M365 Global to 21Vianet migration in Central

A M365 Global to 21Vianet migration project in Central looks simple on a spreadsheet and rarely stays that way. The first question is the one nobody asks outside China: the global Microsoft tenant, or the local 21Vianet service? From there it becomes a design exercise — keeping mail flowing, Teams history intact, and an audit trail your head office can actually read.

For foreign-owned companies in Central we take the whole journey: audit, then tenant and licence design, then cutover, then the settling-in weeks when the odd fault surfaces. The aim is a migration nobody has to talk about afterwards.

Why M365 Global to 21Vianet migration in Central is not like migrating anywhere else

Treat the two clouds as different products, because that is what they are. Licences differ, some features behave differently, and performance comes down to how traffic leaves your office and where it joins Microsoft’s network. Then there is the compliance angle: where personal data may legally sit, and what you can hand to a regulator or a head office when they ask.

Nobody touches a mailbox until the audit is done: what you are licensed for, how Domains and DNS are set, which mail rules exist, how Teams and SharePoint are genuinely used, how identity is configured, and where the devices are enrolled. Typical migrations take two to four weeks end to end.

What we migrate

• Mailboxes, mail flow and shared mailboxes
• Teams and channels, carrying chat history across where the move supports it
• SharePoint and OneDrive content, with permissions checked before and after
• Entra ID, groups, sign-in policy and conditional access
• Endpoint policy and Intune device enrolment
• Domains, DNS records and the licensing picture on the destination tenant

Mailboxes go first and collaboration content follows, so the team keeps working while the rest of the estate catches up.

How a migration runs

1. Audit the current tenant and the actual business requirements
2. Design the destination — tenant choice, licensing, routing
3. Pilot with a small group and measure what really changes for users
4. Cut over in a planned window; we schedule it around your team’s calendar
5. Hypercare — we stay on for hypercare, while the small faults surface
6. Leave you with documentation, and keep supporting the estate afterwards

Where we work

We are not a single-city provider. NETK5 dispatches engineers across mainland China: our own team is based in Shanghai, Beijing, Guangzhou and Hong Kong, and we staff projects elsewhere in the country as clients need them — Xi’an, Chengdu, Taixing and beyond. Outside China we have delivered rack-and-stack work and WiFi surveys in Japan, Korea, Singapore and Taiwan, usually for international companies coordinating several sites from a head office that has never been on site.

For M365 Global to 21Vianet migration in Central that matters in a practical way: work can be planned around a visit rather than a relocation, and the same team that surveys or installs can hand over documentation the head office can actually use.

Where we have done this before

We have supported international businesses in China since 2002, and Microsoft 365 is at the centre of nearly all of it. That includes a pilot migration from the global tenant to 21Vianet for a client operating in China, and the ongoing management of cloud estates — among them more than thirty Azure virtual machines running alongside Microsoft 365. Siemens, Nestlé, McKinsey and JLL are among the names we work with, typically alongside the international IT companies whose client sites we support.

Questions we get asked

Do we have to move to 21Vianet if we are in China?

No. Plenty of foreign-owned companies run on the global tenant and it works. The trade-offs are performance, routing, and how comfortably you can evidence data handling. Some migrations go the other way — from 21Vianet back to global — when a company restructures or leaves. The right answer depends on your users, your regulator and your head office, which is why the audit comes first.

How long are users without email?

In a well-planned cutover, not at all in any meaningful sense: mail flow switches in a window and users sign in again afterwards. What takes time is the settling-in — profiles, devices, shared mailboxes, and the occasional Teams channel that behaves unexpectedly.

Can you support us after the migration?

Yes, and a good share of our migration work becomes ongoing support — helpdesk in English and Chinese, monitoring, and someone who already knows how your tenant was built.

Talk to us about M365 Global to 21Vianet migration in Central

Tell us what you have now and what you need to end up with — tenant, users, sites, and any deadline driving it. We will tell you what the move involves and what it costs before anyone starts.