Two-factor authorization (trustedcoin) with multiple devices afterwards

[typesoshee]

I've set up a 2fa Electrum wallet, and I had Google Authenticator on my phone recognize the QR code that was shown on screen during the set up so that my Google Authenticator has a trustedcoin.com account that gives me that 6-digit code every 30 seconds or so.  However, I'd like to be able to use my Electrum account in case I lose my phone.  Can I set up the same thing with Google Authenticator on my tablet?  I didn't print out or save an image of the QR code that was given by Electrum during the initial set up.

Thanks!

[jackbox]

I've set up a 2fa Electrum wallet, and I had Google Authenticator on my phone recognize the QR code that was shown on screen during the set up so that my Google Authenticator has a trustedcoin.com account that gives me that 6-digit code every 30 seconds or so.  However, I'd like to be able to use my Electrum account in case I lose my phone.  Can I set up the same thing with Google Authenticator on my tablet?  I didn't print out or save an image of the QR code that was given by Electrum during the initial set up.

Thanks!

Not sure bout that. In the future consider using Authy. It is Google Authenticator compatible and gives you a way to save all your credentials in an encrypted format on their glad. Can use on multiple devices and change phones, etc.

[typesoshee]

Yeah, Authy does feel easier to use.  The choice/process to use it on multiple devices was pretty simple.  But interestingly, perhaps this relative "airtightness" of Google Authenticator makes it more secure, according to this:

http://android.stackexchange.com/a/92915

In any case, I'd like to know if there's any way I can "access" or "get a glimpse" of the QR code of the 2fa that my Electrum wallet is associated with, or some other way to use Google Authenticator/trustedcoin on 2 devices.

[jackbox]

Yeah, Authy does feel easier to use.  The choice/process to use it on multiple devices was pretty simple.  But interestingly, perhaps this relative "airtightness" of Google Authenticator makes it more secure, according to this:

http://android.stackexchange.com/a/92915

In any case, I'd like to know if there's any way I can "access" or "get a glimpse" of the QR code of the 2fa that my Electrum wallet is associated with, or some other way to use Google Authenticator/trustedcoin on 2 devices.

A lot of programs and websites will only display it one time and once you confirm it by entering the proper code they will never show it again for security purposes. Some sites warn you to make a screenshot to preserve it before confirming it and it disappearing.

[btchris]

Yeah, Authy does feel easier to use.  The choice/process to use it on multiple devices was pretty simple.  But interestingly, perhaps this relative "airtightness" of Google Authenticator makes it more secure, according to this:

http://android.stackexchange.com/a/92915

In any case, I'd like to know if there's any way I can "access" or "get a glimpse" of the QR code of the 2fa that my Electrum wallet is associated with, or some other way to use Google Authenticator/trustedcoin on 2 devices.

Agreed that Authy vs Google Authenticator (or FreeOTP if you prefer, which is open source) is a convenience vs security & privacy decision.

I don't think there's any way to replicate your Google Authenticator into another device unless your first device is rooted (and even then, it might be a little tricky unless your second device was also rooted).

[Abdussamad]

Did you note down the 25 word mnemonic when creating the wallet? If in future you lose access to your phone you can recover your wallet using that mnemonic. That's your failsafe. After you recover the wallet using the mnemonic it ceases to be a 2fa wallet.

[typesoshee]

Did you note down the 25 word mnemonic when creating the wallet? If in future you lose access to your phone you can recover your wallet using that mnemonic. That's your failsafe. After you recover the wallet using the mnemonic it ceases to be a 2fa wallet.

So it becomes a regular wallet after recovering?  That makes sense, thanks.

Right now, I'm thinking of just creating a new 2fa wallet, get the new QR code with both my phone and tablet, and then send all my bitcoins in my current 2fa wallet to my new one. 

[typesoshee]

Agreed that Authy vs Google Authenticator (or FreeOTP if you prefer, which is open source) is a convenience vs security & privacy decision.

I don't think there's any way to replicate your Google Authenticator into another device unless your first device is rooted (and even then, it might be a little tricky unless your second device was also rooted).

Both my devices are rooted. I tried this here:

http://android.stackexchange.com/a/86861

but I'm totally unfamiliar with these things, and when I tried the adb pull thing, it just gave me "device not found." 

I haven't tried this answer yet, which is in the same thread:

http://android.stackexchange.com/a/92140

Instead, I might just create a new 2fa wallet, get the QR code with both of my devices, and then send all my bitcoins in my current 2fa wallet to this new 2fa wallet.  I imagine that's easier than messing around with android root stuff that's beyond my head.  Plus, theoretically, copying and pasting the android files that contain my Google Authenticator stuff into my desktop seems like an extra security risk.

[btchris]

Both my devices are rooted. I tried this here:

http://android.stackexchange.com/a/86861

but I'm totally unfamiliar with these things, and when I tried the adb pull thing, it just gave me "device not found." 

I haven't tried this answer yet, which is in the same thread:

http://android.stackexchange.com/a/92140

Instead, I might just create a new 2fa wallet, get the QR code with both of my devices, and then send all my bitcoins in my current 2fa wallet to this new 2fa wallet.  I imagine that's easier than messing around with android root stuff that's beyond my head.  Plus, theoretically, copying and pasting the android files that contain my Google Authenticator stuff into my desktop seems like an extra security risk.

Titanium Backup is the exact method I was going to suggest if they were both rooted, but if you're uncomfortable with it, then your last method above seems best to me. (FYI Titanium Backup offers encryption, but only for the paid "Pro" version.)

Also if they're rooted, you may want to consider SuperSU as your su app, it can PIN-protect root access which may be more secure if you're using it for 2FA or with an Android wallet. Just be sure to read the docs if you ever decide to uninstall SuperSU to avoid losing root.

[typesoshee]

Yup, I ended up just creating a new Electrum 2fa wallet, scan the QR code that Electrum shows me to both of my devices, and then sent all my existing bitcoins in my old 2fa wallet to the newly created one.

It looks like SuperSU offers PIN protection only for its pro version: http://forum.xda-developers.com/showthread.php?t=1538053

[btchris]

It looks like SuperSU offers PIN protection only for its pro version: http://forum.xda-developers.com/showthread.php?t=1538053

Sorry, my bad, I have the pro version and didn't remember it wasn't available without it.