Certificates for communication within the cluster
Each Proxmox VE cluster creates its own (self-signed) Certificate Authority (CA) and generates a certificate for each node which gets signed by the aforementioned CA. These certificates are used for encrypted communication with the cluster’s pveproxy service and the Shell/Console feature if SPICE is used.
The CA certificate and key are stored in the Proxmox Cluster File System (pmxcfs).
Certificates for API and web GUI
The REST API and web GUI are provided by the pveproxy service, which runs on each node.
You have the following options for the certificate used by pveproxy:
By default the node-specific certificate in /etc/pve/nodes/NODENAME/pve-ssl.pem is used. This certificate is signed by the cluster CA and therefore not trusted by browsers and operating systems by default.
use an externally provided certificate (e.g. signed by a commercial CA).
use ACME (e.g., Let’s Encrypt) to get a trusted certificate with automatic renewal.
For options 2 and 3 the file /etc/pve/local/pveproxy-ssl.pem (and /etc/pve/local/pveproxy-ssl.key, which needs to be without password) is used.
Certificates are managed with the Proxmox VE Node management command (see the pvenode(1) manpage).
|Do not replace or manually modify the automatically generated node certificate files in /etc/pve/local/pve-ssl.pem and /etc/pve/local/pve-ssl.key or the cluster CA files in /etc/pve/pve-root-ca.pem and /etc/pve/priv/pve-root-ca.key.|
Getting trusted certificates via ACME
Proxmox VE includes an implementation of the Automatic Certificate Management Environment ACME protocol, allowing Proxmox VE admins to interface with Let’s Encrypt for easy setup of trusted TLS certificates which are accepted out of the box on most modern operating systems and browsers.
Currently the two ACME endpoints implemented are Let’s Encrypt (LE) and its staging environment (see https://letsencrypt.org), both using the standalone HTTP challenge.
Because of rate-limits you should use LE staging for experiments.
There are a few prerequisites to use Let’s Encrypt:
Port 80 of the node needs to be reachable from the internet.
There must be no other listener on port 80.
The requested (sub)domain needs to resolve to a public IP of the Node.
You have to accept the ToS of Let’s Encrypt.
At the moment the GUI uses only the default ACME account.
root@proxmox:~# pvenode acme account register default firstname.lastname@example.org Directory endpoints: 0) Let's Encrypt V2 (https://acme-v02.api.letsencrypt.org/directory) 1) Let's Encrypt V2 Staging (https://acme-staging-v02.api.letsencrypt.org/directory) 2) Custom Enter selection: 1 Attempting to fetch Terms of Service from 'https://acme-staging-v02.api.letsencrypt.org/directory'.. Terms of Service: https://letsencrypt.org/documents/LE-SA-v1.2-November-15-2017.pdf Do you agree to the above terms? [y|N]y Attempting to register account with 'https://acme-staging-v02.api.letsencrypt.org/directory'.. Generating ACME account key.. Registering ACME account.. Registration successful, account URL: 'https://acme-staging-v02.api.letsencrypt.org/acme/acct/xxxxxxx' Task OK root@proxmox:~# pvenode acme account list default root@proxmox:~# pvenode config set --acme domains=example.invalid root@proxmox:~# pvenode acme cert order Loading ACME account details Placing ACME order Order URL: https://acme-staging-v02.api.letsencrypt.org/acme/order/xxxxxxxxxxxxxx Getting authorization details from 'https://acme-staging-v02.api.letsencrypt.org/acme/authz/xxxxxxxxxxxxxxxxxxxxx-xxxxxxxxxxxxx-xxxxxxx' ... pending! Setting up webserver Triggering validation Sleeping for 5 seconds Status is 'valid'! All domains validated! Creating CSR Finalizing order Checking order status valid! Downloading certificate Setting pveproxy certificate and key Restarting pveproxy Task OK
Switching from the staging to the regular ACME directory
Changing the ACME directory for an account is unsupported. If you want to switch an account from the staging ACME directory to the regular, trusted, one you need to deactivate it and recreate it.
This procedure is also needed to change the default ACME account used in the GUI.
root@proxmox:~# pvenode acme account info default Directory URL: https://acme-staging-v02.api.letsencrypt.org/directory Account URL: https://acme-staging-v02.api.letsencrypt.org/acme/acct/6332194 Terms Of Service: https://letsencrypt.org/documents/LE-SA-v1.2-November-15-2017.pdf Account information: ID: xxxxxxx Contact: - mailto:email@example.com Creation date: 2018-07-31T08:41:44.54196435Z Initial IP: 192.0.2.1 Status: valid root@proxmox:~# pvenode acme account deactivate default Renaming account file from '/etc/pve/priv/acme/default' to '/etc/pve/priv/acme/_deactivated_default_4' Task OK root@proxmox:~# pvenode acme account register default firstname.lastname@example.org Directory endpoints: 0) Let's Encrypt V2 (https://acme-v02.api.letsencrypt.org/directory) 1) Let's Encrypt V2 Staging (https://acme-staging-v02.api.letsencrypt.org/directory) 2) Custom Enter selection: 0 Attempting to fetch Terms of Service from 'https://acme-v02.api.letsencrypt.org/directory'.. Terms of Service: https://letsencrypt.org/documents/LE-SA-v1.2-November-15-2017.pdf Do you agree to the above terms? [y|N]y Attempting to register account with 'https://acme-v02.api.letsencrypt.org/directory'.. Generating ACME account key.. Registering ACME account.. Registration successful, account URL: 'https://acme-v02.api.letsencrypt.org/acme/acct/39335247' Task OK
Automatic renewal of ACME certificates
If a node has been successfully configured with an ACME-provided certificate (either via pvenode or via the GUI), the certificate will be automatically renewed by the pve-daily-update.service. Currently, renewal will be attempted if the certificate has expired or will expire in the next 30 days.