ERROR: Incorrect Total Difficulty

[simenfd]

I get a lot of "ERROR: Incorrect Total Difficulty" after recompiling the latest version on linux
(commit: 1fa844a). Every block received creates this message... I believe this might disappear if I delete .ethereum/

I submit this FYI.

I0413 19:29:59.693187 13361 backend.go:183] Protocol Version: 60, Network Id: 0
I0413 19:29:59.693248 13361 backend.go:193] Blockchain DB Version: 1
I0413 19:29:59.694546 13361 chain_manager.go:186] Last block (#90176) 9a346f8ccb15f83de4f297c1709f8e15e98154a696bfd994047d3a892ea44a99 TD=239597588340
I0413 19:30:00.573348 13361 ethash.go:94] Making cache
I0413 19:30:01.841700 13361 ethash.go:99] Took: 1.268275564s
I0413 19:30:01.849193 13361 cmd.go:116] Starting Geth/v0.9.9/linux/go1.4.2
I0413 19:30:01.849303 13361 server.go:170] Starting Server
I0413 19:30:01.852512 13361 udp.go:157] Listening, enode://0422c0381b41f85b84ecbfaacb832c7c00f2c80a07b8b444867b64b1ae8b720f14584ae688b7a475528d0f5e0758718bedc0ed24e0897893103c050ee5f39e77@84.209.71.211:30303
I0413 19:30:01.852603 13361 blockpool.go:276] Blockpool started
I0413 19:30:01.852618 13361 whisper.go:75] Whisper started
I0413 19:30:01.852638 13361 backend.go:396] Server started
I0413 19:30:01.852687 13361 server.go:286] Listening on [::]:30303
I0413 19:30:10.614995 13361 errors.go:82] [ETH] ERROR: NetworkId mismatch: 99107 (!= 0)
I0413 19:30:13.409319 13361 chain_manager.go:548] imported 4 block(s) 0 queued in 25.649576ms. #90180 [e9138445 / 3f39480a]
I0413 19:30:13.409456 13361 errors.go:82] [Blockpool] ERROR: Incorrect Total Difficulty: on block 3f39480a75a07af4e3169b0ed396e72eae7fddf5e770119b61e7cecadc79c311 peer td 249199161275 =?= block td 239624647985

[obscuren]

It's fine. You may safely ignore it :-)

[zelig]

People were asking so here you go.a few nodes on the test net advertise incorrect high total difficulty for their head block. We never follow them as best peers otherwise we risk lagging behind if they are slow or even get stuck on a bad fork if they decide to start mining on their high td block. 

If the offending node is malicious this can be called a chain hijacking attack which has a lucrative potential if 51 percent runs the naive client. 

So it is quite important to detect incorrectly advertised td and deal with offending peers. 

For now we don't kick them out cos we know its some well meaning client with a problem and also given our small network we opportunistically harness them to provide their valid blocks. 
These pre frontier days of lenience are soon over though.

That said they should be suspended (prevent them from gaining best peer status for a set period of suspension or the duration of the connection (whichever is longer).

See also #604

-------- Original message --------
From: simenfd notifications@github.com
Date:13/04/2015 18:38 (GMT+00:00)
To: ethereum/go-ethereum go-ethereum@noreply.github.com
Cc:
Subject: [go-ethereum] ERROR: Incorrect Total Difficulty (#706)

I get a lot of "ERROR: Incorrect Total Difficulty" after recompiling the latest version on linux
(commit: 1fa844a). Every block received creates this message... I believe this might disappear if I delete .ethereum/

I submit this FYI.

I0413 19:29:59.693187 13361 backend.go:183] Protocol Version: 60, Network Id: 0
I0413 19:29:59.693248 13361 backend.go:193] Blockchain DB Version: 1
I0413 19:29:59.694546 13361 chain_manager.go:186] Last block (#90176) 9a346f8ccb15f83de4f297c1709f8e15e98154a696bfd994047d3a892ea44a99 TD=239597588340
I0413 19:30:00.573348 13361 ethash.go:94] Making cache
I0413 19:30:01.841700 13361 ethash.go:99] Took: 1.268275564s
I0413 19:30:01.849193 13361 cmd.go:116] Starting Geth/v0.9.9/linux/go1.4.2
I0413 19:30:01.849303 13361 server.go:170] Starting Server
I0413 19:30:01.852512 13361 udp.go:157] Listening, enode://0422c0381b41f85b84ecbfaacb832c7c00f2c80a07b8b444867b64b1ae8b720f14584ae688b7a475528d0f5e0758718bedc0ed24e0897893103c050ee5f39e77@84.209.71.211:30303
I0413 19:30:01.852603 13361 blockpool.go:276] Blockpool started
I0413 19:30:01.852618 13361 whisper.go:75] Whisper started
I0413 19:30:01.852638 13361 backend.go:396] Server started
I0413 19:30:01.852687 13361 server.go:286] Listening on [::]:30303
I0413 19:30:10.614995 13361 errors.go:82] [ETH] ERROR: NetworkId mismatch: 99107 (!= 0)
I0413 19:30:13.409319 13361 chain_manager.go:548] imported 4 block(s) 0 queued in 25.649576ms. #90180 [e9138445 / 3f39480a]
I0413 19:30:13.409456 13361 errors.go:82] [Blockpool] ERROR: Incorrect Total Difficulty: on block 3f39480a75a07af4e3169b0ed396e72eae7fddf5e770119b61e7cecadc79c311 peer td 249199161275 =?= block td 239624647985

—
Reply to this email directly or view it on GitHub.