Cluster Site Reliability Engineer

Cluster & SRE

Cluster Site Reliability Engineer

Own the physical reality of the platform in one of our seven regions. You bring up new GPU racks, validate InfiniBand fabric end-to-end, and keep the cluster running at the SLA. This is a hands‑on role; you will see the hardware.

Team Cluster & SRE

Location: On‑site

• Cologix region of choice (Toronto, Montréal, Columbus, Vancouver, Ashburn)

Type: Full‑time

Stack

• Linux
• InfiniBand (NDR / XDR)
• NCCL / RCCL
• Kubernetes (host-level)
• Terraform
• Prometheus / Grafana
• Go or Python

About The Team

Cluster SRE is six engineers across the seven regions. Each region has a primary and a secondary; you will be one of those for your region. The team coordinates daily, deploys weekly, and rotates a global pager.

Reports to the head of cluster engineering. Primary on a single region; rotates secondary for one neighboring region.

The role

What you'll do

• 01 Bring up new B200 / B300 / MI300X racks: cabling, ToR config, NCCL/RCCL all-reduce validation, MFU baseline tests.
• 02 Drive InfiniBand fabric to spec — NDR / XDR depending on the rack — and chase residual bit-error budget down to zero.
• 03 Run capacity planning across seven regions: forecast demand, model power and thermal headroom, work with procurement on lead times.
• 04 Own the regional incident response. P1 incidents page within fifteen minutes; resolution target is four hours.
• 05 Build and maintain the bring‑up runbook so the second hire after you can do their first rack solo.
• 06 Carry the global pager about one week per six, alongside runtime and customer engineering.

What we're looking for

• Five-plus years operating large compute clusters — supercomputing centers, hyperscaler infra, or HPC at a national lab count.
• Deep InfiniBand and Ethernet RoCE experience: subnet manager tuning, fabric debugging, lossless networking.
• Strong Linux fundamentals: kernel parameters, NUMA topology, kernel cgroup limits.
• Comfort writing Go or Python for tooling. We are not strict about which.
• Calm under load. You will be the named person on a $50M-ARR account when something goes wrong.

Bonus

Nice to have, not required

• DGX H100 / H200 / B200 bring‑up history.
• Experience with NVIDIA Bright / Base Command Manager.
• Bare‑metal provisioning systems: Tinkerbell, MAAS, Razor, or in‑house equivalents.
• Procurement / vendor management experience.

Compensation

In writing, like everything else

Base $210,000 – $340,000 USD (US Cologix regions) / equivalent in CA.

Equity Meaningful early‑stage equity, refreshed on tenure milestones.

Notes

On‑site pay differential at Cologix regions outside SF / NYC / Bay Area is +5–10% to compensate for travel.

Equal opportunity

We hire on the work. Race, gender, age, nationality, religion, sexual orientation, disability, and veteran status do not factor into our decisions. We sponsor visas for senior roles in the US, UK, and EU — bring it up on the manager call.

Need an accommodation for the interview process? Mention it in your application or write .