Problem decryption disk

[bruno pinto]

Hello,
When I encrypt my client's disk with cryptsetup, at the end of the installation it reboots. 
Everything is going well. 
But when it boots after install, the boot sends me to the initriamfs. 
We think he can't decrypt the encrypted disk. Thomas told me about a package story. I already have the cryptsetup package configured on my server but do I need to put other packages that are unknown to me.
Anyone could help me?
Kind regards,

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