The vault user created by the vault package is now a member of the daemon
class, which will allow it to use mlock() when started by the rc script. This
will not be reflected in systems where the user already exists. Please add the
vault user to the daemon class manually by running:

pw usermod -L daemon -n vault

or delete the user and reinstall the package.

You may also need to increase memorylocked for the daemon class in
/etc/login.conf to 256M or more and run:

cap_mkdb /etc/login.conf

Or to disable mlock, add:

disable_mlock = 1

to %%PREFIX%%/etc/vault.hcl