[Bug] Warp sync node block height frozen: unexpectedly transitions from Idle to Preparing (0.0 bps) for ~6 minutes without restart, coinciding with NetworkRemoved event

[553589912]

subtensor-mainnet-lite | 2026-05-06 09:59:41 💤 Idle (40 peers), best: #8123780 (0xc617…f940), finalized #8123779 (0x72d1…c4e4), ⬇ 21.1kiB/s ⬆ 22.6kiB/s
subtensor-mainnet-lite | 2026-05-06 09:59:46 💤 Idle (40 peers), best: #8123780 (0xc617…f940), finalized #8123779 (0x72d1…c4e4), ⬇ 32.7kiB/s ⬆ 22.1kiB/s
subtensor-mainnet-lite | 2026-05-06 09:59:51 💤 Idle (40 peers), best: #8123780 (0xc617…f940), finalized #8123780 (0xc617…f940), ⬇ 76.0kiB/s ⬆ 35.1kiB/s
subtensor-mainnet-lite | 2026-05-06 09:59:56 💤 Idle (40 peers), best: #8123780 (0xc617…f940), finalized #8123780 (0xc617…f940), ⬇ 31.0kiB/s ⬆ 27.5kiB/s
subtensor-mainnet-lite | 2026-05-06 10:00:01 💤 Idle (40 peers), best: #8123780 (0xc617…f940), finalized #8123780 (0xc617…f940), ⬇ 41.5kiB/s ⬆ 27.1kiB/s
subtensor-mainnet-lite | 2026-05-06 10:00:06 💤 Idle (40 peers), best: #8123780 (0xc617…f940), finalized #8123780 (0xc617…f940), ⬇ 52.5kiB/s ⬆ 48.7kiB/s
subtensor-mainnet-lite | 2026-05-06 10:00:11 💤 Idle (40 peers), best: #8123780 (0xc617…f940), finalized #8123780 (0xc617…f940), ⬇ 71.8kiB/s ⬆ 51.8kiB/s

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subtensor-mainnet-lite | 2026-05-06 10:06:16 ⚙️ Preparing 0.0 bps, target=#8123812 (40 peers), best: #8123780 (0xc617…f940), finalized #8123780 (0xc617…f940), ⬇ 71.6kiB/s ⬆ 2.3kiB/s
subtensor-mainnet-lite | 2026-05-06 10:06:21 ⚙️ Preparing 0.0 bps, target=#8123812 (40 peers), best: #8123780 (0xc617…f940), finalized #8123780 (0xc617…f940), ⬇ 47.8kiB/s ⬆ 2.5kiB/s
subtensor-mainnet-lite | 2026-05-06 10:06:21 NetworkRemoved( netuid:NetUid(26) )
subtensor-mainnet-lite | 2026-05-06 10:06:21 Failed to schedule children for root validator 82b9ad19799ddb1bf0c237ee5f0c4726d5c2ad27d71d2c276ee20d31b5391c37 (5F27Eqz2...) on netuid NetUid(26): Module(ModuleError { index: 7, error: [11, 0, 0, 0], message: Some("NotEnoughStakeToSetChildkeys") })
subtensor-mainnet-lite | 2026-05-06 10:06:21 Failed to schedule children for root validator e0dc10a5043be43cae0c4fe2ef713a4592e2a5fc6e2351e6ebffb852eb0ecc70 (5H9XxRFA...) on netuid NetUid(26): Module(ModuleError { index: 7, error: [11, 0, 0, 0], message: Some("NotEnoughStakeToSetChildkeys") })

Additional Evidence

• Two independent nodes with identical configurations
  stopped at the exact same block height simultaneously
• This rules out local hardware or network issues as the cause
• Blockchain explorer showed no anomalies during this period,
  meaning only warp sync + pruned nodes were affected

Questions

1. Is this a confirmed bug?
2. What triggers the transition from Idle → Preparing
   without a restart?
3. Does --sync=warp combined with --state-pruning have
   known issues when large on-chain state changes occur?
4. Is there a known workaround or fix planned?

[553589912]

2026-05-06 09:59:56 - 2026-05-06 10:06:21 on 8123780

[553589912]

cat docker-compose.yml
version: "3.8"

services:
mainnet-lite:
image: ghcr.io/opentensor/subtensor:v3.3.14-401
container_name: subtensor-mainnet-lite
ports:
- "8081:9944"
- "30333:30333"
- "9933:9933"
volumes:
- ./data:/data
command:
- --base-path=/data
- --chain=./chainspecs/raw_spec_finney.json
- --rpc-external
- --rpc-cors=all
#- --rpc-port 8081
- --no-mdns
- --bootnodes=/dns/bootnode.finney.chain.opentensor.ai/tcp/30333/ws/p2p/asdasdsaJzndoRrTDotTR5gDC
- --sync=warp
- --database paritydb
- --db-cache 4096
- --trie-cache-size 2048
- --blocks-pruning=150000
- --state-pruning=150000
environment:
- CARGO_HOME=/var/www/node-subtensor/.cargo

sidecar:
image: parity/substrate-api-sidecar:v20.14.1
container_name: mainnet-lite-sidecar
restart: always
ports:
- "8080:8080"
environment:
- SAS_SUBSTRATE_URL=http://mainnet-lite:9944
- SAS_EXPRESS_PORT=8080
depends_on:
- mainnet-lite