blob_sidecars data missing

[YuXiaoCoder]

System information

Erigon version: erigon version 3.5.1-bed215a4

OS & Version: Linux

Erigon Command (with flags/config): /opt/ethmain/core/erigon --chain=mainnet --networkid=1 --datadir=/mnt/ethmain/node --prune.mode=archive --torrent.download.rate=64mb --http --http.addr=0.0.0.0 --http.port=8545 --http.vhosts=* --http.api=admin,eth,net,web3,debug,trace,txpool,erigon --trace.maxtraces=2000 --ws --ws.port=8546 --rpc.batch.limit=10000 --rpc.returndata.limit=1000000 --rpc.gascap=0 --rpc.txfeecap=0 --beacon.api.addr=0.0.0.0 --be acon.api.port=3500 --beacon.api.cors.allow-origins=* --beacon.api=beacon,builder,config,debug,events,node,validator,lighthouse --port=30303 --nodekey=/mnt/ethmain/node/nodekey --caplin.blobs-immediate-backfill --caplin.states-archive --ca plin.blocks-archive --caplin.blobs-archive --caplin.blobs-no-pruning

Consensus Layer: Caplin

Consensus Layer Command (with flags/config): No

Chain/Network: 1

Expected behaviour

Data can be obtained through the following interfaces.

curl -X GET http://127.0.0.1:3500/eth/v1/beacon/blob_sidecars/14670000

Actual behaviour

ErigonV3 actually returned empty data, but I used Prysm to return data.

{"data":[]}

Steps to reproduce the behaviour

Running an archive node from scratch

[lystopad]

@YuXiaoCoder , hi
is your node still syncing ?

[YuXiaoCoder]

@YuXiaoCoder , hi is your node still syncing ?

@lystopad Node is synchronizing normally.

[domiwei]

Hi @YuXiaoCoder,

Slot 14670000 does have 3 blobs (verified against a public Beacon API), so the empty response is unexpected.

Could you help narrow this down?

1. Try the same request again now — is it still returning empty? If the node has been running for a while it may have caught up already.
2. If still empty, check the logs and share the output:

   # Blob backfill progress — is it still downloading?
   grep "BlobHistoryDownloader" /path/to/erigon.log | tail -20
   
   # Frozen blob snapshot coverage — "blobs-static" shows how far snapshots cover
   grep "Caplin.*Stat" /path/to/erigon.log | tail -5

3. Share the output — this should tell us whether backfill has reached slot 14670000 yet.

If it turns out backfill is still in progress, this is more of a UX issue — the API should probably indicate that the data is not yet available rather than returning an empty response.

[YuXiaoCoder]

@domiwei

I first upgraded the version to 3.5.2.

curl -X GET http://127.0.0.1:3500/eth/v1/node/version
{"data":{"version":"Caplin/3.5.2-8a829d21 linux/amd64"}}

I tried the same request again, and it still returned empty.

curl -X GET http://127.0.0.1:3500/eth/v1/beacon/blob_sidecars/14670000
{"data":[]}

The observation log shows there are too few peers.

cat /mnt/ethmain/log/supervisor_eth.log | grep "BlobHistoryDownloader"

[WARN] [07-14|14:51:11.291] [BlobHistoryDownloader] Skipping iteration due to low peer count peers=15 required=16
[WARN] [07-14|14:51:23.292] [BlobHistoryDownloader] Skipping iteration due to low peer count peers=13 required=16
[WARN] [07-14|14:51:35.292] [BlobHistoryDownloader] Skipping iteration due to low peer count peers=11 required=16
[WARN] [07-14|14:51:47.293] [BlobHistoryDownloader] Skipping iteration due to low peer count peers=13 required=16
[WARN] [07-14|14:51:59.294] [BlobHistoryDownloader] Skipping iteration due to low peer count peers=12 required=16

cat /mnt/ethmain/log/supervisor_eth.log | grep "Caplin.*Stat"

[INFO] [07-14|14:39:44.852] [Caplin-Archive] Historical States reconstruction slot=6873433 blk/sec=22.28
[INFO] [07-14|14:40:45.029] [Caplin-Archive] Historical States reconstruction slot=6874624 blk/sec=19.85
[INFO] [07-14|14:49:05.438] [Caplin] Stat                            blocks-static=14679999 states-static=0 blobs-static=14670000 state-history-enabled=true block-history-enabled=true blob-history-enabled=true snapgen=false
[INFO] [07-14|14:51:33.268] [Caplin-Archive] Historical States reconstruction slot=6859965 blk/sec=18.60
[INFO] [07-14|14:52:33.232] [Caplin-Archive] Historical States reconstruction slot=6861130 blk/sec=19.42
[INFO] [07-14|14:53:33.231] [Caplin-Archive] Historical States reconstruction slot=6862356 blk/sec=20.43
[INFO] [07-14|14:54:33.242] [Caplin-Archive] Historical States reconstruction slot=6863706 blk/sec=22.50
[INFO] [07-14|14:55:38.374] [Caplin-Archive] Historical States reconstruction slot=6864993 blk/sec=21.45
[INFO] [07-14|14:56:33.253] [Caplin-Archive] Historical States reconstruction slot=6866215 blk/sec=20.37

[VBulikov]

yperbasis added Imp2 as Importance