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Osto encrypts both legs of every request — between the user and Osto, and between Osto and your origin. There are two ways to control which certificate Osto presents:
  1. Auto-generate — Osto provisions and renews a free SSL certificate for you (ACME-based, requires a one-time CNAME at your DNS provider).
  2. Bring your own — you upload your own certificate bundle and Osto uses it.
This page describes managing the certificate pool you can pick from when you choose option 2. The auto-generate flow happens entirely inside the Add Website wizard — see Managing Websites & Subdomains.
Path: Assets → Domains → Manage Certificate

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The certificate list

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Adding an SSL Certificate

Certificates land in your pool from two places:
  1. Directly here, via Add Certificate + on this page.
  2. Inside the Add Website wizard, when you uncheck Auto-generate certificate and upload a ZIP — that upload is added to the pool for future reuse.
To add one from this page:
1

Navigate to Manage Certificate

Go to Assets → Domains → Manage Certificate.
2

Open the upload dialog

Click Add Certificate +.
3

Upload your certificate archive

In the Upload Certificate Archive dialog, drag-and-drop or click to upload a .zip file containing your certificate bundle.The ZIP must contain valid certificate files (.crt or .pem) and private key files (.key or .pem).
4

Confirm the certificate appears

The certificate appears in the list with its Name, Valid To, Status, and Managed By columns populated from the bundle contents.
The upload accepts only a single .zip file. If you have separate cert and key files, package them together into a ZIP before uploading.

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Editing a certificate

There is no edit action on this page. To replace or update a certificate (for instance after renewal), delete the existing one and upload the new one. Domains that referenced the old certificate will pick up the new one automatically, as long as the new cert covers the same domain.

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Deleting a certificate

  1. Click the Delete button on the certificate’s row.
  2. Confirm.
A certificate can’t be deleted while it’s actively serving traffic for a registered domain. Switch the domain to Auto-generate, or upload a replacement first, before deleting an in-use cert.

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Tips

  • Wildcard certificates simplify operations. One *.example.com upload covers every subdomain you register. Use them unless you have a compliance reason to issue per-host.
  • Don’t have a certificate? Use the Auto-generate certificate option in Add Website — Osto handles provisioning and renewal for you.
  • Track your own renewal cycle for uploaded certs. Osto surfaces expiry in the Valid To and Status columns and in alerts, but renewal happens at your CA.