Next 3 days I' ll be working on moving our email server to new server because the old datacenter is closing down. Clients are pissed and they are fucking verbally bashing me left to right when I told them that their emails will be down since most of them host their own DNS.

I am fucked.

Oh man! Honestly... good luck!

I really dont see the problem. The only thing you need to tell them is when they can update their DNS mx record once you have moved your mailserver. I'm guessing transferring the machines is going to take a while so do the move somewhere around midnight.

Seriously, once you moved, changed your IP config settings, just give your customers the new IP address where to point their MX record and done.

@NeatNerdPrime that part is okay. The worst part clients doesn't have IT team. We will have to TeamViewer on their PC and change their mail setup details. We have also 800 Users mailbox.