ECryptfs in Arch Linux not running with an error, “ERROR: Cannot get ecryptfs version, ecryptfs kernel module not loaded?”

Question

I was following the ECryptfs Arch Linux setup instructions, and ran into this problem:

root@alarm:~# ecryptfs-setup-private --nopwcheck --noautomount 
ERROR:  Cannot get ecryptfs version, ecryptfs kernel module not loaded?

This is on a newly created Arch Linux machine:

root@alarm:~# uname -a
Linux alarm 4.2.0-1-ARCH #1 PREEMPT Wed Sep 2 07:00:18 MDT 2015 armv5tel GNU/Linux

I subsequently tried building and installing ecryptfs-utils from source, but I get the same error.

I also tried manually creating a secret directory according to the Arch Linux ECryptfs wiki, but I get this error:

root@alarm:~# mount.ecryptfs_private secret
mount: No such device

And when I try mounting without any of the utils scripts, I get this:

root@alarm:~# mount.ecryptfs /root/.secret /root/secret
Unable to get the version number of the kernel
module. Please make sure that you have the eCryptfs
kernel module loaded, you have sysfs mounted, and
the sysfs mount point is in /etc/mtab. This is
necessary so that the mount helper knows which 
kernel options are supported.

Make sure that your system is set up to auto-load
your filesystem kernel module on mount.

Enabling passphrase-mode only for now.

Unable to find a list of options to parse, defaulting to interactive mount
Select key type to use for newly created files: 
 1) passphrase
 2) openssl
Selection: 1
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]: 
Error attempting to evaluate mount options: [-22] Invalid argument
Check your system logs for details on why this happened.
Try updating your ecryptfs-utils package, and/or
submit a bug report on https://bugs.launchpad.net/ecryptfs

Answer 1

Old thread, but I wanted to post the solution for future reference.

You only need to run the ecrpyptfsd commad before any other ecryptfs programs. This will load the necessary modules for the other commands to work.