ubuntu 18.04 volume not mounted

There could be a few reasons why a volume is not mounted in Ubuntu 18.04. Here are some steps you can try to troubleshoot the issue:

1. Check if the volume is detected: Run the `lsblk` command to see if the volume appears in the list of available drives. If it doesn't, there might be a problem with the physical connection or the drive itself.

2. Mount the volume manually: If the volume is detected but not automatically mounted, you can try mounting it manually. Create a directory where you want to mount the volume (e.g., `sudo mkdir /mnt/myvolume`), and then use the `mount` command to mount the volume (e.g., `sudo mount /dev/sdb1 /mnt/myvolume`). Replace `/dev/sdb1` with the actual device name of your volume.

3. Check file system errors: If the volume is still not mounting, there might be file system errors on the drive. Run a file system check using the `fsck` command. For example, if the volume is `/dev/sdb1`, run `sudo fsck /dev/sdb1`.

4. Verify the file system type: Ensure that you are using the correct file system type for the volume. For example, if it's an ext4 file system, make sure to use `sudo mount -t ext4 /dev/sdb1 /mnt/myvolume` for mounting.

5. Check for compatibility issues: If the volume was previously used with another operating system or device, there might be compatibility issues. Make sure that the file system and partition type are supported by Ubuntu.

6. Check for errors in logs: Look for any error messages related to the volume in the system logs (`/var/log/syslog`). This can provide additional information about why the volume is not mounting.

If none of these steps work, please provide more details about your specific setup and any error messages you encounter, so that I can assist you further.