Backwards behaviour for new relay

I recently started my first relay, sTORMUR, and I have noticed that its behaviour seems backwards to the expected. Namely:

  • Relay server started 1800Z 18 Oct, quiet first 12 hours, as expected.
  • After 12 hours at 0600Z 19 Oct traffic suddenly jumped to configured max (200KiB/s). Download varied 50-400 KiB/s and upload was constant at 200KiB/s. More upload overall than down by a noticeable amount (~15%)
  • Consensus weight started at 1, over next couple days it slowly increased to 14. But as consensus weight increased, traffic decreased until after day 2 traffic was barely a trickle.
  • Consensus has now stagnated at 14.
  • Bandwidth data shows for the first three days, but no bandwidth data points for last two days.

My first thought was that the initial surge was a throughput test from a bwauth. But Is it normal for a bwauth test to run for a day and a half and for in and out traffic to be unbalanced during one?

I’m surprised it works at all (The minimum requirements for a relay are 10 Mbit/s (Mbps)).
As for traffic spikes, it is probably because of various attacks targeting Tor network.

I was using BandwidthRate to limit speed to the amount of data I wanted to donate per month, and then BandwidthRateBurst was set to the full connection speed. This was a poor choice, and I’m now using accounting and letting the connection run full speed.

I don’t think the initial burst was an attack. Each bwauth sends a fixed amount of traffic through for its bandwidth test, and at 200KiB/s that made each auth’s bandwidth test take much more time. On top of that, the bwauths aren’t smart enough to know not to step on each other’s test - I think they just assume if they are each randomly testing at some point over the first 24 hours they won’t step on each other. But with the slower speed, I think 4 or 5 of them stacked on each other at the same time which just snowballed. This killed each one’s bandwidth assessment and pegged the connection for a day.

The bandwidth assessment was hopelessly poisoned by this, so I’ve fixed the configuration and re-keyed the relay to reset it.

Red Oaive via Tor Project Forum:

I recently started my first relay, sTORMUR, and I have noticed that its behaviour seems backwards to the expected. Namely:

  • Relay server started 1800Z 18 Oct, quiet first 12 hours, as expected.
  • After 12 hours at 0600Z 19 Oct traffic suddenly jumped to configured max (200KiB/s). Download varied 50-400 KiB/s and upload was constant at 200KiB/s. More upload overall than down by a noticeable amount (~15%)
  • Consensus weight started at 1, over next couple days it slowly increased to 14. But as consensus weight increased, traffic decreased until after day 2 traffic was barely a trickle.
  • Consensus has now stagnated at 14.
  • Bandwidth data shows for the first three days, but no bandwidth data points for last two days.

Actually, if you look at the history section on relay-search you see
bandwidth data points for you relay, although, granted, it’s not much.
But then a consensus weight of 14 is not much either…

My first thought was that the initial surge was a throughput test from a bwauth. But Is it normal for a bwauth test to run for a day and a half and for in and out traffic to be unbalanced during one?

No. It’s basically just a couple of second downloading a file.

Vort via Tor Project Forum:

I’m surprised it works at all (The minimum requirements for a relay are 10 Mbit/s (Mbps)).

I think what is meant here is the minimum requirement for running a
useful relay. If you really, really want to you can run relays
configured to less than 100KiB/s (and there are such relays in the network).

···

As for traffic spikes, it is probably because of various attacks targeting Tor network.

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Oh, and you can read up on bandwidth measurements a bit on our blog post from a couple of years back. As a bonus point you get a link to a blog post about research questions related to Tor, which talks among other things about challenges related to bandwidth measurement.

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