Questions[passphrase](ubuntu)

I followed steps from this guide to try to install Cast to TV. When I executed the step "by restarting Gnome Shell (using Xorg: press Alt + F2, type r, and press Enter" things went bad. I think I turned the laptop off using the power button, then could not turn it back on. When I tried to re-install the same version of Ubuntu from a Live USB without losing my files, the installer said no existing operating system was found.

I used Ubuntu 19.10 on a Dell XPS laptop.

Additionally I tried to recover my files from the encrypted hard drive on my laptop through a Live USB but needed my mount passphrase (to access the encrypted hard drive), which seems to be different from my password, which I enter upon start-up every time.

Following this guide, I tried to recover my passphrase, but both commands ecryptfs-unwrap-passphrase and sudo ecryptfs-recover-private didn't give any reaction.

Any help in recovering my files or recovering my ubuntu version are highly appreciated! Or if anyone knows what I might have done with the command "Alt + F2"; "r"; "Enter", that might help, too.

EDIT: I managed to rescue my files from a Live USB:

1) had to mount my corrupted hard drive using only password, no mount passphrase

2) running sudo nautilus

3) copying all my files to an external hard drive in the sudo nautilus window

Thanks for your interest and your help, community!

James

I have set up a password-less setup for ssh that uses public key authentication to connect with desired remote server, everything has been working quite well.

I'm using passphrase to unlock the private key, using this solution— the problem is it asks password everytime I start my system.

I found this to be troublesome, I want to enter it only once and for all so the next time I boot up the session I won't have to enter it again, is there something like cached key that holds up my passphrase and works across session (also survive a reboot) ?

Would it be possible to achieve all of this whilst keeping my ssh passphrase intact ?

When I installed Ubuntu 19 it offered to encrypt the disc where I have my /home partition. I chose that because I thought my data would be safer.

For different reasons I was not happy with Ubuntu 19, so I installed Ubuntu 18, leaving the /home disc untouched.

Now it is impossible to mount the disc though. I had to make a /home directory on the (smaller) system disc to continue at all. Now mounting the old disc as /home2 I managed to get to this point:

root@host:/home2# ecryptfs-unwrap-passphrase /home2/.ecryptfs/user/.ecryptfs/wrapped-passphrase 
Passphrase: ********
2abd39dc3693535ca43a2bf40691f5b9  

root@host:/home2# sudo ecryptfs-add-passphrase --fnek
Passphrase: 
Inserted auth tok with sig [934485b75a55371a] into the user session keyring 
Inserted auth tok with sig [ec2a4a6c55ccb30f] into the user session keyring

and then proceeded to mount with:

root@host:/home2# sudo mount -t ecryptfs /home2/.ecryptfs/user/.Private /mnt/
Passphrase: 
Select cipher: 
 1) aes: blocksize = 16; min keysize = 16; max keysize = 32
 2) blowfish: blocksize = 8; min keysize = 16; max keysize = 56
 3) des3_ede: blocksize = 8; min keysize = 24; max keysize = 24
 4) twofish: blocksize = 16; min keysize = 16; max keysize = 32
 5) cast6: blocksize = 16; min keysize = 16; max keysize = 32
 6) cast5: blocksize = 8; min keysize = 5; max keysize = 16
Selection [aes]: 
Select key bytes: 
 1) 16
 2) 32
 3) 24
Selection [16]: 
Enable plaintext passthrough (y/n) [n]: n
Enable filename encryption (y/n) [n]: y
Filename Encryption Key (FNEK) Signature [934485b75a55371a]: 
Attempting to mount with the following options:
  ecryptfs_unlink_sigs
  ecryptfs_fnek_sig=934485b75a55371a
  ecryptfs_key_bytes=16
  ecryptfs_cipher=aes
  ecryptfs_sig=934485b75a55371a
Mounted eCryptfs

which looks hopeful. But then when I go into /mnt I get

root@host:/home2# ls /mnt/
ls: cannot access '/mnt/Public': No such file or directory
ls: cannot access '/mnt/Handboek Communicatiestijl.pdf': No such file or directory
ls: cannot access '/mnt/Videos': No such file or directory
ls: cannot access '/mnt/home': No such file or directory
ls: cannot access '/mnt/Music': No such file or directory
ls: cannot access '/mnt/Desktop': No such file or directory
ls: cannot access '/mnt/Templates': No such file or directory
ls: cannot access '/mnt/Documents': No such file or directory
ls: cannot access '/mnt/Downloads': No such file or directory
ls: cannot access '/mnt/Pictures': No such file or directory
ls: cannot access '/mnt/projects': No such file or directory
ls: cannot access '/mnt/work': No such file or directory
ls: cannot access '/mnt/NVIDIA_CUDA-10.1_Samples': No such file or directory
ls: cannot access '/mnt/homedir': No such file or directory
 Desktop                         NVIDIA_CUDA-10.1_Samples
 Documents                       Pictures
 Downloads                       projects
'Handboek Communicatiestijl.pdf' Public
 home                            Templates
 homedir                         Videos
 Music                           work

So the ls command does end up showing the names, but first it says no such file or directory (even though it does recognise files from directories). And I cannot enter the directories or access files -- their permissions all look like this

drwx------ 29 user user 12288 okt 21 15:26 ./
drwxr-xr-x 25 root root  4096 okt 22 14:39 ../
-?????????  ? ?    ?        ?            ? .hiddenfile
d?????????  ? ?    ?        ?            ? directory
-?????????  ? ?    ?        ?            ? normalfile
l?????????  ? ?    ?        ?            ? link

So getting until here gives me the idea that I provide the right passwords etc, but why doe the files and their permissions end up being changed?

Does anyone know if this can be solved by different (encryption) options or by using a different version of ecryptfs?

I am running Ubuntu 18.04 and enabled device encryption during installation. Previously, there came up a nice looking screen and asked for the passphrase for decrypting the drive. I tried to uninstall ghostwriter and executed the command sudo apt autoremove, then I rebooted and now the screen does not appear anymore.

Instead I get an empty purple screen, after approx. 5 seconds the screen color changes to black. Then nothing happens anymore. I then can switch via Ctrl+Alt+F2 and then Ctrl+Alt+F1 to the tty. Here I get a message to failed to connect lvmetad, but I am able to enter the passphrase here and unlock my drive to boot.

How can I repair or reinstall the required packages for the standard passphrase request screen?

EDIT: I am not sure if this might be related, but I also removed 'ghostscript' becuase I confused the apps in the terminal. And then I ran the autoremove. Afterwards I installed ghostscript again.

EDIT 2: It seems autoremove removed a lot of stuff. I was able to find out what packages were removed via:

cat /var/log/dpkg.log | grep remove 

And it showed me this list: List of removed packages (pastebin)

EDIT3: After reinstalling ubuntu-desktop the screen is now back and everything looks fine...

I still will let this post here in case someone experiences the same or an comparable issue.

For establishing a remote connection one must have to enable our OpenSSH server but once we disconnect our connection,is it necessary to stop the SSH service?