I know that it's old, but I had the same problem. Maybe it can help others.
My fstab was quite the same as @Alan Pope's, and my crypttab was...
cat /etc/crypttab cryptswap1 /dev/sdb3 /dev/urandom swap,cipher=aes-cbc-essiv:sha256
I found that my swap device should be /dev/sda3 instead of /dev/sdb3. So, just changing /etc/crypttab contents to
cryptswap1 /dev/sda3 /dev/urandom swap,cipher=aes-cbc-essiv:sha256
solved my problem.
I know that it's old, but I had the same problem. Maybe it can help others.
My fstab was quite the same as @Alan Pope's, and my crypttab was...
cat /etc/crypttab aes-cbc- essiv:sha256
cryptswap1 /dev/sdb3 /dev/urandom swap,cipher=
I found that my swap device should be /dev/sda3 instead of /dev/sdb3. So, just changing /etc/crypttab contents to
cryptswap1 /dev/sda3 /dev/urandom swap,cipher= aes-cbc- essiv:sha256
solved my problem.