MUM-2 opened in February 2023 next door to MUM-1 on the Navi Mumbai campus, with 6.3 MW of IT capacity over 110,631 square feet — 17,560 sq ft per megawatt, about 57 watts per square foot. That makes it the densest building in Iron Mountain’s Indian portfolio and the newest thing the company operates in Mumbai. It is also the interconnection site of the campus: nine carriers, more than 200 ISPs and four internet exchanges — DE-CIX, AMS-IX, Extreme IX and NIXI. And like MUM-1 it counts as zero megawatts in this registry, because the capacity field was left blank.
1At a glance
2The densest building in the portfolio
MUM-2 is where the campus’s engineering actually lives, and the density numbers show it.
| Building | MW | Sq ft per MW | Watts per sq ft |
|---|---|---|---|
| MUM-2 | 6.3 | 17,560 | 56.9 — highest |
| MUM-1 | 2.5 | 20,000 | 50.0 |
| BLR-1 | 4.0 | 20,000 | 50.0 |
| HYD-1 | 5.5 | 21,818 | 45.8 |
| PUN-1 | 2.0 | 25,093 | 39.9 |
| NCR-1 | not disclosed | — | — |
| MUM-3, at full build | 85 | 16,447 | 60.8 |
MUM-2 carries 2.5 times MUM-1’s output on 2.2 times its floor area. That is the only genuine density gain in the operating estate, and it was delivered by a building next door on the same five and a half acres.
A 6.3 MW building at 57 watts per square foot is a colocation business. An 85 MW building at 61 watts per square foot is a leasing business. The watt density is nearly identical; the customer, the contract length and the capital structure are not.
That is why the campus can credibly hold both. MUM-1 and MUM-2 sell cabinets and cages. MUM-3 sells wholesale suites to hyperscalers for twenty years at a time.
3Nine carriers, 200 ISPs, four exchanges
Interconnection is the part of a data centre that cannot be rebuilt quickly and is the real reason tenants stay. MUM-2 is the campus’s network anchor.
| Element | Detail | Why it matters |
|---|---|---|
| Carriers on site | 9 | Physical diversity into the building |
| Internet service providers | more than 200 | The demand side of the exchange |
| Internet exchanges | DE-CIX, AMS-IX, Extreme IX, NIXI | Four separate peering fabrics in one facility |
| Cloud on-net | All major cloud providers, per the operator | Direct connect without leaving the building |
| Deployment options | Cabinets, dedicated cages, custom build on raised floor | Sells to enterprises, not just hyperscalers |
| Uptime design | Concurrently maintainable Tier III | The standard enterprise procurement gate |
Four internet exchanges inside a single 110,000 sq ft building in Navi Mumbai is the strongest interconnection claim this registry has recorded for a sub-10 MW facility. It is also the least replicable asset Iron Mountain owns in India: an 85 MW shell can be built in two years, and a peering ecosystem cannot.
Capacity is a commodity priced per kilowatt. Interconnection is not: the same megawatt in a building with four exchanges and 200 ISPs is worth more than the same megawatt in a shell on the fringe of the city, and it is worth more every year as the ecosystem deepens.
This is the argument for valuing Indian data centres on interconnection density rather than megawatts. The registry records both, which is why the MUM-2 record carries the exchange names and not just the number.
4The floor area the file gets wrong
The source file records MUM-2 at 100,000 sq ft / 9,300 sq m. The operator now publishes 110,631 sq ft / 10,278 sq m. The difference is 10,631 square feet, 10.6%.
| Metric | At 100,000 sq ft | At 110,631 sq ft | Effect |
|---|---|---|---|
| Sq ft per MW | 15,873 | 17,560 | Density looks 10.6% better than it is |
| Watts per sq ft | 63.0 | 56.9 | Power density understated by 6.1 W |
| Share of the 480,552 sq ft estate | 20.8% | 23.0% | A fifth becomes nearly a quarter |
| Campus area reconciliation | 480,552 vs 484,000 — 0.12% apart | Only reconciles with 110,631 | The corrected figure is the one that fits |
The correction is not cosmetic. With MUM-2 at 110,631 sq ft, the six operating facilities sum to 480,552 sq ft, which is within 0.12% of the platform’s stated 484,000 sq ft / 44,700 sq m. With MUM-2 at 100,000 sq ft the sum is 469,921 sq ft and the platform figure no longer reconciles.
That is how a source error gets caught: not by checking one number, but by checking whether the parts add to the whole the same company published independently.
5Procurement
6Limits and open questions
- 6.3 MW is IT capacity with phased deployment. One operator FAQ says 6 MW; the location page says 6.3 MW. Both are live.
- The operator states 8.3 MW for MUM-1 and MUM-2 combined, which does not equal 2.5 plus 6.3. The 8.3 figure is older and is used in the campus 93 MW total.
- The 110,631 sq ft figure is a whole-building measurement, so 56.9 W per sq ft understates the density in the halls.
- Carrier and ISP counts are operator statements and are not independently verified by this registry.
- Four internet exchanges in one building is unusually high for a sub-10 MW facility and is the operator’s own claim.
- The count is zero. This page explains a gap in the registry rather than changing the total.
- What would close it. A capacity value in the source field; the operator has published one since 2023.
7Sources
Sources: the Iron Mountain MUM-2 location page; the Iron Mountain Mumbai campus page; the Iron Mountain Data Centers India platform page; the February 2023 opening coverage; and the Web Werks MUM-2 facility page.