Installed Kali on external HDD but boot fails (ALERT! /dev/sdc3 does not exist. Dropping a shell)

[Fazolette]

Hello

I have installed Kali on my USB hard drive, during the install I have chosen the manual partitioning to install on the usb hdd.
The install went through without issues.

When I reboot my mac (with rEFind installed) the kali entry pops up, and goes into that blue Kali screen to chose to boot on it.
Once it boots it fails at the begining with this error

[HTML]Gave up waiting for root file system device. Common problems:
- Boot args (cat /proc/cmdline)
- Check rootdelay= (did the system wait long enough?)
- Missing modules (cat /proc/modules: ls /dev)

ALERT! /dev/sdc3 does not exist. Dropping a shell[/HTML


During the install though I'm pretty sure I saw the external hdd being called "sdb" and to "sdc"

Why did this happen? How can I debug / fix this ?

Thanks!

[Fazolette]

Update:

Just noticed it strangely tried to load sdc3??
I had clearly set the root device to be /dev/sdb3 during the install, why is it trying to load sdc ?

I have entered 'e' to configure GRUB and tried changing on the fly the root target and it boots Kali just fine.

[Mister_X]

I haven't done this in years but my guess is that the disk is going to be called sda, so in this case just edit the boot drive.

It was called sdc because you had 2 disks on the system when you installed it and this one was the third one at the time.