Decommissioning an old server gracefully

I put every site behind the same free CDN tier and forgot about DDoS worries.

Staging is just a subdomain plus a database copy — nothing fancy, works fine.

Learned the hard way that an untested backup is a Schrödinger backup.

My monitoring setup alerts me within a minute of downtime and costs nothing.

Would love to hear how you all handle this.

Any tips, experiences or strong opinions welcome.