b10c · Just a network observations I wanted to write down. Nothing problematic.
While looking into peers sending us the same block multiple times in a short time-frame, I came across this interaction with a peer:
2026-04-20T17:57:23.83Z [msghand] [net] SendMessages: sending header 000000000000000000009143bbce4fcf339db8f66a9d742989db608d3d24e40c to peer=1389928
2026-04-20T17:57:23.83Z [msghand] [net] sending headers (82 bytes) peer=1389928
2026-04-20T17:57:27.24Z [msghand] [net] received: block (1606307 bytes) peer=1389928
2026-04-20T17:57:27.30Z [msghand] [net] received block 000000000000000000009143bbce4fcf339db8f66a9d742989db608d3d24e40c peer=1389928
2026-04-20T17:57:27.69Z [msghand] [net] received: block (1606311 bytes) peer=1389928
2026-04-20T17:57:27.76Z [msghand] [net] received block 00000000000000000001d8438112e755297f50dff74b262a6da94c9d2337d422 peer=1389928
2026-04-20T17:57:27.92Z [msghand] [net] received: headers (82 bytes) peer=1389928
2026-04-20T17:57:27.92Z [msghand] [net] received: block (1606307 bytes) peer=1389928
2026-04-20T17:57:28.01Z [msghand] [net] received block 000000000000000000009143bbce4fcf339db8f66a9d742989db608d3d24e40c peer=1389928
2026-04-20T17:57:28.60Z [msghand] [net] received: block (1606311 bytes) peer=1389928
2026-04-20T17:57:28.66Z [msghand] [net] received block 00000000000000000001d8438112e755297f50dff74b262a6da94c9d2337d422 peer=1389928
2026-04-20T17:57:28.71Z [msghand] [net] received: headers (82 bytes) peer=1389928
2026-04-20T17:57:32.81Z [msghand] [net] received: block (1606307 bytes) peer=1389928
2026-04-20T17:57:32.87Z [msghand] [net] received block 000000000000000000009143bbce4fcf339db8f66a9d742989db608d3d24e40c peer=1389928
2026-04-20T17:57:33.72Z [msghand] [net] received: headers (82 bytes) peer=1389928
While 000000000000000000009143bbce4fcf339db8f66a9d742989db608d3d24e40c is the main-chain block 945952 mined by ViaBTC, block 00000000000000000001d8438112e755297f50dff74b262a6da94c9d2337d422 is a stale block at the same height mined by ViaBTC too.
The interesting part here is that they sent the winning block first at 17:57:27.30, then the loosing block at 17:57:27.76 (+460ms), then the winning block again at 17:57:28.01 (+250ms), then the loosing block at 17:57:28.01 (+650ms) and finally the winning block again at 17:57:28.66 (+4310ms).
This peer connected to us with /Satoshi:0.19.0.1/, blocks=0, txrelay=0 (they don’t want to hear about transactions from us), version=70015 from an AWS IP. We’ve seen these before and know they ViaBTC’s bitpeer clients. These announce the ViaBTC blocks to the network and give new blocks they learn about to the mining pool.
We ran into them in Bitcoin Core :: CVE-2024-52922 - Hindered block propagation due to stalling peers and Vulnerability Disclosure: Wasting ViaBTC's 60 EH/s hashrate by sending a P2P message before.
Sudocarlos ·