Defederation Investigator
defed.xyz
Discover who has defederated your Fediverse instance with the Defederation Investigator.

A few months ago I released the Defederation Investigator, a tool to verify the federation status of Lemmy instances. With this new update, I’ve expanded it to support multiple Fediverse softwares, including:

  • Mastodon
  • Misskey
  • Mbin
  • Pleroma & Akkoma
  • Friendica

This works both ways: you can verify which Mastodon (et al) instances have defederated your Lemmy instance, as well as check the federation status of an instance running any of the supported softwares.

Like most of my works, this tool is FOSS and available on my team’s GitHub.

Limitations

Many microblogging platforms, Mastodon included, offer admins the possibility of hiding their blocklists from the public. As it turns out many instances have chosen this approach, so the available information can be pretty limited at times.

Also, this update has increased the pool of instances from a couple hundred to over 2 thousand, so query times have increased significantly. You can reduce them by deselecting some softwares from the query page (hint: most fedi instances are Mastodon ones, so by deselcting them you’ll cut out over half of the pool).

What about Kbin?

To my knowledge, Kbin doesn’t share its federation status through an API like most softwares do. Furthermore, given recent events, I have little faith in the Kbin project. Instead, I chose to support its community driven fork: Mbin.

What about Peertube and Pixelfed?

I tried looking through their API docs and wasn’t able to find any endpoints sharing either federation or defederation statuses. If anyone is familiar with any of these softwares and has any ideas on what to do to retrieve such information feel free to contact me, I’d love to add support for both.

What about …?

Want more softwares? Feel free to propose them. I’d like for this tool to support as many projects as possible.

  • mulcahey@lemmy.worldEnglish
    1·
    6 months ago

    Thank you for this great tool!

    Is there a way I could use this to find a Lemmy instance that let’s me interact with desired instances? For example:

    • I want to participate in Instance A, B, and C.
    • A has defederated from B and C
    • can I generate a list of instances that let’s me interact with A, B, and C? Then I’ll move my account there.

    Thank you!

    • Nerd02@lemmy.basedcount.comOPEnglish
      1·
      6 months ago

      Yeah sure. Assuming you are only targeting Lemmy instances (other softwares make this a bit more complicated), A “can interact” with B if:

      • A hasn’t blocked B
      • B hasn’t blocked A
      • Neither A nor B are on allowlist. If either is on allowlist, it must have explicitly added the other one to its allow list (this is very uncommon, the only big instance using allow lists is hexbear.net)

      So, to verify this, you could query the Defed Investigator with the instances you care about, one at a time. Only select the softwares you care about (likely only Lemmy) to make the query faster. Say you wanted to verify the compatibility between lemmy.world and sh.itjust.works (just making an example). Go to https://defed.xyz/check?name=sh.itjust.works&software=lemmy

      • ✔ lemmy.world doesn’t appear in the “Instances defederated from sh.itjust.works” (this means .world hasn’t blocked SJW)
      • ✔ lemmy.world doesn’t appear in the “Instances defederated by sh.itjust.works” (this means SJW hasn’t blocked .world)
      • ✔ lemmy.world doesn’t appear among the “Instances not allowing sh.itjust.works” (this means .world isn’t on allowlist or, if it is, it has explicitly allowed SJW. Again, this is very uncommon)

      Also make sure the instance you are looking for isn’t among the “Instances that returned errors”, of course.

  • ɐɥO@lemmy.ohaa.xyzEnglish
    1·
    6 months ago

    Wouldnt it be smarter to query the blocked list on the backend like once a day instead of doing thousands of requests in users browsers?

  • gabe [he/him]@literature.cafeEnglish
    01·
    6 months ago

    Oh my God. This is really, really, REALLY bad. I know this looks like a useful tool but extending this to software that isn’t lemmy is going to make the rest of the fediverse enraged. Tools like these are used as active harassment vectors. Theres a reason why the other fediverse instances that make these tools are affiliated with kiwifarms. Seriously please consider disabling non-lemmy software interaction immediately!

    • Nerd02@lemmy.basedcount.comOPEnglish
      1·
      6 months ago

      I’m sorry could you please elaborate on why the rest of the Fediverse would be enraged, or how this could be used for harassment? I don’t think I follow. I’ll admit, I only interact with the Fediverse through Lemmy so maybe there’s some dynamics of the Masto-sphere I’m not picking up.

      My understanding is that Mastodon admins can choose to hide their /domain_blocks endpoint to either outside users or even to all non admins. (source), and as a matter of fact almost a thousand of the 1700 Mastodon instances I’m querying already do so, so really I can only get the federation status of the few hundred that remain.

      I think the admins that prefer not to show their defeds, in fear of harassment, are already hiding them, so it should be ok for me to query the remaining ones.