sonic-buildimage/files/image_config/ntp/ntp.conf.j2

###############################################################################
# Managed by Ansible
# file: ansible/roles/acs/templates/ntp.conf.j2
###############################################################################

# /etc/ntpsec/ntp.conf, configuration for ntpd; see ntp.conf(5) for help

# To avoid ntpd from panic and exit if the drift between new time and
# current system time is large.
tinker panic 0

driftfile /var/lib/ntpsec/ntp.drift
leapfile /usr/share/zoneinfo/leap-seconds.list

# To enable Network Time Security support as a server, obtain a certificate
# (e.g. with Let's Encrypt), configure the paths below, and uncomment:
# nts cert CERT_FILE
# nts key KEY_FILE
# nts enable

# You must create /var/log/ntpsec (owned by ntpsec:ntpsec) to enable logging.
#statsdir /var/log/ntpsec/
#statistics loopstats peerstats clockstats
#filegen loopstats file loopstats type day enable
#filegen peerstats file peerstats type day enable
#filegen clockstats file clockstats type day enable

# Specify one or more NTP servers.

# Public NTP servers supporting Network Time Security:
# server time.cloudflare.com nts
{% for ntp_server in NTP_SERVER %}
server {{ ntp_server }} iburst
{% endfor %}

# pool.ntp.org maps to about 1000 low-stratum NTP servers.  Your server will
# pick a different set every time it starts up.  Please consider joining the
# pool: <https://www.pool.ntp.org/join.html>

#listen on source interface if configured, else 
#only listen on MGMT_INTERFACE, LOOPBACK_INTERFACE ip when MGMT_INTERFACE is not defined, or eth0 
# if we don't have both of them (default is to listen on all ip addresses)
interface ignore wildcard
{%- macro check_ip_on_interface(interface_name, table_name) %}
    {%- set ns = namespace(valid_intf = 'false') %}
    {%- if table_name %}
        {%- for (name, source_prefix) in table_name|pfx_filter %}
            {%- if source_prefix and name == interface_name %}
                {%- set ns.valid_intf = 'true' %}
            {%- endif %}
        {%- endfor %}
    {%- endif %}
{{ ns.valid_intf }}
{%- endmacro %}

{% set ns = namespace(source_intf = "") %}
{%- set ns = namespace(source_intf_ip = 'false') %}
{%- if (NTP) and (NTP['global']['src_intf'])  %}
    {%- set ns.source_intf = (NTP['global']['src_intf']) %}
    {%- if ns.source_intf != "" %}
        {%- if ns.source_intf == "eth0" %}
            {%- set ns.source_intf_ip = 'true' %}
        {%- elif ns.source_intf.startswith('Vlan') %}
            {%- set ns.source_intf_ip = check_ip_on_interface(ns.source_intf, VLAN_INTERFACE) %}
        {%- elif ns.source_intf.startswith('Ethernet') %}
            {%- set ns.source_intf_ip = check_ip_on_interface(ns.source_intf, INTERFACE) %}
        {%- elif ns.source_intf.startswith('PortChannel') %}
            {%- set ns.source_intf_ip = check_ip_on_interface(ns.source_intf, PORTCHANNEL_INTERFACE) %}
        {%- elif ns.source_intf.startswith('Loopback') %}
            {%- set ns.source_intf_ip = check_ip_on_interface(ns.source_intf, LOOPBACK_INTERFACE) %}
        {%- endif %}
    {%- endif %}
{% endif %}

{% if ns.source_intf_ip == 'true' %}
interface listen {{ns.source_intf}}
{% elif (NTP) and NTP['global']['vrf'] == 'mgmt' %}
interface listen eth0
{% elif MGMT_INTERFACE %}
{% for (mgmt_intf, mgmt_prefix) in MGMT_INTERFACE|pfx_filter %}
interface listen {{ mgmt_prefix | ip }}
{% endfor %}
{% elif LOOPBACK_INTERFACE %}
{% for (name, prefix) in LOOPBACK_INTERFACE|pfx_filter %}
{% if prefix | ipv4 and name == 'Loopback0' %}
interface listen {{ prefix | ip }}
{% endif %}
{% endfor %}
{% else %}
interface listen eth0
{% endif %}
interface listen 127.0.0.1

# Access control configuration; see /usr/share/doc/ntpsec-doc/html/accopt.html
# for details.
#
# Note that "restrict" applies to both servers and clients, so a configuration
# that might be intended to block requests from certain clients could also end
# up blocking replies from your own upstream servers.

# By default, exchange time with everybody, but don't allow configuration.
# NTPsec doesn't establish peer associations, and so nopeer has no effect, and has been removed from here
restrict default kod nomodify noquery limited

# Local users may interrogate the ntp server more closely.
restrict 127.0.0.1
restrict ::1