Testnet3 chain stops syncing at block 4032

[swansontec]

It appears that block 4033 contains something libbitcoin disagrees with, so the sync simply stops:

Storing block 00000000db623a1752143f2f805c4527573570d9b4ca0a3cfe371e703ac429aa: Proof of work does not match bits field

[evoskuil]

The issue most likely arises from chain::validate_block::work_required() in libbitcoin-blockchain.

[veox]

I have built an hour ago (Ubuntu 14.04.2, commit f2bf117), and do not experience this.

P.S. Built using the install.sh script, adding --enable-testnet to the appropriate BUILD*OPTIONS.

[veox]

So, is this reproducible?..

[evoskuil]

I haven't tried it yet.

[evoskuil]

I can't repro using the --without-consensus blockchain option (which would now be required to repro the same scenario). Ubuntu install.sh with --enable-testnet --enable-ndebug --with-consensus.

[evoskuil]

Is this issue resolved? I was never able to reproduce it.

[veox]

IMO OK to close. Couldn't reproduce either. Have re-synced ~4 times since then (most recent ~week ago).

[evoskuil]

Great, thanks! With or without libbitcoin-consensus?

[veox]

With libbitcoin-consensus (using defaults, satoshi's consensus).

[swansontec]

I built a new tesnet server from scratch using the latest release and --disable-consensus --enable-testnet. It was able to sync the entire chain without trouble. I don't know what went wrong with that first one, but it's fixed now.

[evoskuil]

For the sake of clarity, the switch to not use libbitcoin-consensus is --without-consensus, so that would have been a test using the consensus lib.

[thecodefactory]

I'd like to test this in both configurations (with and without consensus), and I'll report back with the results. I know it's already closed ... and I hope it stays that way.

[swansontec]

Oh, sorry. It was --without-consensus. I typed the bug report from memory, but the config script shows that I used the right one.

[thecodefactory]

I can also confirm testnet syncs to current with a fresh build of testnet with consensus.

[evoskuil]

Well it looks like we don't have the Core Testnet bug :).

[thecodefactory]

Yes, it's good news! I have a sync going now on a separate build w/o consensus also. Will report back when it completes (perhaps tomorrow).

[thecodefactory]

And for completeness, a fresh testnet build without consensus also syncs entirely.

[veox]

I've gotten this again. Restarting the server fails on the same block. Rebuilding (install.sh --enable-testnet --prefix=..., default consensus, system's boost) results in failure on a different block, but always early in the sync process (around block 4000 or so).

Possibly related to libbitcoin/libbitcoin-blockchain#85