feel free to comment and hack. -- delber

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Negative impact of MaxOnionsPending 250?
by Moritz Bartl 26 Jul '12

26 Jul '12

Hi, We sometimes see "Your computer is too slow to handle this many circuit creation requests!" on our servers. Scott Bennett suggested to set MaxOnionsPending to 250 instead of the default of 100, which at least makes the warnings disappear. [1] I am thinking about modifying out torrc template we use as as basis for all servers. What is the negative impact of setting MaxOnionsPending to 250? Should we instead reduce the bandwidth as suggested in the warning? [1] https://lists.torproject.org/pipermail/tor-relays/2012-May/001352.html -- Moritz Bartl https://www.torservers.net/

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High speed Relays/Exit nodes
by Dennis Ljungmark 26 Jul '12

26 Jul '12

Hi, We're currently running 6 different 100-200Mbit relay/guard nodes, and are looking at some issues moving on towards high performant exit nodes. There are some administrative issues ( needing another IP block due to the RIPE registration, our ISP doesn't want their name on the exit nodes that we are responsible for ) which are generally minor ( are being resolved anyhow ) and then the big stumbling block. Right now, with iptables modifications ( raw tables hacks to disable conntrack, bucket increases, following the general best practices ) our firewall is running at high amounts of CPU, but coping. However, once we start introducing Exit Nodes into this equation, things turn sour. So, since we do not want to trust only routing level separation between Exit Nodes and internal networks, we're going to have to invest into new hardware that can cope with this. Before this, we tried Ingate firewalls, and they weren't capable of coping with the load of guard nodes. ( The traditional "linux box in front" doesn't quite cut it due to networking hardware in most cases. ) So, in summary, when you get to the point of actively dealing with 8-900Mbps of Tor traffic ( on top of normal users and others) what hardware is needed to cope with firewalling? Regards, D.S. Ljungmark

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Call for discussion: turning funding into more exit relays
by Sriakhil Gogineni 26 Jul '12

26 Jul '12

Hello! I saw this posted on slashdot and think this is an excellent way to donate some of our time and expertise, especially considering Internet access has been declared a human right by the UN. We currently colocate with a provider and will be inquiring with them if they are OK with hosting Tor, (the post here: https://blog.torproject.org/blog/tips-running-exit-node-minimal-harassment was extremely helpful for other just joining and we will be following such advice when we bring it up with our provider). Ball park quotes we got were 99$ / 100 Mbps or $599 / 1000 Mbps for transit for a single 1U... we'll see if we can get something better... Would this be helpful / viable option for a Tor exit node ? I also had just one question: what are the specs required for a Tor node? It does not seem too resource intensive but I have not been able to find any minimum system requirements. Would a current / last-generation quad core with 8GB + would suffice? Best, Sri

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Paid exit nodes
by Brock Tice 25 Jul '12

25 Jul '12

Hi, I saw the story on Slashdot. I currently run an exit node (anfanillc) with a bandwidth limit. I have a decent uplink, though in bandwidth tests I see closer to 40 Mbps than 100 Mbps. I think $100/month would be plenty to defray the costs of removing the bandwidth limit. Maybe even less, I can talk with my ISP. I'm not charged for bandwidth right now, but my DC has to pay the ISP for it. I've already got my IP SWIPed and all that good stuff. Prior to this I've run exit nodes on and off for years without too much trouble, mostly DMCA takedowns. --Brock

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How many PK operations does a typical home-run relay or bridge do in 24 hours?
by Karsten Loesing 18 Jul '12

18 Jul '12

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hi relay and bridge operators, want to help us design hardware capabilities of a Torouter device? At the Florence hackfest I was asked for the typical number of RSA operations performed by a relay or bridge, say, per day. We're mostly interested in home-run relays and bridges on DSL lines and similar, because that's where Torouter devices will be deployed, too. So, Amunet and TorServers are out here. :) Tor has a built-in feature to count PK operations. If one sends a USR1 signal to the tor process, it writes a line like this to its log file (though this line comes from a client): Jul 10 18:31:22.904 [info] PK operations: 0 directory objects signed, 0 directory objects verified, 0 routerdescs signed, 2968 routerdescs verified, 216 onionskins encrypted, 0 onionskins decrypted, 30 client-side TLS handshakes, 0 server-side TLS handshakes, 0 rendezvous client operations, 0 rendezvous middle operations, 0 rendezvous server operations. The number we're most interested in is "onionskins decrypted," but maybe there are other high numbers that are worth considering. If you run a relay or bridge at home, run these four steps: 1. Make sure the relay or bridge is running for at least 24 hours (longer is fine, shorter may skew results) 2. Send the process a USR1 signal, e.g., kill -USR1 $pid 3. Look for the log line above 4. Reply to this email with a) the relay's or bridge's nickname, b) the first four hex characters of its fingerprint, c) the log time and timezone, d) the top-3 PK operations by numbers. An example result could be: gabelmoo F204 Jul 10 18:31:22.904 CEST 12345 onionskins decrypted 2968 routerdescs verified 216 onionskins encrypted Thanks for your help! Once I have some results, I'll look up relays and bridges in the descriptor archive and post results to this list. Of course, if someone has more thoughts on measuring how many PK ops a relay or bridge does, please say so! :) Thanks, Karsten -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (Darwin) Comment: GPGTools - http://gpgtools.org Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQEcBAEBAgAGBQJQAAjVAAoJEEk5d4GsWvIjWbMH/ilEf4dQrWqdFuZ5lYlWBnSb PAd/ru2ygGFswW4CeWWNKNnkxVd+Dcd9smVjVcpUIxlrEeMXzrZqsICre992Cjsd RjyXBnKIdwInwdVOi5ZyuWbmozCTbn5Oh3Bd47XFMDLNZIgC9itCdlGkU9Mw6bKB KO7QfbtQCTjlBEe/4mYmpW4/H+NaG5V8b3ByWtuAJz614cxckPgR2UxnEtYQXm7p TCRh/FC2jnc+7MrQZxBd6V6zLrudtdLCNLwdchGt7YBPMV3tyryvV6q/8v9ZY5jP VQTW6pKb5kVH1drL4M7oCJtt7bDnxhOGg76C7uBjWiXoaYUp4zyfeTdc57FkreM= =4Ex+ -----END PGP SIGNATURE-----

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Re: [tor-relays] SocksPort flags trouble
by Scott Bennett 17 Jul '12

17 Jul '12

On Tue, 17 Jul 2012 09:34:08 -0400 Nick Mathewson <nickm(a)freehaven.net> wrote: >On Tue, Jul 17, 2012 at 12:07 AM, Scott Bennett <bennett(a)cs.niu.edu> wrote: >> On Wed, 11 Jul 2012 11:33:52 -0400 Nick Mathewson <nickm(a)freehaven.net> >> wrote: >>>On Sun, Jul 8, 2012 at 4:19 AM, Scott Bennett <bennett(a)cs.niu.edu> wrote: >>>> While testing my torrc with 0.2.3.18-rc, I tried adding the >>>> IsolateDestAddr flag to the SocksPort line, as in >>>> >>>> SocksPort 9050 IsolateDestAddr >>>> >>>> A "tor --verify-config" claimed that I was trying to specify more >>>> than one port on that line, which would be an error. Are the SocksPort >>>> flags listed in the tor man page for 0.2.3.18-rc not yet implemented? >>> >>>Just tried it with 0.2.3.18-rc (as tagged in git), using only that >>>option. It worked for me. Could you have had some other tor in your >>>path as "tor", or something like that? >>> >> No. Here's sample output. >> >> Script started on Mon Jul 16 22:56:43 2012 >> >> [hellas] 74 % sudo -u _tor tor --verify-config >> Jul 16 22:57:03.186 [notice] Tor v0.2.3.18-rc running on FreeBSD. >> Jul 16 22:57:03.187 [notice] Tor can't help you if you use it wrong! Learn how to be safe at https://www.torproject.org/download/download#warning >> Jul 16 22:57:03.211 [notice] Read configuration file "/usr/local/etc/tor/torrc". >> Jul 16 22:57:03.256 [warn] SocksListenAddress can only be used with a single SocksPort with value "auto" or 1-65535. >> Jul 16 22:57:03.256 [warn] Failed to parse/validate config: Invalid SocksPort/SocksListenAddress configuration >> Jul 16 22:57:03.256 [err] Reading config failed--see warnings above. >> [hellas] 75 % exit >> exit >> >> Script done on Mon Jul 16 22:57:42 2012 >> >> Lines in torrc beginning with "Socks" are as follows. >> >> SocksPort 9050 IsolateDestAddr # what port to open for local application connections >> SocksListenAddress 127.0.0.1 # accept connections only from localhost >> SocksPolicy accept 127.0.0.1:* >> SocksPolicy accept 192.168.0.0/16:* >> SocksPolicy reject *:* >> > >The problem with that is nothing about the SocksPort: it's about the >SocksListenAddress. You can't use SocksListenAddress with the new >SocksPort format. Instead you would need to say: > >SocksPort 127.0.0.1:9050 IsolateDestAddr > Okay. Thanks for that. However, the message probably ought to be changed to avoid confusion. After all, I did have only one port specified, and it (9050) was in the range of 1-65535, which the message implies was untrue. Scott Bennett, Comm. ASMELG, CFIAG ********************************************************************** * Internet: bennett at cs.niu.edu * *--------------------------------------------------------------------* * "A well regulated and disciplined militia, is at all times a good * * objection to the introduction of that bane of all free governments * * -- a standing army." * * -- Gov. John Hancock, New York Journal, 28 January 1790 * **********************************************************************

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