OPNsense Forum

English Forums => General Discussion => Topic started by: mb19 on July 21, 2025, 11:05:56 AM

Title: OPNsense NTP Not Syncing — Servers Reach 0, ntpdate fails
Post by: mb19 on July 21, 2025, 11:05:56 AM
Hi everyone,

I'm running into an issue where my OPNsense firewall isn't synchronizing time via NTP, and I can't figure out why.

1. My setup:
- OPNsense version:  25.1.11
- Outbound firewall rules allow UDP/123.
- WAN and LAN traffic is visible for NTP in packet captures.
- DNS works fine and NTP server IPs resolve correctly.

From the shell, I can ping NTP servers:

PING 92.113.12.77 (92.113.12.77): 56 data bytes
64 bytes from 92.113.12.77: icmp_seq=0 ttl=56 time=17.904 ms
64 bytes from 92.113.12.77: icmp_seq=1 ttl=56 time=18.382 ms
--- 92.113.12.77 ping statistics ---
2 packets transmitted, 2 packets received, 0.0% packet loss

2. DNS resolution works:

host 0.opnsense.pool.ntp.org

0.opnsense.pool.ntp.org has address 195.95.153.59
0.opnsense.pool.ntp.org has address 212.227.232.46
0.opnsense.pool.ntp.org has address 162.159.200.123
0.opnsense.pool.ntp.org has address 185.134.42.7


3. But ntpdate fails with:

ntpdate -u 92.113.12.77
no server suitable for synchronization found

4. ntpq -pn shows all servers stuck in .INIT. state:

     remote           refid      st t when poll reach   delay   offset  jitter
==============================================================================
 92.113.12.77    .INIT.          16 u    -  256    0    0.000   +0.000   0.000
 130.206.3.166   .INIT.          16 u    -  256    0    0.000   +0.000   0.000

5. Packet captures on igb0 (LAN) and WAN interfaces show NTP requests and responses coming back from the server, e.g.:

192.168.10.2.58914 > 178.255.228.77.123: NTPv4, Client, length 48
178.255.228.77.123 > 192.168.10.2.58914: NTPv4, Server, length 48

Even though packets are flowing in both directions, OPNsense never syncs time. All NTP servers remain in unreachable (reach = 0) state.

I've already:

- Restarted the NTP daemon (service ntpd restart)
- Tried ntpdate -b, -u, -t, etc.
- Different NTP servers (using their IP addresses directly in case it was a DNS issue)
- Contacted my ISP to ask whether they might be blocking NTP traffic, but I'm still waiting for a response

What else could I check or try? Any help would be greatly appreciated!

I'm still fairly new to all of this, so it's entirely possible I've missed something or misconfigured a step along the way while trying to troubleshoot.

Title: Re: OPNsense NTP Not Syncing — Servers Reach 0, ntpdate fails
Post by: Patrick M. Hausen on July 21, 2025, 11:52:28 AM
The pool addresses and the two servers in your other output do not match. Are you sure you are trying to use public servers?
Title: Re: OPNsense NTP Not Syncing — Servers Reach 0, ntpdate fails
Post by: mb19 on July 21, 2025, 12:22:26 PM
Oh you are right, sorry, the post and the examples are a bit confusing.

I've simplified everything now.

With this IP --> 178.215.228.24, which is from 0.es.pool.ntp.org, these are the results:


--> ntpq -pn

 remote           refid      st t when poll reach   delay   offset  jitter
==============================================================================
 178.215.228.24  .INIT.          16 u    -   64    0    0.000   +0.000   0.000

--> ping 0.es.pool.ntp.org
PING 0.es.pool.ntp.org (178.215.228.24): 56 data bytes
64 bytes from 178.215.228.24: icmp_seq=0 ttl=53 time=33.199 ms
64 bytes from 178.215.228.24: icmp_seq=1 ttl=53 time=33.755 ms



Title: Re: OPNsense NTP Not Syncing — Servers Reach 0, ntpdate fails
Post by: pfry on July 21, 2025, 05:42:07 PM
Are there any filters upstream (toward the Internet) of your OPNsense machine? Can you sync machines connected in parallel to (if feasible) or through your OPNsense machine?