How can I have a fully compatible with Ubuntu USB that I can read without old user?

[JosiahMaybe]

I know ext4 is fully compatible with Ubuntu. I know FAT and NTFS would lose data. I know there is always an owner with ext4 USBs. As like my question states, how can I have a fully compatible with Ubuntu file system USB that I can access even if read only without old user? By old user I mean user I used to own that USB and write to it. Can I access root owned files like that? I have root owned files on like my Ubuntu 22.04.3 LTS with Ubuntu Pro Lenovo Thinkpad T460 home. Also, could I read from that USB with a Windows computer if I installed correct stuff?

I am trying for full rsync backup with root stuff included. According to some things I could find, rsync can do full recovery too but if anyone ever did that I would like to know. X E.

 

[Chaos]

To create a fully compatible USB with Ubuntu that you can read even if you are not the old user, you can consider the following steps:

1. Format USB with ext4:
   • Format the USB drive with the ext4 file system, which is natively supported by Ubuntu.
     

     sudo mkfs.ext4 /dev/sdX1

   • Replace "/dev/sdX1" with the actual device path of your USB drive.
     
2. Set Appropriate Permissions:
   • After formatting, change the ownership and permissions of the USB drive so that it is accessible by any user.
     

     sudo chown -R $USER:$USER /media/your-username/usb-label

   • Replace "your-username" with your actual username and "usb-label" with the label of your USB drive.
     
3. Read-Only Mount:
   • To mount the USB drive in read-only mode, you can do:
     

     sudo mount -o ro /dev/sdX1 /media/your-username/usb-label

   • Replace "/dev/sdX1" and the path accordingly.
     
4. Access Root-Owned Files:
   • If you have root-owned files on the USB drive, you can still access them by using sudo:
     

     sudo ls /media/your-username/usb-label

   • Enter your password when prompted.
     
5. Access from Windows:
   • To access the ext4 USB drive from a Windows computer, you would need third-party software. One popular choice is Ext2Fsd. Install it on your Windows machine, and you should be able to read from the ext4 file system.
6. rsync Backup:
   • To perform a full rsync backup, use a command similar to the following:
     

     sudo rsync -aAXv --delete --exclude=/dev/* --exclude=/proc/* --exclude=/sys/* --exclude=/tmp/* --exclude=/run/* --exclude=/mnt/* --exclude=/media/* --exclude="swapfile" --exclude="lost+found" / /media/your-username/usb-label

   • Adjust the paths and options based on your requirements.
     

Remember to replace the placeholders (your-username, usb-label, etc.) with the actual values applicable to your system. Always be cautious when working with system files and root permissions to avoid accidental data loss or system instability.

 

[JosiahMaybe]

Thanks, apparently Windows cannot do access to root owned stuff. I think I found how to do rsync and format parts. I did not know that it could be an any user USB. I am a type that will probably just exclude USB at and nothing else. Also, I would use -vaxHAX with rsync. Also, --progress addition is good with rsync.

Anyway, solved, and I do not think I can get full compatability with a Windows system without an installed Linux or bootable USB or possible loss of data by copying as nobody/nogroup. I can record user/group to a file and restore but I do not entirely know this system so what if I lose more than just user and group. Thanks and like solved. there is an option to copy as nobody/nogroup but I do not know if I would lose anything else so I am not taking that chance. Since base of that backup is root owned I would need to either keep a secondary backup for Windows or just forget Windows.

Bootable USB may be a viable option and also WSL temporary or permanent install. With bootable USB I can access root owned files and stuff I think but question is: can I sudo rsync it to a Windows system. I think sudo will work and rsync can operate on NTFS and FAT partitions from Linux so this should work. I have like my own timestamps recorder so I can restore all timestamps on a Windows system if in same or similar directory structure.

I think that bootable USB is how to do Windows compatibility and yes, format a USB to ext4 with Disks or whatever should work. Thanks for extra info. Solved maybe. X E.

 

[JosiahMaybe]

Also I found root on from any user or computer is root on that USB so any sudo is acceptable access sudo. X E.

 

[Chaos]

Thanks, apparently Windows cannot do access to root owned stuff. I think I found how to do rsync and format parts. I did not know that it could be an any user USB. I am a type that will probably just exclude USB at and nothing else. Also, I would use -vaxHAX with rsync. Also, --progress addition is good with rsync.

Anyway, solved, and I do not think I can get full compatability with a Windows system without an installed Linux or bootable USB or possible loss of data by copying as nobody/nogroup. I can record user/group to a file and restore but I do not entirely know this system so what if I lose more than just user and group. Thanks and like solved. there is an option to copy as nobody/nogroup but I do not know if I would lose anything else so I am not taking that chance. Since base of that backup is root owned I would need to either keep a secondary backup for Windows or just forget Windows.

Bootable USB may be a viable option and also WSL temporary or permanent install. With bootable USB I can access root owned files and stuff I think but question is: can I sudo rsync it to a Windows system. I think sudo will work and rsync can operate on NTFS and FAT partitions from Linux so this should work. I have like my own timestamps recorder so I can restore all timestamps on a Windows system if in same or similar directory structure.

I think that bootable USB is how to do Windows compatibility and yes, format a USB to ext4 with Disks or whatever should work. Thanks for extra info. Solved maybe. X E.

You're welcome! It seems like you've got a good understanding of the options available and how to proceed with your backup strategy. Using a bootable USB with Ubuntu or accessing the data through WSL could indeed be viable solutions for interacting with root-owned files on a Windows system.

Remember to exercise caution when dealing with system files and root permissions, and it's great that you are aware of the potential risks associated with copying as "nobody/nogroup" on Windows. It's always a good practice to test your backup and restore procedures to ensure everything works as expected.