diff --git a/phc2sys.service b/phc2sys.service
index 78ed68a..ff2f77e 100644
--- a/phc2sys.service
+++ b/phc2sys.service
@@ -1,6 +1,6 @@
 [Unit]
 Description=Synchronize system clock or PTP hardware clock (PHC)
-After=ntpdate.service
+After=ntpdate.service ptp4l.service
 
 [Service]
 Type=simple
diff --git a/ptp4l.service b/ptp4l.service
index 428394f..fbb26d1 100644
--- a/ptp4l.service
+++ b/ptp4l.service
@@ -1,5 +1,7 @@
 [Unit]
 Description=Precision Time Protocol (PTP) service
+After=network-online.target
+Wants=network-online.target
 
 [Service]
 Type=simple
diff --git a/timemaster.service b/timemaster.service
index 7505387..a6bda33 100644
--- a/timemaster.service
+++ b/timemaster.service
@@ -1,7 +1,8 @@
 [Unit]
 Description=Synchronize system clock to NTP and PTP time sources
-After=chronyd.service ntpd.service ntpdate.service sntp.service
+After=chronyd.service ntpd.service ntpdate.service sntp.service network-online.target
 Conflicts=chronyd.service ntpd.service phc2sys.service ptp4l.service
+Wants=network-online.target
 
 [Service]
 Type=simple