Strange behavior when mounting volume on Linux vs Windows
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I'm dual-booting my machine right now with CachyOS linux and Windows 10. A have a few VeraCrypt volumes originally created on Windows on an NTFS formatted disk that I'm trying to use and I'm having issues with one in linux.
One volume when it's mounted in VeraCrypt isn't writable (4.9TB volume) and the other is (3.0TB). Both volumes reside on the same physical disk and in the same directory. The disk they resides on is writable and my user has read, write and execute enabled on both volume files and the mount directory. If I try to copy a file to the 4.9TB volume however I get a message that it's a read-only file system. Checking the volume properties in Dolphin it shows it's writable though.
Output from mount does suggest it's mounted read-only though. Here you can see the difference between the two volumes, 1 and 2:
veracrypt on /tmp/.veracrypt_aux_mnt1 type fuse.veracrypt (rw,nosuid,nodev,relatime,user_id=0,group_id=0,allow_other)
/dev/mapper/veracrypt1 on /run/media/veracrypt1 type ntfs (ro,relatime,uid=1000,gid=1000,dmask=0077,fmask=0077,iocharset=utf8)
veracrypt on /tmp/.veracrypt_aux_mnt2 type fuse.veracrypt (rw,nosuid,nodev,relatime,user_id=0,group_id=0,allow_other)
/dev/mapper/veracrypt2 on /run/media/veracrypt2 type exfat (rw,relatime,uid=1000,gid=1000,fmask=0077,dmask=0077,iocharset=utf8,errors=remount-ro)
So why exactly is VeraCrypt mounting it "ro" vs "rw" and is there anyway I can change that? Not sure if it matters but I'm using VeraCrypt version 1.26.24 on Linux, whereas on Windows I'm using 1.25.9.
One of the containers is NTFS internally and one is exfat. It's possible the container's NTFS is dirty (needs a scan done). Windows is more lenient mounting dirty volumes VS Linux. I would open the volume in Windows and do a scan/repair from there. You can do so in Veracrypt's main window. Right click the mounted volume > check filesystem.
Thank you for the reply Alex.
This seemed to have a bad and good effect. Scanning the drive in Windows found no issues. When I returned to Linux and attempted to mount the drive, I received the following error:
device-mapper: create ioctl on veracrypt1 failed: Device or resource busy
Command failed.
This was of course not encouraging. I returned to Windows and checked the volume further... no problems and everything seemed to work ok, but returning to Linux and received the same error again. However this time I happened to have Dolphin open and noticed the drive showed up mounted despite the error. As you can see in the screenshot, the 4.9TiB mount is visible in Dolphin but VeraCrypt shows nothing mounted.
It shows up a bit different in the mount output now too:
/dev/mapper/veracrypt1 on /run/media/tim/447EC5337EC51F14 type ntfs3 (rw,nosuid,nodev,relatime,uid=1000,gid=1000,iocharset=utf8,uhelper=udisks2)
Not quite sure why the mount location is different. It works though. I can read from it and I was able to save a file to the volume, but it's very weird that it doesn't show up in the VeraCrypt UI. Not sure if I should be worried or not.
Thought I'd add this here just in case it helps others.
Even after the above Veracrypt mounting behavior wasn't consistent and often the volume mounted read-only. The real problem seemed to be that while CachyOS has ntfs support built-in, it doesn't have the ntfs-3g package installed by default and installing that makes the ntfs support work much better. After doing so my problematic volume mounted consistently with rw access.