Setup & operation
Is outbound port 25 open, so I can run a mail server?
Yes, outbound port 25 is open on every OnionVPS instance by default. There is no support ticket, no account-age requirement and no paid unblock. Most providers block it permanently to control spam, which is why self-hosted mail is impossible on much of the market.
Open port 25 is necessary but not sufficient for deliverability. You also need a matching reverse DNS record, SPF, DKIM and DMARC, and address space with no spam history. We provide the first and the last; the DNS records are yours to publish.
Warm a new address up gradually. A few dozen messages a day for the first week, growing steadily. A volume spike from a new IP looks exactly like a compromised host, because usually it is one.
See also: Reverse DNS · Port 25 · DMARC · DKIM
7 answers in Setup & operation
- How do I connect to a VPS with SSH? Run ssh root@your-server-ip from any terminal on macOS, Linux or Windows 10 and later. Use the key you supplied at provisioning, or the password email…
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- How do I set up a firewall on a VPS? Use nftables on modern Linux, or ufw as a friendlier front end. Set the default inbound policy to drop, allow established and related connections, the…
- Can I install any operating system on a VPS? On KVM, yes. OnionVPS provides templates for Ubuntu, Debian, AlmaLinux, Rocky, Fedora, Arch, Alpine, NixOS, FreeBSD, OpenBSD, Windows Server, Proxmox …
- Can I upload my own ISO? Yes, on every plan, at no cost and with no approval step. Upload the ISO from the panel or point us at a URL, attach it as virtual media, and boot fro…