On 2017–03–06 and the day following that, a significant number (57) of tor relays joined the network, they all share the nickname prefix “UbuntuCore”.

In March 2017 over 290 such relays joined the tor network. This sparked my interest.

TLDR: As a tor user, you do not need to worry about them (yet), because they only make up a tiny part of the tor network (current total consensus weight fraction: <0.05%).

Update: As an example, this “UbuntuCore” relay group is about ten times smaller (by consensus weight fraction) than the (currently) biggest group of relays that you — as a tor user — should worry more about.

New “UbuntuCore” relays per day in March 2017:

By looking into OrNetRadar mailing list archives (non-onion URL) one can see that tor relays named “UbuntuCore”<number> appeared ever since the

Snap package “tor-middle-relay” was announced by its developer in May 2016 (2016–05–02).

Most (not all) of the May 2016 “UbuntuCore” relays were likely created by the developer testing the package (creating multiple relays on the same IP).

2016–12–10, the “starting” date?

The first time “UbuntuCore” named relays appeared with a suspiciously high geographical diversity was on 2016–12–10 (non-onion URL).

Six “UbuntuCore”<number> named tor relays from five different countries (FR, NO, RU, RS, IT) joined the tor network that day.

Since 2016–12–10 such relays continued to trickle in (5–9 relays per day, not every day) until it slowed down on 2017–02–06.

My guess is that this was caused by a change in the Snap on that day ( — enable-openbsd-malloc).

Once this change has been reverted (2017–03–06 17:13 UTC)

the (defunct?) “UbuntuCore” relays that were created between 2017–02–06 and 2017–03–06 became functional on 2017–03–06 and caused the spike of “new” relays (my guess).

(Note: Snaps apparently get updated automatically on a daily basis, which is good!)

The updated Snap package became available at 2017–03–06T17:45, 10 minutes later the developer updated his relay and all others followed

(onionoo data from 2017–03–06 23:00 UTC):

| first_seen | last_restarted | nickname |

| 2016–05–31 | 2017–03–06 17:55:20 | UbuntuCore160 |

| 2017–01–03 | 2017–03–06 18:12:02 | UbuntuCore160 |

| 2017–03–06 | 2017–03–06 18:13:39 | UbuntuCore161 |

| 2017–03–06 | 2017–03–06 18:15:12 | UbuntuCore160 |

| 2017–03–06 | 2017–03–06 18:18:51 | UbuntuCore160 |

| 2017–03–06 | 2017–03–06 18:22:23 | UbuntuCore160 |

| 2017–03–06 | 2017–03–06 18:28:37 | UbuntuCore161 |

| 2017–03–06 | 2017–03–06 18:33:14 | UbuntuCore160 |

| 2017–03–06 | 2017–03–06 19:18:29 | UbuntuCore160 |

| 2017–03–06 | 2017–03–06 19:18:30 | UbuntuCore160 |

| 2017–03–06 | 2017–03–06 19:25:26 | UbuntuCore161 |

| 2017–03–06 | 2017–03–06 19:30:41 | UbuntuCore160 |

| 2017–02–08 | 2017–03–06 19:33:50 | UbuntuCore160 |

| 2017–02–08 | 2017–03–06 19:33:51 | UbuntuCore160 |

[…]

How many of theses “UbuntuCore” relays are actually concurrently running?

Running “UbuntuCore” relays per tor network consensus in March 2017: