-servers 0.openwrt.pool.ntp.org
-servers 1.openwrt.pool.ntp.org
-servers 2.openwrt.pool.ntp.org
-servers 3.openwrt.pool.ntp.org
+server 0.openwrt.pool.ntp.org
+server 1.openwrt.pool.ntp.org
+server 2.openwrt.pool.ntp.org
+server 3.openwrt.pool.ntp.org