Alert: chain fork caused by pre-0.8 clients dealing badly with large blocks

[etotheipi]

The original post lacked info for "regular users".  Here it is:

(1) If you are a "regular user" (not a miner), the best thing is to do nothing and wait a couple hours.
(2) If you are a "regular user", upgrading, downgrading, whining, FUD, etc, will make no difference.  Only miners have an incentive to do anything.  Otherwise, it doesn't matter which version you are running.
(3) Regardless of who you are, your transactions are not dead, your coins are not lost.  They will just temporarily be held up.  If you sent a transaction within the last few hours, it may take a few more hours before it's sorted out.
(4) If you insist on processing transactions right now it's probably best to wait 30+ confirmations.  It's just due diligence though ... an attacker would still need a tremendous amount of mining power, quick thinking, and a victim willing to part with a lot of BTC.
(5) By tomorrow this will be in the past and everything will appear to be normal again.  If you slept through this, you'd never know that anything happend (except for the price drop).

Let me reiterate, your coins are not at risk, your transactions are not lost.  It'll just take some time for the network to "iron itself out."  Everything will be okay.

[whitenight639]

Also can I buy bitcoins on localbitcoins and take advantage of this crazyness without loosing my money??

[Maged]

will downgrading redownload the entire chain? because wasnt the old db converted?

Nope, because the developers thought ahead with that point. Your chain will start at the last point you ran a 0.7 or below client.

[glitch003]

This sucks but at least we're working out all these bugs right now (how to handle version upgrades safely, etc) while Bitcoin is still in it's infancy.  Better that this happen now than in the future when more people are utilizing the network and the consequences could be worse.

This is all part of the risk that we incur, and is exactly the reason why everyone says "don't invest more in Bitcoin than you can spare to lose"

[dree12]

So let me get this right,

IF we'd all upgrade to .08 then the blocksize restriction would have been lifted, but because not many did we now have a fork and because the 0.7 blockchain is longer we should revert to that until a proper upgrade path to 0.8 is made available?

so is 0.8 inherently flawed, I thought there was a consensus that the blocksize should be lifted? I think this is very poor

 A simple retards guide summing up key points for and against blocksize restriction or lifting should have been stickied in the forum for some time and a poll taken by everybody not just miners, devs and long time posters.

An upgrade should have been built and tested on an isolated blockchain if that is possible,

A announcement about the upcoming availability of the upgrade should have been stickied referring to the poll results and post aforementioned,

A target date and block number should have been specified and downloads of the new client should have been made available along with an "alert£"

Some time before the specified date / block another last chance alert should hav been issued, anyone not upgrading after the date / block should have been left in the dust.

0.8 did not lift the blocksize. The block being big is just a specific problem, it could have been a block too small or too strange (the problem was, however, that the block was very big—but not "too big"). The problem was 0.7 and below rejecting a block that should have been accepted.

0.8 is not flawed. The flaw lied in 0.7 and below. If an upgrade was hastened, the problem would not have been a problem at all.

[superfastkyle]

mt gox had disabled btc withdrawals
we will see below $30 before the night is over

[bitpop]

Thanks, reverted to .7. Seeing a lot of errors and going to just let it run.
I'm going to consider myself a miner because I run a p2pool node though I don't think anyone is using it at this point.

will downgrading redownload the entire chain? because wasnt the old db converted?

Nope, because the developers thought ahead with that point. Your chain will start at the last point you ran a 0.7 or below client.

[ehoffman]

I do have transaction that are stucked.  Probable cause is that the server I sent to is with the old code, and don't see my transaction.  My client (0.8 ) does see transaction as confirmed.

[bit365]

The original post lacked info for "regular users".  Here it is:

(1) If you are a "regular user" (not a miner), the best thing is to do nothing and wait a couple hours.
(2) If you are a "regular user",  Upgrading, downgrading, whining, FUD, etc, will make no difference.  Only miners have an incentive to do anything.
(3) Regardless of who you are, your transactions are not dead, your coins are not lost.  They will just temporarily be held up.  If you sent a transaction within the last few hours, it may take a few more hours before it's sorted out.
(4) If you insist on processing transactions right now it's probably best to wait 30+ confirmations.  It's just due diligence though ... an attacker would still need a tremendous amount of mining power, quick thinking, and a victim willing to part with a lot of BTC.
(5) By tomorrow this will be in the past and everything will appear to be normal again.  If you slept through this, you'd never know that anything happend (except for the price drop).

Let me reiterate, your coins are not at risk, your transactions are not lost.  It'll just take some time for the network to "iron itself out."  Everything will be okay.

Very good info.

[Luke-Jr]

Any idea what version eligius is on?

0.6.0

Deepbit is 0.3.21 IIRC

[No_2]

So let me get this right,

IF we'd all upgrade to .08 then the blocksize restriction would have been lifted, but because not many did we now have a fork and because the 0.7 blockchain is longer we should revert to that until a proper upgrade path to 0.8 is made available?

so is 0.8 inherently flawed, I thought there was a consensus that the blocksize should be lifted? I think this is very poor

 A simple retards guide summing up key points for and against blocksize restriction or lifting should have been stickied in the forum for some time and a poll taken by everybody not just miners, devs and long time posters.

An upgrade should have been built and tested on an isolated blockchain if that is possible,

A announcement about the upcoming availability of the upgrade should have been stickied referring to the poll results and post aforementioned,

A target date and block number should have been specified and downloads of the new client should have been made available along with an "alert£"

Some time before the specified date / block another last chance alert should hav been issued, anyone not upgrading after the date / block should have been left in the dust.

I agree. Did anyone test this? Empirical evidence and testing edge cases are crucial.

[NilamDoc]

The problem is not with the wallet, the problem is with the client 0.7 which was mining. It was not able to accept block chain height 225430.

So,
- if you are using 0.8 -- do not worry
- if you are using 0.8 and mining - stop mining and wait till proper instruction comes from the core development team.
- if you are using 0.7 and not mining - do not worry
- if you are using 0.7 and mining - stop mining and wait till proper instruction comes from the core development team.

blockchain.info has the same alert message and also mtgox.com has stopped accepting inputs

Wait till we get another alert from core team!

[ChanceCoats123]

Any idea what version eligius is on?

0.6.0

Deepbit is 0.3.21 IIRC

Thank you for the update!

[whitenight639]

So let me get this right,

IF we'd all upgrade to .08 then the blocksize restriction would have been lifted, but because not many did we now have a fork and because the 0.7 blockchain is longer we should revert to that until a proper upgrade path to 0.8 is made available?

so is 0.8 inherently flawed, I thought there was a consensus that the blocksize should be lifted? I think this is very poor

 A simple retards guide summing up key points for and against blocksize restriction or lifting should have been stickied in the forum for some time and a poll taken by everybody not just miners, devs and long time posters.

An upgrade should have been built and tested on an isolated blockchain if that is possible,

A announcement about the upcoming availability of the upgrade should have been stickied referring to the poll results and post aforementioned,

A target date and block number should have been specified and downloads of the new client should have been made available along with an "alert£"

Some time before the specified date / block another last chance alert should hav been issued, anyone not upgrading after the date / block should have been left in the dust.

0.8 did not lift the blocksize. The block being big is just a specific problem, it could have been a block too small or too strange (the problem was, however, that the block was very big—but not "too big"). The problem was 0.7 and below rejecting a block that should have been accepted.

0.8 is not flawed. The flaw lied in 0.7 and below. If an upgrade was hastened, the problem would not have been a problem at all.

So why are we being told to downgrade if there is an issue with 0.7 accepting / producing (the rare) malformed block, has this issue been addressed in 0.8?

If this is like a zero day issue then everyone rushing to back to the 0.7 that still has the issue is strange, especially if the 0.8 client can integrate the blocks / blockchain produced from 0.7 clients.


It's like finding a vulnarability in XP and then asking Vista users to downgrade to it.  

[gmaxwell]

0.8 is not flawed. The flaw lied in 0.7 and below. If an upgrade was hastened, the problem would not have been a problem at all.

Sadly, 0.8 is flawed— its "one job" was to faithfully follow the behavior of 0.7, "bugs" and all. It did not. Had we known about this behavior in 0.7 or had testing turned it up we would have made sure 0.8 behaved the same way.

This is the nature of a distributed consensus system.  The primary definition of right and wrong is "consistent" and if you aren't consistent you aren't right, no matter what.

[-ck]

Let no one say that pooled mining is bad for bitcoin now, given how quickly the pool operators corrected this potential disaster and coordinated its recovery... It would have taken a lot longer for thousands of solo miners to have corrected it.

[singpolyma]

Is there a plan to safely upgrade the network so that blocks like this can be accepted in the future?  Or is it undesirable to have accepted this block?

[dree12]

0.8 is not flawed. The flaw lied in 0.7 and below. If an upgrade was hastened, the problem would not have been a problem at all.

Sadly, 0.8 is flawed— its "one job" was to faithfully follow the behavior of 0.7, "bugs" and all. It did not. Had we known about this behavior in 0.7 or had testing turned it up we would have made sure 0.8 behaved the same way.

This is the nature of a distributed consensus system.  The primary definition of right and wrong is "consistent" and if you aren't consistent you aren't right, no matter what.

The testing should have happened with the older version of Bitcoin. I don't see how testing 0.8 would fix this issue, given that 0.8 fixes the bug.

[BookLover]

The original post lacked info for "regular users".  Here it is:

(1) If you are a "regular user" (not a miner), the best thing is to do nothing and wait a couple hours.
(2) If you are a "regular user",  Upgrading, downgrading, whining, FUD, etc, will make no difference.  Only miners have an incentive to do anything.
(3) Regardless of who you are, your transactions are not dead, your coins are not lost.  They will just temporarily be held up.  If you sent a transaction within the last few hours, it may take a few more hours before it's sorted out.
(4) If you insist on processing transactions right now it's probably best to wait 30+ confirmations.  It's just due diligence though ... an attacker would still need a tremendous amount of mining power, quick thinking, and a victim willing to part with a lot of BTC.
(5) By tomorrow this will be in the past and everything will appear to be normal again.  If you slept through this, you'd never know that anything happend (except for the price drop).

Let me reiterate, your coins are not at risk, your transactions are not lost.  It'll just take some time for the network to "iron itself out."  Everything will be okay.

Very good info.

+1

The testing should have happened with the older version of Bitcoin. I don't see how testing 0.8 would fix this issue, given that 0.8 fixes the bug.

It depends on your point of view to which client has the "bug".  The problem was an inconsistency with the clients, so you could say since 0.7 was already out 0.8 was the inconsistent client.

[singpolyma]

Let no one say that pooled mining is bad for bitcoin now, given how quickly the pool operators corrected this potential disaster and coordinated its recovery... It would have taken a lot longer for thousands of solo miners to have corrected it.

If mining were less centralized, the 0.8 chain would have become the default, and the instructions would instead be "everyone upgrade now".