Zero-Downtime Website Migration: The Both-Servers-Live Method

The fear is justified: done in the wrong order, a host migration shows visitors a dead site and bounces your email for a day. Done in the right order, both servers run in parallel and the switch is invisible. This is the right order.

Phase 0: Preparation (two days before)

• Inventory: website files, database(s), email accounts and their contents, cron jobs, SSL needs. Missed email is the classic migration casualty; list every mailbox now.
• Lower DNS TTL: at your DNS provider, set the domain's records to a 300-second TTL. Currently it is likely hours; the switch later becomes near-instant because of this one change. This step is why you started two days early.
• Access check: logins for old host, new host, and domain/DNS control. Migrations stall on missing passwords more than on technology.

Phase 1: Copy everything (old site stays live)

1. Files: full backup or zip of public_html from the old host; upload and extract on the new one.
2. Database: export from old phpMyAdmin, create database and user on the new host, import, and update the site's config file with the new credentials.
3. Email: recreate every mailbox on the new server. Historical mail moves via IMAP sync tools, or, on cPanel-to-cPanel moves, rides inside a full account transfer automatically. WebsNP migrates all of this free for arriving customers, which turns this whole phase into "send us your old login".

Phase 2: Test the new copy before anyone sees it

Trick your own computer into viewing the new server while the world still sees the old: edit your hosts file to map your domain to the new IP (or use the preview URL your new host provides). Click everything: pages, forms, admin login, a test order if you sell. Fix what is broken now, at leisure, invisibly. This phase is the entire secret; people who skip it debug in public.

Phase 3: The switch (five calm minutes)

Update DNS to the new server: nameservers or the individual A records. With your lowered TTL, the world follows within minutes. New visitors hit the new server; stragglers on cached DNS still reach the old one, which is running the same site, so nobody anywhere sees an error. This overlap is the zero in zero-downtime.

Phase 4: The overlap week

• Keep the old hosting active several days. Check its mail server for late-arriving messages and sync them across.
• Confirm SSL issued on the new server (automatic once DNS points there).
• Watch the new server's error log for surprises with real traffic.
• Only then cancel the old plan, and restore the TTL to a normal value.

The rollback plan you will probably never use

Because the old server stayed untouched, your rollback is: point DNS back. That is it. Migrations with this property are low-stakes experiments; migrations without it are trapeze work. Never cancel the old host to save four days of fees before the week is out.

Or hand it to us

Every WebsNP hosting plan includes free migration: we run this exact sequence, you approve the tested copy, we switch. Your involvement is one email and one look at the preview. Either way, now you know what good looks like, and you will never again accept downtime as a migration tax.