Ssh Access And Routing Without Host Header
Key takeaways
- exe.dev identifies the customer account using the presented SSH public key and uses that identity to forward the connection to the correct underlying VM.
- exe.dev avoids assigning every VM a globally unique IP by ensuring each VM has an IP address that is unique within a given customer account.
- exe.dev charges $20/month and provides up to 25 VMs that share a pool of 2 CPUs and 8GB RAM.
- When a user creates multiple VMs on exe.dev, each VM resolves to a different IP address, and those IPs are shared with many other users.
- Users can SSH into an exe.dev VM using a hostname of the form <vmname>.exe.dev.
Sections
Ssh Access And Routing Without Host Header
The corpus asserts that hostnames are used for SSH access and that routing to the correct VM is achieved despite SSH lacking an HTTP-style Host header. The stated mechanism is that the provider uses the presented SSH public key to identify the customer account and then forwards the connection accordingly, implying routing is coupled to authentication identity.
- exe.dev identifies the customer account using the presented SSH public key and uses that identity to forward the connection to the correct underlying VM.
- Users can SSH into an exe.dev VM using a hostname of the form <vmname>.exe.dev.
- exe.dev can route an SSH connection for <vmname>.exe.dev to the correct VM even though SSH lacks a Host-header equivalent for name-based routing.
Per Account Ip Uniqueness And Shared Ips
The corpus describes an IP allocation approach where VM IP uniqueness is guaranteed within an account rather than globally, and where resolved IPs are shared across many users. This is consistent with a multi-tenant design that reduces the need for globally unique per-VM IP addresses, but the corpus does not specify isolation boundaries, security controls, or failure modes.
- exe.dev avoids assigning every VM a globally unique IP by ensuring each VM has an IP address that is unique within a given customer account.
- When a user creates multiple VMs on exe.dev, each VM resolves to a different IP address, and those IPs are shared with many other users.
Bundle Pricing And Resource Pooling
The corpus specifies a single-price bundle that allows many VMs under one subscription while sharing a fixed CPU/RAM pool. This defines an explicit oversubscription/resource-sharing model that is likely to shape performance expectations and cost structure, but the corpus does not quantify performance or enforcement details.
- exe.dev charges $20/month and provides up to 25 VMs that share a pool of 2 CPUs and 8GB RAM.
Unknowns
- How strictly are the 2 CPU / 8GB RAM pool limits enforced across the up-to-25 VMs, and what are the observable performance/latency characteristics under contention?
- At what stage does exe.dev determine the account identity from the SSH public key (pre-auth routing vs post-auth forwarding), and what happens on authentication failure?
- How does exe.dev handle a public key that is added to multiple customer accounts (conflict), and is such reuse allowed or prevented?
- How are per-account-unique VM IP addresses assigned and maintained over time (persistence, recycling, reassignment), and what triggers changes?
- What tenant-isolation and reputation/rate-limit mitigations exist given that many users share the same public IPs?