Proxmox VE
Proxmox VE is an open-source server virtualization platform built on KVM and LXC. It provides a web-based management interface for running virtual machines on physical hardware. Pulsed Media uses Proxmox as the hypervisor layer across its entire seedbox fleet.
How Pulsed Media uses Proxmox
Every shared seedbox at Pulsed Media runs inside a KVM virtual machine managed by Proxmox. The physical servers in the Helsinki and Kerava datacenters run Proxmox VE on bare metal. Each physical host runs multiple VMs, typically housing 10 to 26 seedbox users depending on the product tier.
Each VM runs Debian Linux with PMSS, the software stack that provisions and manages individual user accounts. Pulsed Media has been running this architecture since at least 2015.
The Proxmox web interface is admin-only infrastructure. Customers do not access it — all customer-facing access goes through the PMSS web panel, SSH, and FTP.
Architecture
The full stack from hardware to user account:
| Layer | Component | Notes |
|---|---|---|
| Physical server | Bare metal x86 host | Helsinki or Kerava datacenter |
| Hypervisor | Proxmox VE (KVM) | Manages all VMs on the host |
| Virtual machine | Debian + PMSS | One VM per group of users |
| Per-user services | rtorrent, lighttpd, proftpd | Managed by PMSS, one set per user |
| User access | PMSS web panel, FTP, SSH | SERVER.pulsedmedia.com/user-USERNAME/
|
Why Proxmox
Proxmox VE is GPL-licensed with no per-socket or per-VM licensing fees. Running a fleet of servers with multiple VMs per host makes per-VM licensing costs from proprietary hypervisors significant.
Proxmox integrates directly with KVM and the Linux kernel, which matters for the raw block device passthrough that PM's storage architecture depends on. The web UI and API make cluster-wide management workable without per-host SSH sessions for every routine task.
Storage architecture
Each VM gets its storage as a raw block device passed through directly — not a disk image file. The physical storage stack:
Physical HDDs
↓
bcache device (some hosts — SSD cache layer)
↓
MD RAID array (/dev/mdXXX)
↓
VM raw block device passthrough (virtio-scsi)
↓
VM sees a single disk → ext4 filesystem
The RAID type matches the product line:
- V-series (V1000, V10G) — RAID 0 across two drives. Full speed, no redundancy.
- M-series (M1000, M10G) — RAID 5 across four to six drives. Single-drive failure tolerance.
- Dragon-R — RAID 10 on 20Gbps EPYC servers.
MD RAID arrays are numbered to match VM IDs — md104 feeds VM 104. This makes storage-to-VM mapping straightforward during diagnostics.
Some hosts include a bcache layer between the physical HDDs and the MD arrays. Bcache uses a smaller SSD as a read/write cache in front of the HDD array, improving random I/O performance.
VPS customers
Customers on VPS plans get a dedicated VM on a Proxmox host rather than a shared account inside a VM. The isolation model is the same — KVM virtualization — but the VM is theirs alone, with root access and no other users sharing the OS instance.
See also
- PM Software Stack — the management software running inside each VM
- RAID — storage redundancy for each product line
- Pulsed Media Datacenters — where the hardware lives
- Debian — the OS running inside each VM
- Seedbox — what customers actually use