server: Respond to getheaders when same chain tip. #2587
Merged
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The handler for
getheaders
currently ignores the request when the chain is not yet believed to be current. This is generally desirable and correct behavior, since it might otherwise lead peers to incorrect conclusions about the state of the peer.However, on private networks, such as simnet, it is not at all uncommon for every node in the network to no longer be current if a block hasn't been mined in a long time or when all nodes are stopped and restarted.
In order to better handle these types of edge conditions, this modifies the server to respond to
getheaders
when the local chain tip is exactly the same as the requested locator even when it is not marked current yet.This results in more robust handling for private networks while still providing the normal desirable behavior prior to being current.