connections with v2 transport
Bitcoin Core v26.0 (released November 2023) introduced experimental support for BIP324 v2 transport, but it was off by default and had to be enabled manually using the -v2transport option. It was enabled by default in Bitcoin Core v27.0, which was released in April 2024. In June 2026, more than 80% of the outbound connection attempts my nodes make are to v2 nodes.
It can happen, that we try to make a v2 connection to a node which does not support v2 transport. For example, when we store an address with the service flag `NODE_P2P_V2` set in our address manager, because we received it this way through address gossip. We’ll attempt a v2 connection, but downgrade to v1 if we can connect, but can not establish a v2 connection.
My nodes downgrade from v2 → v1 transport for about 30 to 40 connections per day. Depending on node, they have between 200 and 400 successful connection attempts per day. This means, we have a v2 → downgrade rate somewhere between 15% and 20%. Most of these seem to be feeler connections. This is expected, as we’re using information from the new table for feelers. In the tried table, we’ve updated potential service flag mismatches after a first connection.
