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Permalinks on PMSS

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Every active Pulsed Media seedbox and storage box gets a permalink — a permanent hostname under mcx.fi that points to your service and follows it when we move it to a different server. Bookmark it, put it in a webhook, use it as an API base; it does not change when your underlying server does.

The permalink is a short hash label, so it carries no username and no account number in the address. You compute your own from your service ID — nothing has to be looked up or requested.

The two permalink forms

Form Looks like Points to
Service permalink (one per service) {hash}.mcx.fi the single server your service runs on
Cluster permalink (accounts with 2+ services) {hash}.mcx.fi all of your servers, in round-robin

Both are live in DNS today. Both labels are a truncated SHA-256 hash — nothing else. The service permalink also serves your public web folder over HTTP; the cluster permalink resolves but does not serve web content yet — see web hosting and the note below.

Service permalink — one stable hostname per service

Each active service has its own hostname built from its service ID. The label is the first 16 hex characters of a SHA-256 hash:

label = first 16 hex chars of  sha256("mcx.fi:service:<your service ID>")
url   = <label>.mcx.fi

The service ID is the number in your client area product page URL — clientarea.php?action=productdetails&id=<service ID>. Compute your permalink on any machine with sha256sum:

printf 'mcx.fi:service:12345' | sha256sum | cut -c1-16
# -> a hex label; your URL is <label>.mcx.fi

Replace 12345 with your own service ID. The hash uses no secret — the same input always gives the same label — so your permalink is stable for the life of the service. When we migrate your service to another server, the record updates to the new server's address automatically; the hostname stays the same.

Cluster permalink — round-robin across your servers

If your account has two or more services on different servers, you also get one cluster permalink built from your client ID:

label = first 16 hex chars of  sha256("mcx.fi:customer:<your client ID>")
url   = <label>.mcx.fi

This hostname carries an address record for each of your servers, handed out in rotating order, so connections spread across your servers — a simple round-robin at the DNS level. It gives you one name that reaches your whole fleet, with the lookup landing on a different server each time.

This is plain round-robin DNS, not a health-checked load balancer and not an edge CDN. There is no failover: a server that is temporarily down stays in the rotation until it is removed on a later rebuild. It spreads load; it does not detect outages.

The cluster permalink does not serve your web content yet. It resolves correctly — a lookup lands on one of your servers — but that server answers with its own default page rather than your ~/www/public/, because the cluster name is not yet attached to your web configuration. For web links today, use a service permalink, which does serve your content. Cluster-name serving is a planned addition; until it ships, treat the cluster permalink as a DNS-level convenience for non-web use.

What gets served at these hostnames

Your service permalink resolves to the server your service runs on. On the current Pulsed Media platform it serves your public web folder, ~/www/public/ — the same content as your per-user web hosting. So a file at ~/www/public/report.pdf is reachable at http://<service-label>.mcx.fi/report.pdf.

Your cluster permalink is not a web address today — see the note in the cluster section above. It resolves to your servers, but web requests to it get the server default page rather than your content.

Web serving here is over plain HTTP. A browser opening https:// on these names will warn, because the server's TLS certificate is issued for its own hostname, not for the mcx.fi label. For an HTTPS link today, use your server's own hostname.

Why the permalink is stable

The label comes from your service ID, which never changes, so the hostname is permanent. The address behind it is rebuilt from live account data, so it tracks reality: a migration to new hardware updates the address, a cancelled service drops out. The records carry a long time-to-live (about a day), so after a migration it can take up to a day for every resolver to see the new address. The trade-off is deliberate — the permalink is meant to be stable, not instant.

Privacy

The permalink is a hash label, so your username is not in the address. Only the hash and the IP are ever published to DNS — your service ID, client ID, and username stay on our systems and are never sent out. The hash is computable rather than secret: anyone who knows a service ID can derive its label, and the address it points to is public DNS like any hostname. Treat these permalinks as public links, not as private ones.

Included with every service

A permalink comes with every active seedbox and storage box at no extra cost, on the same PMSS platform that runs the fleet. Put a file in ~/www/public/, hand out the mcx.fi permalink, and it keeps working when your service moves.

See also