diff --git a/rootfs-builder/rootfs.sh b/rootfs-builder/rootfs.sh
index 653276e1b..8568d7b8c 100755
--- a/rootfs-builder/rootfs.sh
+++ b/rootfs-builder/rootfs.sh
@@ -368,6 +368,14 @@ popd  >> /dev/null
 
 [ -n "${KERNEL_MODULES_DIR}" ] && copy_kernel_modules ${KERNEL_MODULES_DIR} ${ROOTFS_DIR}
 
+chrony_conf_file="${ROOTFS_DIR}/etc/chrony.conf"
+if [ ${distro} == ubuntu ] || [ ${distro} == debian ] ; then
+	chrony_conf_file="${ROOTFS_DIR}/etc/chrony/chrony.conf"
+fi 
+
+info "Configure chrony file ${chrony_conf_file}"
+echo "refclock PHC /dev/ptp0 poll 3 dpoll -2 offset 0" >> ${chrony_conf_file}
+
 # The CC on s390x for fedora needs to be manually set to gcc when the golang is downloaded from the main page.
 # See issue: https://github.com/kata-containers/osbuilder/issues/217
 [ "$distro" == fedora ] && [ "$ARCH" == "s390x" ] && export CC=gcc