Change NTP client to systemd-timesyncd.

(Excluding our NTP master.)  It's simpler, arguably more secure, and
provides enough functionality when only simple client use-cases are
desired.

We allow outgoing connections to 123/udp also on NTP slaves so systemd-timesyncd
can connect to the fallbacks NTP servers.

3 files changed, 15 insertions, 14 deletions

diff --git a/roles/common/templates/etc/nftables.conf.j2 b/roles/common/templates/etc/nftables.conf.j2
index c89a136..808383c 100755
--- a/roles/common/templates/etc/nftables.conf.j2
+++ b/roles/common/templates/etc/nftables.conf.j2
@@ -168,7 +168,9 @@ table inet filter {
         # incoming ICMP/ICMPv6 traffic was filtered in the ingress chain already
         meta l4proto { icmp, icmpv6 } counter accept
 
-        udp sport  123 udp dport  123 ct state     related,established accept
+        # NTP (ntpd uses sport 123 but systemd-timesyncd does not)
+        udp sport 123 ct state related,established accept
+
 {% if groups.all | length > 1 %}
         udp sport  500 udp dport  500 ct state new,related,established accept
 {% if groups.NATed | length > 0 %}
@@ -206,7 +208,9 @@ table inet filter {
 
         meta l4proto { icmp, icmpv6 } counter accept
 
-        udp sport  123 udp dport  123 ct state new,related,established accept
+        # NTP (ntpd uses sport 123 but systemd-timesyncd does not)
+        udp dport 123 ct state new,related,established accept
+
 {% if groups.all | length > 1 %}
         udp sport  500 udp dport  500 ct state new,related,established accept
 {% if groups.NATed | length > 0 %}
diff --git a/roles/common/templates/etc/ntp.conf.j2 b/roles/common/templates/etc/ntp.conf.j2
index 1016d55..b76f0dd 100644
--- a/roles/common/templates/etc/ntp.conf.j2
+++ b/roles/common/templates/etc/ntp.conf.j2
@@ -15,7 +15,6 @@ filegen clockstats file clockstats type day enable
 
 
 # You do need to talk to an NTP server or two (or three).
-{% if 'NTP_master' in group_names %}
 # Use Stratum One Time Servers:
 # http://support.ntp.org/bin/view/Servers/StratumOneTimeServers
 server sth1.ntp.se iburst
@@ -24,17 +23,6 @@ server gbg1.ntp.se iburst
 server gbg2.ntp.se iburst
 server ntp1.sp.se  iburst
 server ntp2.sp.se  iburst
-{% else %}
-# Sychronize to our (stratum 2) NTP server, to ensure our network has a
-# consistent time.
-{% for host in groups['NTP_master'] | sort %}
-server {{ ipsec[ hostvars[host].inventory_hostname_short ] }} prefer iburst
-{% endfor %}
-pool 0.{{ geoip | default('debian') }}.pool.ntp.org iburst
-pool 1.{{ geoip | default('debian') }}.pool.ntp.org iburst
-pool 2.{{ geoip | default('debian') }}.pool.ntp.org iburst
-pool 3.{{ geoip | default('debian') }}.pool.ntp.org iburst
-{% endif %}
 
 
 # Access control configuration; see /usr/share/doc/ntp-doc/html/accopt.html for
diff --git a/roles/common/templates/etc/systemd/timesyncd.conf.d/fripost.conf.j2 b/roles/common/templates/etc/systemd/timesyncd.conf.d/fripost.conf.j2
new file mode 100644
index 0000000..f578cd9
--- /dev/null
+++ b/roles/common/templates/etc/systemd/timesyncd.conf.d/fripost.conf.j2
@@ -0,0 +1,9 @@
+[Time]
+# Sychronize to our (stratum 2) NTP server, to ensure our network has a
+# consistent time.
+{%- set ntp = [] -%}
+{%- for host in groups['NTP_master'] -%}
+{%- set _ = ntp.append(ipsec[ hostvars[host].inventory_hostname_short ]) -%}
+{%- endfor %}
+
+NTP={{ ntp | join(' ') }}