Change Details

The seeder currently only bans misbehaving nodes. With D5380, this change will allow the seeder to eventually ban a node on the wrong chain. The previous issue noted in D5380 was that the seeder could not differentiate between an IBD node and a node on the wrong chain. An IBD node should not be banned while the other type should be banned. Given enough time, a good node should finish its IBD and pass TestNode(). On the other hand, a node on the wrong chain very likely won't change become good later on. Depends on D5380 and D5800 Review note: The seeder is currently unable to reach the unbanning logic while it is running. In order for a node to be unbanned, the seeder must be restarted with the `--wipeban` option enabled. As such banned nodes are effectively banned forever.

The seeder currently only bans misbehaving nodes. With D5380, this change will allow the seeder to eventually ban a node on the wrong chain. As previously noted in D5380, the seeder cannot differentiate between an IBD node/a node stuck behind the checkpoint a node on the wrong chain. Only a node clearly on the wrong chain should be banned. Given enough time, a good node should finish its IBD and pass CSeederNode.Run(). On the other hand, a node on the wrong chain very likely won't change become good later on. Nodes worthy of being banned must have the following properties: (1) Have failed the current run of CSeederNode.Run() (2) Be following the wrong chain (3) Have poor reliability (4) Have not recently (within the last two days) passed CSeederNode.Run() (1) and (2) are determined by the communications from `CSeederNode.Run()`. (3) is determined by `IsReliable()`, the results of repeated iteration of a reliability function. This prevents banning nodes that may only be following part of the chain, but are at least useful as seeds for part of the chain. Core nodes with high reliability, for example, are not following the correct chain, but are still useful for IBD of a fresh node. Excluding the edge case of previously untested node, (4) is determined using `ourLastSuccess`. In order to solve the edge case, the seeder's database must additionally track the time a node was first discovered otherwise all fresh nodes would be banned on their first `CSeederNode.Run()` failure. Depends on D5380 and D5800 Review note: The seeder is currently unable to reach the unbanning logic while it is running. In order for a node to be unbanned, the seeder must be restarted with the `--wipeban` option enabled. As such banned nodes are effectively banned forever.

The seeder currently only bans misbehaving nodes. With D5380, this change will allow the seeder to eventually ban a node on the wrong chain. TheAs previous issuesly noted in D5380 was that, the seeder could notannot differentiate between differentiate between an IBD node andan IBD node/a node stuck behind the checkpoint a node on the wrong chain. An IBD node should not be banned whileOnly a node clearly on the other typewrong chain should be banned. Given enough time, a good node should finish its IBD and pass TestCSeederNode.Run(). On the other hand, a node on the wrong chain very likely won't change become good later on. Nodes worthy of being banned must have the following properties: (1) Have failed the current run of CSeederNode.Run() (2) Be following the wrong chain (3) Have poor reliability (4) Have not recently (within the last two days) passed CSeederNode.Run() (1) and (2) are determined by the communications from `CSeederNode.Run()`. (3) is determined by `IsReliable()`, the results of repeated iteration of a reliability function. This prevents banning nodes that may only be following part of the chain, but are at least useful as seeds for part of the chain. Core nodes with high reliability, for example, are not following the correct chain, but are still useful for IBD of a fresh node. Excluding the edge case of previously untested node, (4) is determined using `ourLastSuccess`. In order to solve the edge case, the seeder's database must additionally track the time a node was first discovered otherwise all fresh nodes would be banned on their first `CSeederNode.Run()` failure. Depends on D5380 and D5800 Review note: The seeder is currently unable to reach the unbanning logic while it is running. In order for a node to be unbanned, the seeder must be restarted with the `--wipeban` option enabled. As such banned nodes are effectively banned forever.