Re: [PATCH proxmox-backup 05/11] daily-update/docs: warn on excessive self-signed certificate lifetime

["Lukas Wagner" <l.wagner@proxmox.com>]

Just nit-picking here, but I think the daily-update part should be a
separate commit.

On Thu Jun 18, 2026 at 1:54 PM CEST, Shannon Sterz wrote:
> and document how to renew it. an excessive lifetime is reported when
> the lifetime of the certificate exceeds 3650 days (almost ten years),
> which corresponds to the default lifetime generated by
> proxmox-acme-api.
>
> Signed-off-by: Shannon Sterz <s.sterz@proxmox.com>
> ---
>  docs/certificate-management.rst | 31 +++++++++++++++++++++++++++++++
>  src/bin/proxmox-daily-update.rs |  4 ++++
>  2 files changed, 35 insertions(+)
>
> diff --git a/docs/certificate-management.rst b/docs/certificate-management.rst
> index 89f628049..722d8d88b 100644
> --- a/docs/certificate-management.rst
> +++ b/docs/certificate-management.rst
> @@ -333,3 +333,34 @@ Test your new certificate, using your browser.
>  
>  .. [1]
>     acme.sh https://github.com/acmesh-official/acme.sh
> +
> +Manually Renew Self-signed Certificates
> +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> +
> +Proxmox Backup Server creates and renews a self-signed certificate if no custom
> +or ACME certificate is provided. Older versions issued a certificate that was
> +valid for almost 1000 years and did not renew this certificate. Beginning with
> +version 4.2, new setups use shorter lived certificates that will be regularly

Should be 'shorter-lived' with a hyphen, I believe.

> +renewed. Old self-signed certificates are not replaced in order to not disrupt
> +existing backup setups. In such cases, the following line is logged:
> +
> +.. code-block:: console
> +
> +   Apr 04 12:17:51 pbs proxmox-daily-update[1170]: Self-signed certificate is valid for an excessive amount of time. Please renew it.
> +
> +To manually renew a certificate, navigate to Configuration -> Certificates.
> +Select the certificate ``proxy.pem``. Then click the "Delete Custom
> +Certificate" button. Alternatively, you can run the following command:
> +
> +.. code-block:: shell
> +
> +   proxmox-backup-manager cert update --force
> +
> +.. WARNING:: Any client using a fingerprint to verify TLS sessions with the
> +   server will need to be updated with the new fingerprint. This includes any
> +   Proxmox VE instance that may use it as a backup destination.
> +
> +After manually renewing the certificate once, Proxmox Backup Server will start
> +renewing the certificate itself. A certificate will be renewed at the earliest
> +15 days before it expires. Starting from 30 days before it expires,
> +notifications will be issued with a reminder about the upcoming renewal.
> diff --git a/src/bin/proxmox-daily-update.rs b/src/bin/proxmox-daily-update.rs
> index ffeb46e49..71fd653ce 100644
> --- a/src/bin/proxmox-daily-update.rs
> +++ b/src/bin/proxmox-daily-update.rs
> @@ -113,6 +113,10 @@ async fn renew_self_signed_certificate() -> Result<(), Error> {
>      } else if days <= 30 {
>          log::info!("Certificate expires within 30 days, notify about renewal.");
>          send_upcoming_self_signed_renewal_notification()?;
> +   } else if days > 365 * 10 {
> +        log::warn!(
> +            "Self-signed certificate is valid for an excessive amount of time. Please renew it."
> +        );
>      }
>  
>      Ok(())