majorwiki/02-selfhosting/services/mastodon-federation.md

---
title: Mastodon Federation — Domain Blocks, Silencing, and FediSeer
domain: selfhosting
category: services
tags:
  - mastodon
  - federation
  - fediverse
  - domain-blocks
  - fediseer
  - majortoot
status: published
created: 2026-04-22
updated: 2026-04-22
---

# Mastodon Federation — Domain Blocks, Silencing, and FediSeer

## Domain Block Severity — Critical Gotcha

The Mastodon admin UI labels severities as **Silence** and **Suspend**, but the integer values stored in the database are **not** in alphabetical order. The Rails enum is:

```ruby
# app/models/domain_block.rb
enum :severity, { silence: 0, suspend: 1, noop: 2 }, validate: true
```

| DB value | Meaning | Effect |
|----------|---------|--------|
| `0` | **silence** | Instance limited — posts hidden from public timelines; follows require manual approval |
| `1` | **suspend** | Full defederation — all content removed, all follows severed |
| `2` | **noop** | No effect — entry tracked but no federation action taken |

> [!warning] Don't trust raw integer queries
> If you query `domain_blocks` directly via psql, severity `0` looks like "the lowest level" but it's actually **silence** — a meaningful restriction. Always map through the enum. This tripped up a defederation investigation on 2026-04-22 where 13 silenced instances (including mastodon.social) were initially misread as noop.

### majortoot block inventory (as of 2026-04-22)

| Severity | Count | Notable entries |
|----------|-------|-----------------|
| silence (0) | 13 | mastodon.social, mastodon.world, chaos.social, fosstodon.org, tech.lgbt, threads.net |
| suspend (1) | 413 | Full defederation list |
| noop (2) | 0 | — |

---

## How Silencing Affects Follows

When your instance silences a remote domain, **every follow request from that domain requires manual approval** — even if your account has `locked = false`.

This is enforced in `app/lib/activitypub/activity/follow.rb`:

```ruby
if target_account.locked? || @account.silenced?
  LocalNotificationWorker.perform_async(target_account.id, follow_request.id, 'FollowRequest', 'follow_request')
```

`@account.silenced?` returns true when the sending account's domain is in your `domain_blocks` at severity=0. The follow goes to the follow_requests queue instead of being automatically accepted.

**Practical effect on majortoot:** mastodon.social is silenced (added 2026-12-11, same day as a FluentInFinance follow-spam report). All follows from mastodon.social accounts appear as pending follow requests requiring manual approval. This is intentional — it's the expected behavior of a silence block.

---

## Checking Defederation Status

### Are major instances blocking you?

Check if your domain appears in another instance's public block list:

```bash
# Check mastodon.social's public block list (397 entries as of 2026-04-22)
curl -s "https://mastodon.social/api/v1/instance/domain_blocks" | \
  python3 -c "import sys,json; data=json.load(sys.stdin); \
  found=[b for b in data if b['domain']=='toot.majorshouse.com']; \
  print('BLOCKED' if found else 'Not in public block list')"
```

Note: instances can mark blocks as private, so absence from the public list is not a guarantee.

### Are you in their peer list?

If you're in an instance's peer list, they've federated with you at some point:

```bash
curl -s "https://mastodon.social/api/v1/instance/peers" | \
  python3 -c "import sys,json; data=json.load(sys.stdin); print('toot.majorshouse.com' in data)"
```

### Is the account visible from a remote instance?

```bash
curl -s "https://mastodon.social/api/v1/accounts/lookup?acct=majorlinux@toot.majorshouse.com" | \
  python3 -c "import sys,json; d=json.load(sys.stdin); print('limited:', d.get('limited'), 'suspended:', d.get('suspended'))"
```

`limited: true` means the remote instance has silenced toot.majorshouse.com.

### Check federation delivery health (Sidekiq)

```bash
ssh root@100.110.197.17 "redis-cli llen sidekiq:dead; redis-cli llen sidekiq:retry"
# Both should be 0 for a healthy instance
```

### Check unavailable domains (delivery consistently failing)

```bash
ssh root@100.110.197.17 "
sudo -u postgres psql mastodon_production -c \
  'SELECT domain, updated_at FROM unavailable_domains ORDER BY updated_at DESC LIMIT 20;'"
```

These are domains where ActivityPub delivery has repeatedly failed. Most are dead instances, not active blocks.

---

## FediSeer Registration

[FediSeer](https://fediseer.com) is a community service that tracks censures (formal complaints) against fediverse instances. Registering lets you monitor if any instance formally censures toot.majorshouse.com.

### majortoot status (registered 2026-04-22)

| Field | Value |
|-------|-------|
| Domain | toot.majorshouse.com |
| ID | 5575 |
| State | UP |
| Censures received | 0 |
| Endorsements | 0 |
| Tags | mastodon, selfhosted, leftist, foss |
| Guarantor | none |
| API key | Bitwarden — "FediSeer — toot.majorshouse.com" |

### Claiming / re-claiming your instance

```bash
# Claim (sends API key via DM from @fediseer@fediseer.com)
curl -s -X PUT "https://fediseer.com/api/v1/whitelist/toot.majorshouse.com" \
  -H "Content-Type: application/json" \
  -d '{"admin": "majorlinux", "pm_proxy": "MASTODON"}'

# The API key arrives as a DM — delete the DM after saving to Bitwarden
```

### Check censures

```bash
curl -s "https://fediseer.com/api/v1/censures/toot.majorshouse.com" | python3 -c \
  "import sys,json; d=json.load(sys.stdin); print('Censures:', d.get('total',0))"
```

### Update tags

```bash
curl -s -X PUT "https://fediseer.com/api/v1/tags" \
  -H "Content-Type: application/json" \
  -H "apikey: <key-from-bitwarden>" \
  -d '{"tags_csv": "mastodon,selfhosted,leftist,foss"}'
```

---

## See Also

- [[Mastodon]] — service doc
- [[majortoot]] — server doc
- [[mastodon-db-maintenance]] — statuses remove, accounts cull, vacuum
- [[mastodon-instance-tuning]] — character limits, media cache