# Fix Local DNS — Complete Guide

**Last Updated:** 2026-01-31  
**Document Version:** 1.0  
**Status:** Active Documentation

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**Issue:** `DNS_PROBE_FINISHED_NXDOMAIN` for explorer.d-bis.org, explorer.defi-oracle.io, and all endpoints.

**Cause:** Your device/network DNS (ISP, router, or cached) is not resolving these domains. Cloudflare and Google DNS resolve them correctly.

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## Quick Fix (Run This)

```bash
sudo ./scripts/fix-local-dns-hosts.sh
```

This will:
1. Add 21 domain entries to `/etc/hosts` → 76.53.10.36
2. (WSL) Set `/etc/resolv.conf` to use Cloudflare DNS (1.1.1.1, 1.0.0.1)
3. (WSL) Add `generateResolvConf = false` to `/etc/wsl.conf` so DNS persists

**Note:** If you can't use sudo, run without it to see the hosts entries — then add them manually with `sudo nano /etc/hosts`.

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## Domains Added

| Domain | Purpose |
|--------|---------|
| explorer.d-bis.org | Blockscout explorer |
| explorer.defi-oracle.io | Explorer (alias) |
| rpc-http-pub.d-bis.org | RPC HTTP |
| rpc-ws-pub.d-bis.org | RPC WebSocket |
| rpc.d-bis.org, rpc2.d-bis.org | RPC aliases |
| ws.rpc.d-bis.org, ws.rpc2.d-bis.org | WebSocket aliases |
| rpc-http-prv.d-bis.org, rpc-ws-prv.d-bis.org | Private RPC |
| dbis-admin.d-bis.org, dbis-api.d-bis.org, etc. | DBIS services |
| mim4u.org, secure.mim4u.org, training.mim4u.org | MIM4U sites |
| rpc.public-0138.defi-oracle.io, rpc.defi-oracle.io, wss.defi-oracle.io | Defi Oracle RPC |

---

## Verify

```bash
# Should return 76.53.10.36
getent hosts explorer.d-bis.org

# Should return HTTP 200
curl -sI https://explorer.d-bis.org/ | head -3
```

---

## Alternative: Force Cloudflare DNS (No hosts file)

**WSL** — Create `/etc/wsl.conf`:
```ini
[network]
generateResolvConf = false
```

Then set `/etc/resolv.conf`:
```
nameserver 1.1.1.1
nameserver 1.0.0.1
```

Restart WSL: `wsl --shutdown` (from PowerShell), then reopen your terminal.

---

## Other Devices (Mobile, Windows, Mac)

- **Windows:** Settings → Network → DNS → Manual → 1.1.1.1, 1.0.0.1
- **Mac:** System Settings → Wi-Fi → Details → DNS → Add 1.1.1.1
- **iPhone:** Settings → Wi-Fi → (i) → Configure DNS → Manual → 1.1.1.1
- **Android:** Settings → Private DNS → dns.cloudflare.com

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**Last updated:** 2026-01-31