Bug: Electrs fails when bitcoind has blocksonly=1

[sezaru]

Describe the bug I have both bitcoind and electrs fully synced in my server. I wanted now to enable blocksonly=1 on bitcoind to limit the resources and bandwidth used by the node.

After enabling that option, electrs fails to connect and gives the following error:

2024-06-05T14:45:54.501Z WARN  electrs::electrum] RPC blockchain.estimatefee failed: failed to estimate fee: JSON-RPC error: RPC error response: RpcError { code: -32603, message: "Fee estimation disabled", data: None }

Electrs version v0.10.5

To Reproduce Steps to reproduce the behavior:

1. Configure and start bitcoind
2. Configure and start electrs
3. Wait sync of both servers to finish
4. Enable blocksonly=1 in bitcoind config
5. Connect with electrum client (I'm using 4.5.2)
6. The client will never connect succesfully and the server will start logging the error above

Expected behavior I expected that electrs would work fine with blocksonly=1 option since other electrum server (like Electrum Personal Server for example) seem to work fine with that option enabled

Configuration

electrs.toml

``` # The listening RPC address of bitcoind, port is usually 8332 # Connect to bitcoind container on Docker daemon_rpc_addr = "bitcoin:8332" # The listening P2P address of bitcoind, port is usually 8333 # Connect to bitcoind container on Docker daemon_p2p_addr = "bitcoin:8333" # Directory where the index should be stored. It should have at least 70GB of free space. db_dir = "/electrs/data/" # bitcoin means mainnet. Don't set to anything else unless you're a developer. network = "bitcoin" # The address on which electrs should listen. Warning: 0.0.0.0 is probably a bad idea! # Tunneling is the recommended way to access electrs remotely. electrum_rpc_addr = "0.0.0.0:50001" # How much information about internal workings should electrs print. Increase before reporting a bug. log_filters = "INFO" ```

bitcoind.conf

``` # [core] # Only download and relay blocks - ignore unconfirmed transaction blocksonly=1 # Set database cache size in MB; machines sync faster with a larger cache. Recommend setting to 4000 if RAM is available. dbcache=250 # Maintain a full transaction index, used by the getrawtransaction rpc call. txindex=1 # [network] # Maintain at most N connections to peers. maxconnections=64 # [rpc] # Accept command line and JSON-RPC commands. server=1 # Bind to given address to listen for JSON-RPC connections. This option is ignored unless -rpcallowip is also passed. Port is optional and overrides -rpcport. Use [host]:port notation for IPv6. This option can be specified multiple times. (default: 127.0.0.1 and ::1 i.e., localhost) rpcbind=0.0.0.0 # Allow JSON-RPC connections from specified source. Valid for are a single IP (e.g. 1.2.3.4), a network/netmask (e.g. 1.2.3.4/255.255.255.0) or a network/CIDR (e.g. 1.2.3.4/24). This option can be specified multiple times. rpcallowip=0.0.0.0/0 # Listen for JSON-RPC connections on this port rpcport=8332 # Username and hashed password for JSON-RPC connections. The field comes in the format: :$. RPC clients connect using rpcuser=/rpcpassword= arguments. You can generate this value at https://jlopp.github.io/bitcoin-core-rpc-auth-generator/. This option can be specified multiple times. rpcauth=... ```

System running electrs

• Deployment method: Docker
• OS name and version (docker image): mu373/docker-electrs

Electrum client Client name (if not upstream desktop Electrum) and version: 4.5.2

[Kixunil]

blocksonly=1 means no mempool, which means no way to estimate fee so what you're asking for is literally impossible.

I guess we should put it somewhere into documentation.