Drawback of Multi Level Encryption

I am backing up my files to a RAID mirrored HDD, that has full disk encryption (FDE) in place with LUKS. Until now I did this with rsync, but I recently switched to a new backup program that does file level encryption as well.

So my question is: Is there any drawback of having multi levels of encryption, or is it actually an advantage? A drawback I can maybe think of would be managing two keys and forgetting one of them would potentially make my backup completely useless.

Multi check are too easy?

When asking for a skill check that all the players can attempt, it is quite easy to have at least one player to succeed.

Indeed, a 15 DC investigation (that is a 30% chance with a +0) is quite easy for a group of 5 PC (83% chance to succeed). Even a 20 DC would not be that difficult if there is enough people with a +3/+4.

How to manage group check to avoid the check to be too easy ?

To notice that I am not talking about a group check (in that case it looks that half+ of the player need to succeed), but rather a check that everyone can attempt one at a time (opening a safe, decipher a scroll, looking at an ancient item to know its history…)

Does Thirsty Blade from Eldritch invocations stack with multi attack?

My DM is open to odd characters and is letting me play a true lycanthropy weretiger in DnD 5e. We went over the entry in the monster manual for weretiger and decided what modifications should be made and he told me to include the multiattack feature and I believe to ignore the specificity of weapons (though I’m sure exclusions should still apply to say 2 handed melee weapons and heavy weapons). He was fully aware that I would be playing the warlock class and taking the pact of the blade. My question is, if I take the Eldritch invocation thirsty blade, will that stack with multiattack? If so, will I attack twice for both of those attacks giving me 4 physical attacks per turn at times?

Risk of having Azure Multi Site-To-Site VPN with different client

My company decided to build an ETL server on Azure and share by multiple client. My task is to research on possibility to set up multiple VPN tunnel from cloud to multiple client office network. I feel that it will have security concern, but this is just my opinion, can anyone help me to list out the risk? Should i proceed?