This article explains why the  show NTP commands do not display anything after committing the NTP configuration under the management routing instance, whereas it does display when it is configured on the default routing instance.

This is due to a feature limitation.  Read further to understand what needs to be done to resolve the issue.

Configuration Example

set system management-instance
set system ntp server 10.1.130.130 routing-instance mgmt_junos
set system ntp server 10.1.130.131 routing-instance mgmt_junos
set groups node0 interfaces fxp0 unit 0 family inet address 10.1.242.142/25   <-- fxp0 is the mgmt interface for SRX and routing devices, it is em0 for switching platforms.
set routing-options static route 0.0.0.0/0 next-hop 10.1.242.129
set routing-instances mgmt_junos routing-options static route 0.0.0.0/0 next-hop 10.1.242.129

In this example, the device can ping the NTP and DNS Server IP address. But DNS and NTP do not work.

{primary:node0}[edit]
root@jtac-lab# run show route table

mgmt_junos.inet.0: 3 destinations, 3 routes (3 active, 0 holddown, 0 hidden)
+ = Active Route, - = Last Active, * = Both

0.0.0.0/0          *[Static/5] 15:07:25
                    >  to 10.1.242.129 via fxp0.0
10.1.242.128/25   *[Direct/0] 15:07:26
                    >  via fxp0.0
10.1.242.142/32   *[Local/0] 15:07:26
                       Local via fxp0.0

{primary:node0}
root@jtac-lab> ping routing-instance mgmt_junos 10.1.130.130 rapid count 5
PING 10.1.130.130 (10.1.130.130): 56 data bytes
!!!!!
--- 10.1.130.130 ping statistics ---
5 packets transmitted, 5 packets received, 0% packet loss
round-trip min/avg/max/stddev = 0.398/2.657/11.248/4.296 ms

{primary:node0}
root@jtac-lab> ping routing-instance mgmt_junos 10.1.130.131 rapid count 5
PING 10.1.130.131 (10.1.130.131): 56 data bytes
!!!!!
--- 10.1.130.131 ping statistics ---
5 packets transmitted, 5 packets received, 0% packet loss
round-trip min/avg/max/stddev = 0.385/2.497/10.635/4.070 ms

{primary:node0}
root@jtac-lab> show ntp status no-resolve << There is no output here, which does not make sense.

{primary:node0}
root@jtac-lab> show ntp associations no-resolve  << There is no output here, which does not make sense.

{primary:node0}
root@jtac-lab> show system processes extensive | grep ntp
 2026 root           20    0 15432K  9952K select 0   0:03  0.00% ntpd

Note: Restarting ntpd-service too does not help.

Juniper devices that run Junos OS release 18.1R1 have the configuration support to use the management VRF for NTP. See Management Interface in a Nondefault Instance and ntp for more details. 

However, there is a limitation for this feature. You need to make sure that at least one interface exists and is up in the default routing instance.

Configure at least one interface and make sure it is up in the default routing instance to correct this problem.

Example

Configure lo0.0 with 127.0.0.1. Now you can see the NTP output correctly.

{primary:node0}[edit]
root@jtac-lab# show | compare
[edit interfaces lo0]
+    unit 0 {
+        family inet {
+            address 127.0.0.1/32;
+        }
+    }

{primary:node0}[edit]
root@jtac-lab# run show ntp associations no-resolve
   remote         refid           st t when poll reach   delay   offset  jitter
===============================================================================
*10.1.130.130    66.129.233.81    4 -   42   64    7    0.629   -0.336   0.248
+10.1.130.131    66.129.233.81    4 -   38   64    7    0.554    1.233   0.042

2021-08-30:  Article reviewed for accuracy; no changes required.
2020-05-12: Article modified to apply to all Junos and to describe issue with NTP configuration