None of the chainspec bootnodes are working

[jkbrsn]

Hello,

We've recently run into issues syncing our Mythos nodes, and have tracked it down to the chainspec files' bootnodes simply not working any longer.

For each multiaddr in chainspecs/mythos-raw.json's bootNodes list, we performed a liveness probe:

• /tcp/ endpoints: resolve the DNS name and attempt a TCP handshake to the advertised port.
• /wss/ (and /tls/ws/) endpoints: resolve the DNS name, complete the TLS handshake against the advertised port, then send an HTTP Upgrade: websocket request and expect 101 Switching Protocols.

This is intentionally a lower bar than a real libp2p connection — it does not perform the Noise handshake or Identify exchange, so a "pass" only means "reachable and speaks WS." That makes the failure modes below unambiguous: they fail well before any libp2p-level negotiation would even start.

Script output if interesting to know:

./polkadot-bootnode-checker.py --spec-url https://raw.githubusercontent.com/paritytech/project-mythical/refs/heads/main/chainspecs/mythos-raw.json
[FAIL] net: [Errno -5] No address associated with hostname /dns/polkadot-mythos-connect-0.polkadot.io/tcp/30333/p2p/12D3KooWJ3zJMjcReodmHx5KLm9LwbFtLvScncqj89UX5j8VYMUf
[FAIL] net: [Errno -5] No address associated with hostname /dns/polkadot-mythos-connect-0.polkadot.io/tcp/443/wss/p2p/12D3KooWJ3zJMjcReodmHx5KLm9LwbFtLvScncqj89UX5j8VYMUf
[FAIL] net: [Errno -5] No address associated with hostname /dns/polkadot-mythos-connect-1.polkadot.io/tcp/30333/p2p/12D3KooWLin9rPs8irgJZgFTab6nhQjFSVp6xYTPTrLGrbjZypeu
[FAIL] net: [Errno -5] No address associated with hostname /dns/polkadot-mythos-connect-1.polkadot.io/tcp/443/wss/p2p/12D3KooWLin9rPs8irgJZgFTab6nhQjFSVp6xYTPTrLGrbjZypeu
[FAIL] net: [Errno 113] Connect call failed ('104.247.178.10', 8710) /dns/boot.helikon.io/tcp/8710/p2p/12D3KooWJkp1w3AqnppvoZWvUv393PwaNA5MfDc1LceaLvqwZgwr
[FAIL] net: [Errno 111] Connect call failed ('104.247.178.10', 8712) /dns/boot.helikon.io/tcp/8712/wss/p2p/12D3KooWJkp1w3AqnppvoZWvUv393PwaNA5MfDc1LceaLvqwZgwr
[FAIL] net: [Errno 113] Connect call failed ('195.144.22.130', 11433) /dns/boot.metaspan.io/tcp/11433/p2p/12D3KooWQyZLieszShULfKAM6Ju9txiv2u9a6QYS5uQd1sEJc3HZ
[FAIL] timeout after 8.0s                       /dns/boot.metaspan.io/tcp/11436/wss/p2p/12D3KooWQyZLieszShULfKAM6Ju9txiv2u9a6QYS5uQd1sEJc3HZ
[FAIL] RuntimeError: WS upgrade rejected: 'HTTP/1.0 503 Service Unavailable' /dns/mythos-boot-ng.dwellir.com/tcp/443/wss/p2p/12D3KooWNXgPTbaAARxVMX9aSLygkqhcWqdbA318tyC3rdy4bgB2
[FAIL] net: [Errno 113] Connect call failed ('102.69.240.202', 30376) /dns/mythos-boot-ng.dwellir.com/tcp/30376/p2p/12D3KooWNXgPTbaAARxVMX9aSLygkqhcWqdbA318tyC3rdy4bgB2
[FAIL] timeout after 8.0s                       /dns/mythos-bootnode.radiumblock.com/tcp/30333/p2p/12D3KooWN2F6hiks7re1Y4pxQQvzCyrnCCX8vyhfRrU4xqky6LD5
[FAIL] timeout after 8.0s                       /dns/mythos-bootnode.radiumblock.com/tcp/30336/wss/p2p/12D3KooWN2F6hiks7re1Y4pxQQvzCyrnCCX8vyhfRrU4xqky6LD5

0/12 bootnodes reachable (shallow)