- tor-relays - lists.torproject.org

Guard flag flapping
by starlight.2015q3＠binnacle.cx 07 Aug '15

07 Aug '15

Both relays are showing low BWauth-measured bandwidth and are below the 2000 threshold for the Guard flag. Recently BWauths were offline and the consensus algorithm reverted to self- measure. During that period the relays were above the 2000 threshold and were assigned Guard. But even the self-measure was very low for a gigabit link in a tier-1 network (Quest). Some more tuning work is probably needed to get performance up higher. Possibly network issues are at work. If a low-end consumer-grade router or firewall is in the picture, it could be the cause of the problem.

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Guard flag flapping
by starlight.2015q3＠binnacle.cx 07 Aug '15

07 Aug '15

You might start with running SpeedTest via the Python script to see how the network performance looks: https://pypi.python.org/pypi/speedtest-cli/

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most hibernating relays wake up at the same time
by nusenu 07 Aug '15

07 Aug '15

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA512 Hi, most hibernating relays with daily quotas start relaying traffic at 0:00 local time. The timezone introduces some distribution but most relays are located in UTC +02:00 so most of them start relaying at 22:00 UTC. If you run a hibernating relay and want to spread your resources more evenly you can set a non-default AccountingStart time, simply choose HH:MM in that setting as you wish. (yes, AccountingStart != wakup time, but in practice it is the case for most hibernating relays with daily quotas) If someone has stats on when the tor network needs most bandwidth during the day it might makes sense to set AccountingStart accordingly - - to add bandwidth when most users need it. (but bw doesn't seem to be an issue currently..) Reference: https://trac.torproject.org/projects/tor/ticket/16723 -----BEGIN PGP SIGNATURE----- iQIcBAEBCgAGBQJVw9GgAAoJEFv7XvVCELh08iEP+wQ0F0+62ktQhR8fCFe+9yLS HacxpzLMG/4jDL0MmimVqCr5Ql9P05CXKzLse7ItEWNn5PlEkZ6z37DlQ9ctNgjY EwMlXZc1z+gLWRtHaWy6Yd0YUWkOfVfRu3bO2QDa5AN1/cEGv6+R8ddm1Ny2Mfem 5zMILOR3tofVNtpyFlahUQDEf2wQuZBMwmpYykD3I2+MfnOoeTe2AXHmgwtMdaNQ +CG+dEp8DueIYINqkYBWzmBZyTjtv3Z/ADHqyUDqFdwEsSWeC54Yb/2fZh1IEJub 383Zvhb4T3LRF2dUvKRFSCzTZl6FqZ4R1W2RvRV2Hg7xXtllbFUC/jY5i7zuJfe0 /aA5ZUv5+Rrqk7uOJpLaf6sXJGJBwCL1W5qDEtoZzQjHxbA8TFBQFYXtEfRUKiXA AiBFaJ+eLJlyztt38B6FxkN8auC25Y8csFtwcj25b8zykN4t+sFbrJvqy9r+dpzC klUlJuAlj3Oljjo4Ppd02k47yxmkc17e3TT5wm6tI2k8ZX7cD4GrK5ely+lxh/iz uceyEb7vphliJwt/slLQl9/wtg8dLvdIrpZ/rRO8uCVubSNodUuoyvuAtWn+xjsp BvwrCL0u6C/tkzRWR6OZPpuepnMk3vil9lNRkKuOadKnr2rihFb6qXgZg0RKpQDu IWCw2pXlUbbycW7K84Go =IYU/ -----END PGP SIGNATURE-----

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Guard flag flapping
by Green Dream 07 Aug '15

07 Aug '15

I have two relays on the same Gb/s connection. I followed the optimization tips offered in another thread, and think I have things running reasonably well. What I don't understand is why the Guard flag keeps flapping back and forth on both relays. https://atlas.torproject.org/#details/89B9AE4C778DE44AFFAB791093E19979616E6… https://atlas.torproject.org/#details/11A579CC6CEE644A390704977B70CBA8D8347… If you look at the 1 week graph of weights, you'll see what I mean. I haven't been able to find any documentation or explanation for this behavior. Anyone have any thoughts on why this might be happening, or any pointers on how to further investigate?

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longclaw BWauth is back, not measuring 2000 relays, what's with that?
by starlight.2015q3＠binnacle.cx 06 Aug '15

06 Aug '15

The explanation does help--thank you. Have been interested in how it would look after the script update since 7/28 (nine days ago) but did not realize it took so long to rebuild the data.

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longclaw BWauth is back, not measuring 2000 relays, what's with that?
by starlight.2015q3＠binnacle.cx 06 Aug '15

06 Aug '15

longclaw 4691 Measured values in w lines maatuska 6815 Measured values in w lines gabelmoo 6347 Measured values in w lines moria1 6715 Measured values in w lines

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BWauth no-consensus state in effect
by starlight.2015q2＠binnacle.cx 06 Aug '15

06 Aug '15

FYI list https://trac.torproject.org/projects/tor/ticket/16696 Description At present both 'longclaw' and 'maatuska' have dropped out of the BW consensus ('longclaw' is restarting with new version, not sure about 'maatuska'). This has caused the BW consensus logic to revert to using relay self-measurement for BW weightings due to fewer than three BW authorities participating. The 10000 cap placed on self-measure values is causing super-fast relays serious demotion and slower relays corresponding promotion in the consensus weighting. Possibly this may result in network unbalance issues. Some adjustment of the logic seems in order.

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Blutmagie does not see 0.2.7.2 bandwidth
by starlight.2015q3＠binnacle.cx 05 Aug '15

05 Aug '15

>At Tue Aug 4 11:22:22 UTC 2015 by Olaf Selke olaf DOT selke at blutmagie DOT de > >by the way... I will probably shut down blutmagie >tor network status in September this year cause >the data center has terminated the contract >housing my servers 10/31/15. Could you make your modified Torstatus code available on https://gitweb.torproject.org/torstatus so that someone else can set up another like it? Blutmagie appears to have significant and desirable enhancements to the code presently in the GIT repository. I might contribute a new Torstatus, but if not me someone surely will.

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BWauth no-consensus state in effect
by starlight.2015q3＠binnacle.cx 05 Aug '15

05 Aug '15

Maybe geo-location would not be so great because two networks in the same physical area might have relatively poor connectivity to each other. Aggregated IP block might be the ticket. CIDR-Report has both actual and suggested netblock aggregations. http://www.cidr-report.org/as2.0/#Gains Shows 562259 reduced to 253420 advertisements. Perhaps too fine-grained, but 250k is not so much bigger than the 45k ASN count. Idea is to anchor metrics to maximum size BGP routable blocks, which ought to correlate performance-wise down to all the IPs in each block. >>BWauths are continuously pairing relays for >>measurements, and perhaps metrics from that >>could be mapped to autonomous system numbers > >. . .scratch AS, geo-location is >better and MaxMind specializes in that > >Pinging a FiOS relay in LA takes >75ms while a close-by relay takes >8ms. Both are in AS 701.

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BWauth no-consensus state in effect
by starlight.2015q3＠binnacle.cx 05 Aug '15

05 Aug '15

>BWauths are continuously pairing relays for >measurements, and perhaps metrics from that >could be mapped to autonomous system numbers . . .scratch AS, geo-location is better and MaxMind specializes in that Pinging a FiOS relay in LA takes 75ms while a close-by relay takes 8ms. Both are in AS 701.

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BWauth no-consensus state in effect
by starlight.2015q3＠binnacle.cx 04 Aug '15

04 Aug '15

At Tue Aug 4 22:17:54 UTC 2015 by Mike Perry mikeperry at torproject dot org > >In some instances where I have not selected >my guards manually, Tor Browser is unbearably >slow. Like really, really painfully slow. >The whole time. Until I reinstall it. > >This makes me think that the performance of >people who pick guards from the tail is much >much worse than the performance of the top >guards, and this property likely is acting as >a deterrent to adoption. > Perhaps the guard-selection algorithm could be enhanced to consider some sort of distance/reachability metric generated by BWauths? BWauths are continuously pairing relays for measurements, and perhaps metrics from that could be mapped to autonomous system numbers (from MaxMind) in a useful way without requiring tremendous effort? Matrix analysis comes to mind. If one's guard is on the other side of the world, network latency and random congestion will hurt. I've read some path selection research is under way with an eye toward reducing passive traffic correlation exposure--this seems like it would help performance in a similar way.

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BWauth no-consensus state in effect
by starlight.2015q3＠binnacle.cx 04 Aug '15

04 Aug '15

Many under-utilized and never-utilized exits relays back online with BWauth outage. Unscientific sample out of 234 previously Unmeasured=1 exit relays, but almost all of the ones checked are like these https://atlas.torproject.org/#details/0D7739DEF50470356744440435FED9E1F57EF… https://atlas.torproject.org/#details/1E014CF541F32F377A116E78B76A603B8346A… https://atlas.torproject.org/#details/2316E6F012ACA52FDB09C745B0F5B41E78C23… https://atlas.torproject.org/#details/2A63402166192D66018D3FCB1ED8DE740CE71… https://atlas.torproject.org/#details/37C49200E04C8FE70799430718B10CEA5DBFB… https://atlas.torproject.org/#details/47BDCB56A9CCDAAAA71D74549E388C8EA1265…

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BWauth no-consensus state in effect
by starlight.2015q3＠binnacle.cx 04 Aug '15

04 Aug '15

Poking around Blutmagie, I suspect the number of relays with chopped bandwidth weightings might be more like in the range of 25-45. Perhaps the PID-controller algorithm should be adjusted to bias somewhat less toward super-fast relays.

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BWauth no-consensus state in effect
by starlight.2015q3＠binnacle.cx 04 Aug '15

04 Aug '15

At Tue Aug 4 20:16:17 UTC 2015 by Jannis Wiese mail at janniswiese.com >Strange thing: My relay [0] is speeding up since then >significantly (finally!!) That's because with no BWauth quorum the consensus algorithm reverts to using self-measured bandwidth with a ceiling of 10000. This causes the weight super-fast relays to drop substantially and provides a corresponding boost to middle and slower relays. Also puts most of the 450 Unmeasured=1 relays back in the game. In addition, this state eliminates all the crazy-stupid-buggy behavior of the BWauths that has been vexing operators so much. Only losers are the folks with huge bandwidth + CPU + tweaking in their relays, but the drop is not all that terrible. I've been watching this for two-plus days now and the Tor network rather runs better this way. Looks like no more than 50-100 relays are in the category where the weight is cut substantially, and plenty of unused capacity exists in the other 3000 or useable relays to make up the difference. Unfortunately the BWauths will likely be back due to the problem of adversarial gaming of the self-measure values. Even with a cap of 10000 someone will figure out ways to abuse the old pre-2009 approach of balancing the network. One can only hope that enough of the bugs have been worked out that BWauths will be behaving better going forward.

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Blutmagie does not see 0.2.7.2 bandwidth
by starlight.2015q2＠binnacle.cx 04 Aug '15

04 Aug '15

FYI list https: // torstatus DOT blutmagie DOT de is registering relays running 0.2.7.2 as having zero bandwidth. I believe this is because the write-history read-history lines in extra-info have moved from the top down to the middle of the document. Many super-fast relays running 0.2.7.2 are showing zero bandwidth and have dropped to the bottom of the ranking as a result. Might be a bug in 'metrics-db' or it might be a bug in a Blutmagie customization. Seems that the code at https://gitweb.torproject.org/torstatus.git/ retrieves advertised (self-measure) bandwidth rather than consumed bandwidth, so it's hard to say without a deep-dive into the code. I'm going by the fact that the new https://torstatus.rueckgr.at/index.php?SR=Bandwidth&SO=Desc shows advertised bandwidth and presumably runs code from the GIT repository. Sent an e-mail to Olaf Selke advising him of this issue. Not sure if he still maintains it, but the message did not bounce.

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Re: [tor-relays] Blutmagie does not see 0.2.7.2 bandwidth
by torrry＠Safe-mail.net 03 Aug '15

03 Aug '15

> debugging the old Blutmagie Perl scripts I found all routers like > splitDNA running Tor 0.2.7.2 sending two hash values in the > extra-info-digest. I suppose this isn't expected by the script parsing > the data. > > GETINFO desc/name/splitDNA > 250+desc/name/splitDNA= > router splitDNA 62.210.82.44 21 0 143 > [...] > extra-info-digest D6F7A98078BDA327D388D918EBA92D0FC9EDC487 > nMA7WhPSpQmquUdYpwIdQtdcKvTAcvNDnXleiPBia0U It shouldn't be expected by the script: https://gitweb.torproject.org/torspec.git/tree/dir-spec.txt ------------------------------------------------------------------ "extra-info-digest" digest NL [At most once] "Digest" is a hex-encoded digest (using upper-case characters) of the router's extra-info document, as signed in the router's extra-info (that is, not including the signature). (If this field is absent, the router is not uploading a corresponding extra-info document.) ------------------------------------------------------------------- Fetching descriptors via: http://<DIR_SERVER>/tor/server/all has 2 values for extra-info-digest as well.

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Re: [tor-relays] relay's count handshake versions, why not TLS handshake types?
by starlight.2015q2＠binnacle.cx 02 Aug '15

02 Aug '15

At 08:26 8/2/2015 -0700, you wrote: >I wonder if you could just run sslyze (or another >TLS scanning tool) on the OR ports of all the >relays, and see what ciphersuites they accept. The info would be indicative, but it would not reflect client-only Tor, which represents the majority of installations. Is why I think collecting connection statistics a good idea.

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Re: [tor-relays] relay's count handshake versions, why not TLS handshake types?
by starlight.2015q2＠binnacle.cx 02 Aug '15

02 Aug '15

Of course! This is implicit in my posting. What I am saying is that, like old v1/v2 handshakes, Tor should be moving in the direction of eliminating DHE. The way to approach that is to *count* the number of DHE handshakes and other TLS session attributes. This is currently begin done for TOR/NTOR handshakes but is not for TLS negotiations. 0.2.7 will not build/run with openssl 0.9.8, so once 0.2.7 is widely deployed DHE can be forcibly disabled. BUT, as with v1/v2 handshakes, one would not want to do that prematurely so counting them is a good idea. That suggesting is the principle idea of the thread. At 20:01 8/2/2015 +0300, you wrote: >I think that is to maintain a backward >compatibility. Tor tries as hard as possible to >maintain backward compatibility with older >versions, unless something critical which requires >deprecation regardless some relays will disappear >from the consensus. > >I guess this is the reason we currently prefer >ECDHE but do not reject DHE. In the future, when >we are certain everyone upgraded to new enough >OpenSSL, we can safely reject DHE all the time. >

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Re: [tor-relays] relay's count handshake versions, why not TLS handshake types?
by starlight.2015q2＠binnacle.cx 02 Aug '15

02 Aug '15

At 08:26 8/2/2015 -0700, you wrote: >It also may not tell you their ordering >preference (but it might! again, >you'd have to look at the code.) That "openssl s_client" test I ran was against my 0.2.6.10 with openssl 1.0.2 relay. It's certain that ECDHE is preferred over DHE, but my thought is that, especially with 0.2.7 dropping openssl 0.9.8 (no ECDHE), that relays should refuse to accept DHE connections entirely. We've seen many downgrade attacks and who knows for certain if none remain buried in the openssl? Seems prudent to kill-off DHE.

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relay's count handshake versions, why not TLS handshake types?
by starlight.2015q2＠binnacle.cx 02 Aug '15

02 Aug '15

In the next-above thread I had mistakenly conflated relay handshakes and 'openssl' TLS negotiations, which are it seems entirely independent. Thanks to Yawning for correcting that misconception. TLS encryption protects the relay-to-relay conversation protocol if I understand correctly, while cells are further encrypted with EC curve 25519 for the actual layered/onion encryption. Per ticket https://trac.torproject.org/projects/tor/ticket/15212 relay handshake types are counted and logged in the heartbeat message with the idea that the old v1/v2 handshake support should soon be eliminated soon. Now I wonder why the TLS handshake types are not also counted with the idea that DHE-RSA-AES256-SHA should be eliminated entirely due the near certainty that the NSA can decrypt any such sessions negotiated using the default DH 1024 bit primes, per the LogJam research https://weakdh.org/ I know that 0.2.7 is eliminating 'openssl' 0.9.8 from the picture, but this does not prevent $ openssl s_client -connect addr:port -tls1 -cipher EDH from successfully establishing a connection to relay OR ports with the aforementioned suspect DHE encryption level. Seems to me forcible prevention of this level of TLS session should be nearly as important as moving to the new ed25519 identity keys. In addition to ECDHE vs DHE, it might make sense to count how many SSL 3, TLS 1.0, 1.1 and 1.2 connections are established to be certain SSL 3 is really dead and to see how quickly TLS 1.2 is fully supported everywhere. Perhaps which ECDHE curve is selected should also be tracked.

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Tor 2.6.10 fails to generate fresh DH Keys
by starlight.2015q2＠binnacle.cx 02 Aug '15

02 Aug '15

>Bug: Assertion r == 0 failed in crypto_generate_dynamic_dh_modulus at ../src/common/crypto.c:1788. > Looks like you have DynamicDHGroups enabled in your torrc file. This is interesting because the recent LogJam research indicates the NSA has probably broken commonly used 1024 bit DH groups, which suggests turning on this parameter. However it was disabled by default some time ago for anti-fingerprinting reasons: https://trac.torproject.org/projects/tor/ticket/5598 AND, it's probably a moot issue now that Ntor handshakes (elliptic curve) have overtaken older RSA connections. So you should delete DynamicDHGroups 1 from torrc and let it be disabled by default.

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Tor 2.6.10 fails to generate fresh DH Keys
by cyb3rwr3ck 01 Aug '15

01 Aug '15

Hi there, after a unsuspected reboot of wr3ck3d0ni0n01 I decided to refresh all the keys. I took the chance to upgrade to 2.6.10 (Debian) and recognized that the relay wont start afterwards. It looks like it is unable to generate the new krypto: Aug 01 11:56:01.000 [notice] Tor 0.2.6.10 (git-71459b2fe953a1c0) opening log file. Aug 01 11:56:01.000 [notice] Generating fresh dynamic DH modulus. This might take a while... Aug 01 11:56:01.000 [err] tor_assertion_failed_(): Bug: ../src/common/crypto.c:1788: crypto_generate_dynamic_dh_modulus: Assertion r == 0 failed; aborting. Aug 01 11:56:01.000 [err] Bug: Assertion r == 0 failed in crypto_generate_dynamic_dh_modulus at ../src/common/crypto.c:1788. Stack trace: Aug 01 11:56:01.000 [err] Bug: /usr/bin/tor(log_backtrace+0x41) [0x7f892b3b3601] Aug 01 11:56:01.000 [err] Bug: /usr/bin/tor(tor_assertion_failed_+0x9f) [0x7f892b3c0def] Aug 01 11:56:01.000 [err] Bug: /usr/bin/tor(crypto_set_tls_dh_prime+0x7db) [0x7f892b3cfb1b] Aug 01 11:56:01.000 [err] Bug: /usr/bin/tor(set_options+0x1ce5) [0x7f892b35ee25] Aug 01 11:56:01.000 [err] Bug: /usr/bin/tor(options_init_from_string+0x2d3) [0x7f892b35f503] Aug 01 11:56:01.000 [err] Bug: /usr/bin/tor(options_init_from_torrc+0x1ca) [0x7f892b35f81a] Aug 01 11:56:01.000 [err] Bug: /usr/bin/tor(tor_init+0x2e2) [0x7f892b2d1202] Aug 01 11:56:01.000 [err] Bug: /usr/bin/tor(tor_main+0x55) [0x7f892b2d23a5] Aug 01 11:56:01.000 [err] Bug: /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xfd) [0x7f8929bc2ead] Aug 01 11:56:01.000 [err] Bug: /usr/bin/tor(+0x362ad) [0x7f892b2cd2ad] I wasn’t able to find any known bugs regarding this behaviour. Anyone out there who has seen this before? Best regards! Felix

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Re: [tor-relays] what is guard flag recovery time for outage?
by starlight.2015q2＠binnacle.cx 31 Jul '15

31 Jul '15

Ended up reading rephist.c for awhile. Seems the up/down time is accumulated with downtime discounted %5 every 12 hours. So absolute worst-case age-out for 100% downtime would be something like .95 ^ 76 (35.5 days) to get down it to 2%. Since the outage is not as bad as that, the guard flag should show up sooner. Not interested enough to calculated the exact answer. Will just watch it.

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what is guard flag recovery time for outage?
by starlight.2015q2＠binnacle.cx 31 Jul '15

31 Jul '15

Does anyone know how long it takes for the guard flag to come back after a multi-day relay downtime? Know that WTU (weighted time up) is 98%, and new-relay TK (time known) minimum is eight days. Reading rephist.c the the WTU is calculated from uptime history but rather then spend awhile to fully understand it seemed worth asking. Presently watching a relay that has been around six weeks, has been down four days recently and five total, has 14-day 100% uptime, Globe- calculated 1-month uptime of 85% and 3-month uptime of 90%. Had guard a couple of times but has not seen it return after the last outage.

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my provider null routed my exit. advice?
by Christopher Yeager 31 Jul '15

31 Jul '15

Hello, I run a 100mb exit hosted at server.lu since sometime in late 2013. There have been a couple dozen abuse reports but normally they forward them to me to deal with and nothing much happens. However a week or so ago, while I was travelling, there was an abuse report that made them decide to file a ticket which then led to them suspending my IP as I 'ignored' it while I was gone. So now I'm trying to convince them to turn the system back on and they are pushing back, and after some back and forth they say they want me to run an exit policy consisting of ports 53, 80, and 443. I've been running the suggested reduced exit policy since day one and am very reluctant to pare it down further, and certainly not to just 3 ports. I wrote a short note explaining my point of view and I wonder if any of you would do me the courtesy of telling me if I am likely to convince them to let me leave the exit policy alone. I'm very willing to edit my response as required. I think it bears mentioning that I am several messages in and I did not get a good sense that whoever I am talking to understands Tor very well at all - I was repeatedly asked to find and block my customer, and told I must have logs if I provide a service, etc. I can show you the longer exchange if you think it might be helpful. Thanks in advance and here goes: --- Hello, We have nothing against Tor but IP is listed at 11 blacklists including Spamhaus ZEN. So we have to ask you block all ports except 80, 53 and 443 to prevent scan, spam and other infringing activity from your IP. Hope such proposal will be suitable for you. Regards, ROOT S.A. --- Hello again, I would rather not block any more ports that are already blocked. The system is already set up to use the reduced exit policy detailed at https://trac.torproject.org/projects/tor/wiki/doc/ReducedExitPolicy which allows as many Internet services as possible while still blocking the majority of TCP ports. Currently, the policy allows approximately 65 ports. I am reluctant to further reduce the ports because there is vastly more to the internet than just the world wide web. Email, chat, remote desktop, cache, and vpn services are all valid uses of the network that would not be allowed by such a restrictive exit policy. I'm also afraid that it will not help much in getting this IP off the various blocklists that it is on, as 2/3rds of the abuse reports I've been sent were due to traffic on ports 80 or 443. Several of the lists such as SECTOOR and Dans TOREXIT and related are simply reporting to the world that this system is a Tor node. The system is only in the Spamhaus Zen list due to its listing in the CBL for being "infected with, or is NATting for a machine infected with s_vawtrak" which is a Microsoft Windows virus that connected to their sinkhole IP on port 80. Being on blocklists is something that happens when you are running a Tor exit node and supporting Tor means putting up with them and explaining why Tor is worth supporting even though abuse is guaranteed to happen. Naturally if you require this change I will be forced to make it. I hope, however, that you can be persuaded that it is not helpful to Tor and will not solve the problem of abuse and blacklists even if it were. Thanks again. -- Thanks for getting this far. I await your replies with interest. :)

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