The m5zn.metal pairs 48 vCPU with 192 GiB of RAM, the 4.00 GiB-per-vCPU ratio that marks a general-purpose instance. In the name, "m" is the general-purpose line, "5" is the generation, "zn" marks a higher clock and enhanced networking and "metal" is the size within the m5zn family. It runs on Intel Xeon Platinum 8252 at 4.5 GHz, and AWS introduced it in December 2020. AWS has since shipped m6i, m7i, m8i and m9g; m6i.metal is the direct replacement at this size. Spot's node ladder tops out below this size, so m5zn.metal becomes 3 × gp.vs1.2xlarge (48 vCPU, 192 GiB combined), $3.96/hr on AWS in US East (N. Virginia), from $0.123/hr on Rackspace Spot. Spot delivers compute as managed Kubernetes, so a node pool of that size is the native shape of the answer rather than a workaround — provided the workload scales horizontally.
Match qualityVirtualised, not bare metal
m5zn.metal is a full physical server — no virtualisation layer in the way, direct access to the hardware, and a socket count that licensing can verify.
Rackspace Spot no longer sells bare metal; everything in the catalog is a virtual machine. You get the same cores and memory (3 × gp.vs1.2xlarge, 48 vCPU, 192 GiB), but not the dedicated hardware. If you picked m5zn.metal because you needed the real machine — nested virtualisation, per-socket licensing, low-level profiling — this is not a replacement at any price. If you picked it because it is the biggest m5zn, it is the same compute for a lot less.
Runs as a fleetNo single Spot node has 48 vCPU; the largest comparable one has 16. So this runs as 3 nodes. That works if your workload already spreads across machines, and doesn't if one process needs all the cores together.
