encrypted wallet backup to SDdisk

[Jet Cash]

I've started experimenting with wallet security. The first thing I did was to backup the blockchain, wallet and associated files by copying them onto an SDcard.  I then backed up the unencrypted wallet directly to a sub-directory on the SDcard, and this worked perfectly. Then I encrypted the wallet, and this seems to have been successful. The next stage was to backup the encrypted wallet directly to the SDcard, and this failed. There is quite a long message, but it seems to have been caused by a CRC error which caused a fatal exception inthe core, and it shut down. I restarted, and backed up the wallet onto the hard disk, and then copied the file onto the SDcard without problem. Does anyone have any idea why backing up directly to an SDcard would cause a problem when the wallet is encrypted?

Details -

HP core i5 computer with lots of space on the hard drive. OS is Windows 10 ( ! ) Bitcoin core 0.11.2 is working well with no other problems.
SDcard is a 128Gb SanDisk Extreme (class 10 ) with an 80 Mb/s rated transfer. No problems with any other use of this card.

[cr1776]

Do you have the exact error?  I presume you are talking about using Bitcoin Core's backup wallet functionality to backup directly to the SD card?

[Jet Cash]

Thanks for the reply, and your presumption is correct. The error message is a bit verbose, but here it is.

A fatal error occurred Bitcoin can no longer continue safely and will quit.

EXCEPTION: N5boost10filesystem16filesystem_errorE
boost::filesystem::status: Data error (cyclic redundancy check): "G:\Backup\enwallet1801.dat"
C:\Program Files\Bitcoin\bitcoin-qt.exe in Runaway exception

G: is obviously the SD card and the directory and file names are correct.

[Jet Cash]

Obviously it is not a hardship to backup to disk, and then make a file copy. I'm trying to understand the fault in case there is something in Windows 10 that is causing the problem. I don't trust Microsoft, and hope that they aren't still keylogging and copying my data.

[sase007]

I've started experimenting with wallet security. The first thing I did was to backup the blockchain, wallet and associated files by copying them onto an SDcard.  I then backed up the unencrypted wallet directly to a sub-directory on the SDcard, and this worked perfectly. Then I encrypted the wallet, and this seems to have been successful. The next stage was to backup the encrypted wallet directly to the SDcard, and this failed. There is quite a long message, but it seems to have been caused by a CRC error which caused a fatal exception inthe core, and it shut down. I restarted, and backed up the wallet onto the hard disk, and then copied the file onto the SDcard without problem. Does anyone have any idea why backing up directly to an SDcard would cause a problem when the wallet is encrypted?

Details -

HP core i5 computer with lots of space on the hard drive. OS is Windows 10 ( ! ) Bitcoin core 0.11.2 is working well with no other problems.
SDcard is a 128Gb SanDisk Extreme (class 10 ) with an 80 Mb/s rated transfer. No problems with any other use of this card.

Simple: flash technology is majorly uncabable at taking this type of demand. You have to consider, when backing up the blockchain ever file is less than 1 mb in size, and he folder is more than 50GB in size.

If you did want to do this, I would suggest you use something like 7 zip to change the files into a Zip, then put it onto the SD card, also making it more efficient.

This is how I understand it anyway.

[Jet Cash]

Sorry I should have been a bit clearer in my description. Core uses the blockchain stored on the hard disk. I backed it up by using a simple file copy, and that worked perfectly. I did think of trying to run a node on my chromebook using and SDcard for the storage, but I gave it up. One of the reasons was the point you made. I made the backup of the blockchain because it took me over two weeks to download it using public wifi.

I could do a direct backup of the unencrypted wallet, bu nowt get the error every time I try to backup since I have encrypted the wallet.

[shorena]

Sorry I should have been a bit clearer in my description. Core uses the blockchain stored on the hard disk. I backed it up by using a simple file copy, and that worked perfectly. I did think of trying to run a node on my chromebook using and SDcard for the storage, but I gave it up. One of the reasons was the point you made. I made the backup of the blockchain because it took me over two weeks to download it using public wifi.

I could do a direct backup of the unencrypted wallet, bu nowt get the error every time I try to backup since I have encrypted the wallet.

Its pretty obvious that sase007 never looked into a folder that stores the blockchain. Im too lazy right now to show how few files actually are below 1MB though.

Anyway, back to topic: Can you show the debug.log at the times you tried to backup to the SDcard? It might give more clues to the source of the error.

[cr1776]

Sorry I should have been a bit clearer in my description. Core uses the blockchain stored on the hard disk. I backed it up by using a simple file copy, and that worked perfectly. I did think of trying to run a node on my chromebook using and SDcard for the storage, but I gave it up. One of the reasons was the point you made. I made the backup of the blockchain because it took me over two weeks to download it using public wifi.

I could do a direct backup of the unencrypted wallet, bu nowt get the error every time I try to backup since I have encrypted the wallet.

You were quite clear.

It could be an error on the SD card.  Do you have a second one to try it with?

[sase007]

Sorry I should have been a bit clearer in my description. Core uses the blockchain stored on the hard disk. I backed it up by using a simple file copy, and that worked perfectly. I did think of trying to run a node on my chromebook using and SDcard for the storage, but I gave it up. One of the reasons was the point you made. I made the backup of the blockchain because it took me over two weeks to download it using public wifi.

I could do a direct backup of the unencrypted wallet, bu nowt get the error every time I try to backup since I have encrypted the wallet.

You were quite clear.

It could be an error on the SD card.  Do you have a second one to try it with?

If he compresses it first, It should work then.
The magnitude of files needed for the SD card is too much for it to handle, however, one file will copy over fine.
As SanDisk are one of the two largest flash makers (the other bing Kingston), it shouldn't be the disk itself, just flash technology in genreal.
It may also depend on the type of drive: SDHC, SDHD, SDXC... ETC, this may have an effect, or whether his drive's port actually has the power to power the drive enougth to power it.

[cr1776]

Sorry I should have been a bit clearer in my description. Core uses the blockchain stored on the hard disk. I backed it up by using a simple file copy, and that worked perfectly. I did think of trying to run a node on my chromebook using and SDcard for the storage, but I gave it up. One of the reasons was the point you made. I made the backup of the blockchain because it took me over two weeks to download it using public wifi.

I could do a direct backup of the unencrypted wallet, bu nowt get the error every time I try to backup since I have encrypted the wallet.

You were quite clear.

It could be an error on the SD card.  Do you have a second one to try it with?

If he compresses it first, It should work then.
The magnitude of files needed for the SD card is too much for it to handle, however, one file will copy over fine.
As SanDisk are one of the two largest flash makers (the other bing Kingston), it shouldn't be the disk itself, just flash technology in genreal.
It may also depend on the type of drive: SDHC, SDHD, SDXC... ETC, this may have an effect, or whether his drive's port actually has the power to power the drive enougth to power it.

He is only talking about storing the wallet on the SD card as he has said several times.   Consequently, the "magnitude of the files needed" to store the wallet there is not an issue.  The wallet.dat file is almost always quite small.


Many of the people with sig campaigns are just posting to get their post count up, so their advice is best taken with a grain of salt.

[Jet Cash]

Good morning guys, I've now got myself a black coffee, and I'll sit here and do a bit more experimenting. Debug file to come later when I've worked out where it is.

The blockchain is not a problem. The directory contains (wait for it ) a chain of blocks, and each one is a discrete file of around 130Kb. I think there are over 400 of them, and there is no problem copying them. I'm going to try direct back-ups to an USB stick, and another SD card ( a cheaper one that is in the camera). Obviously I can only work with the encrypted wallet now. I'm in McD at 5am, and they have just started breakfasts, so give me time to get another coffee, and an egg wrap.

[achow101]

Good morning guys, I've now got myself a black coffee, and I'll sit here and do a bit more experimenting. Debug file to come later when I've worked out where it is.

The debug.log file is located in %appdata%/bitcoin if you did not change the datadir.

From your error message, I would guess that there is a problem with boost and its file writing capabilities. Maybe the SD card has read/write problems which boost can't handle but windows can?

[Jet Cash]

Thanks. I looked at the log file, and there is some extra stuff in there, so I thought I would wait until I could replicate the problem before posting it. I'm just catching up with the blockchain atm. I was 11 hours behind, and I'm on public WiFi running at around 30Kb/s, so it will be a few more minutes.

Thanks for the comment about boost, and I hope that is the problem. I was concerned that it might be something that Windows 10 was doing. I can live with a Bitcoin limitation, as I said, it's easy to back up my wallet using a two stage process.

I guess I need to read up on boost. I assume it is a file handling routine.

[Jet Cash]

Update -

Tried saving to a USB stick, and that worked without any problems
Tried saving to a micro-SD card via an adapter, and core said that I couldn't save it there.
Went back to the original SD card, and tried saving to that. Core now tells me that I can't save it there either.

I guess that I should just accept life, and use USB sticks for Bitcoin backups. I don't think it is worth pursuing the original error any further, although it would be nice to know why it tried to use the card yesterday and failed, and today it just says "tough, you can't do this". I guess Bitcoin is better than me, at least it learns by its mistakes.

[cr1776]

...
If he compresses it first, It should work then.
The magnitude of files needed for the SD card is too much for it to handle, however, one file will copy over fine.
As SanDisk are one of the two largest flash makers (the other bing Kingston), it shouldn't be the disk itself, just flash technology in genreal.
It may also depend on the type of drive: SDHC, SDHD, SDXC... ETC, this may have an effect, or whether his drive's port actually has the power to power the drive enougth to power it.

Title:  "encrypted wallet backup to SDdisk"
1st sentence: " experimenting with wallet security"
Next: "I then backed up the unencrypted wallet directly to a sub-directory on the SDcard"
Next: "Then I encrypted the wallet"
Next: "...backup the encrypted wallet directly to the SDcard, and this failed."

Clearly he is talking about backing up the wallet, not the entire directory.

Perhaps not a sig campaigner, if not, apologies.

[Jet Cash]

I guess I'd still be interested in finding out why boost doesn't like SD disks, but I guess that's a topic for another thread. I'd assumed that an SD disk was the equivalent of a hard disk, but a bit slower.

btw - did you guys know that a hard drive is known as a Winchester disk because it was developed just outside Winchester in Hampshire, England.

[deepceleron]

btw - did you guys know that a hard drive is known as a Winchester disk because it was developed just outside Winchester in Hampshire, England.

Hard drives were developed by IBM in San Jose, the first being the RAMAC 350 in 1956.

The "Winchester" name came in 1973 from the IBM 3340 project head Kenneth E. Haughton. This drive, which was to have two 30MB disk banks (30-30), got the nickname from the Winchester 30-30 rifle.

Just to note - you must destroy a SD card that had any unencrypted wallet data on it. There is no method to securely erase data off them (although filling them with raw 00s and FFs multiple times might deter the casual discovery).

[Jet Cash]

Sorry - The first winchester was 5Mb, and it was about the size of a house brick. The research and development was done in IBM's Hursley labs just outside Winchester. I used 3340s back in the days when I was a mainframe programmer, and nobody called them Winchesters. I read the Wikipedia article, and they seemed to think that Seagate made the first drives for the PC. I believe that IBM made the drives they put into the XT. I also worked with a removable drum storage device on an ICT 1900. That was one of the worst drives ever. It wrapped a flexible medium around a fixed drum, and didn't last very long.

My first programming was done on an IBM 421 which used a plug board, and then on an IBM 1401 using punched cards.

Is anyone here older than me?

[Jet Cash]

Here is another tit-bit for you. Microsoft didn't write the original PC/MS-DOS. They purchased it from Xerox, just after Lord Rank bought the company for its Xerography process, and refused to sell the products, but only allowed them to be rented with a pay-per-copy contract. Of course M/s went on to develop the OS.

[deepceleron]

Here is another tit-bit for you. Microsoft didn't write the original PC/MS-DOS. They purchased it from Xerox, just after Lord Rank bought the company for its Xerography process, and refused to sell the products, but only allowed them to be rented with a pay-per-copy contract. Of course M/s went on to develop the OS.

Also wrong. Microsoft licensed the code and then purchased full rights for Tim Patterson's Seattle Computer Products 86-DOS for $50,000.  https://en.wikipedia.org/wiki/86-DOS