Bug#1009856: chrony: Support refclock in /etc/chrony/sources.d

[Stephan Austermühle]

Package: chrony
Version: 4.0-8+deb11u2
Severity: important

Dear Maintainer,

please consider adding support for 'refclock' in /etc/chrony/sources.d.

Some compute providers (Azure, Hetzner, KVM) support PTP as a
high-precision alternative to NTP but that feature requires to
configure a refclock in chrony.

Example (works for Azure, Hetzner, and KVM):

refclock PHC /dev/ptp0 poll 2 dpoll -2 offset 0

Note that using PTP usually requires loading a corresponding Linux
kernel module, too (e.g., ptp_kvm).

-- System Information:
Debian Release: 11.3
APT prefers stable-updates
APT policy: (500, 'stable-updates'), (500, 'stable-security'), (500, 'stable')
Architecture: amd64 (x86_64)

Kernel: Linux 5.16.0-0.bpo.4-amd64 (SMP w/32 CPU threads; PREEMPT)
Kernel taint flags: TAINT_PROPRIETARY_MODULE, TAINT_OOT_MODULE, TAINT_UNSIGNED_MODULE
Locale: LANG=C.UTF-8, LC_CTYPE=C.UTF-8 (charmap=UTF-8), LANGUAGE not set
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)

Versions of packages chrony depends on:
ii adduser 3.118
ii init-system-helpers 1.60
ii iproute2 5.10.0-4
ii libc6 2.31-13+deb11u3
ii libcap2 1:2.44-1
ii libedit2 3.1-20191231-2+b1
ii libgnutls30 3.7.1-5
ii libnettle8 3.7.3-1
ii libseccomp2 2.5.1-1+deb11u1
ii tzdata 2021a-1+deb11u3
ii ucf 3.0043

chrony recommends no packages.

Versions of packages chrony suggests:
ii bind9-dnsutils [dnsutils] 1:9.16.27-1~deb11u1
ii dnsutils 1:9.16.27-1~deb11u1
pn networkd-dispatcher <none>

-- Configuration Files:
/etc/default/chrony changed:
DAEMON_OPTS="-F 1 -P 0"


-- no debconf information

[Vincent Blut]

Hi Stephan,

Le 2022-04-19 12:10, Stephan Austermühle a écrit :
> Package: chrony
> Version: 4.0-8+deb11u2
> Severity: important
>
> Dear Maintainer,
>
> please consider adding support for 'refclock' in /etc/chrony/sources.d.
>
> Some compute providers (Azure, Hetzner, KVM) support PTP as a
> high-precision alternative to NTP but that feature requires to
> configure a refclock in chrony.
>
> Example (works for Azure, Hetzner, and KVM):
>
> refclock PHC /dev/ptp0 poll 2 dpoll -2 offset 0
>
> Note that using PTP usually requires loading a corresponding Linux
> kernel module, too (e.g., ptp_kvm).

Please specify your hardware reference clock in /etc/chrony/chrony.conf.
Only NTP sources (i.e. sources declared by the peer, pool and server
directives) can be specified in /etc/chrony/sources.d.

Cheers,
Vincent