Precision Time Synchronization for Industrial Networks
Configure NTP on 5000 Series Switches with Reliable Accuracy

In modern industrial networks, accurate time synchronization is essential for ensuring reliable communication, event correlation, and system stability. Protocols such as NTP (Network Time Protocol) play a critical role in aligning timestamps across devices, especially in environments like SCADA systems, industrial automation, and IoT deployments.

This guide provides a step-by-step walkthrough on how to configure NTP on the 5000 Series switches via CLI, helping you establish a stable and synchronized network time foundation for your industrial infrastructure.

1. Accessing the CLI

1.1 Serial Console Access

  1. Connect to the serial port
    • Default baud rate: 9600
  2. Log in to the switch
    • Username: admin
    • Password: admin

Note: After entering the username, wait about 1 second until the Password: prompt appears before typing the password.

  1. After login, press Enter.
    When you see the prompt:

    Switch#

    it indicates that you have successfully entered the CLI.

1.2 Telnet Access

Use a terminal tool (e.g., MobaXterm) to connect via Telnet using the switch IP address.

1.3 Enter Configuration Mode

enable
config
  • enable: Enter privileged mode
  • config: Enter configuration mode

2. Configuring Date and Time

Set the system date and time manually:

date

Follow the prompts to input:

  • Date (yyyy-mm-dd)
  • Time (hh:mm:ss)

Then save the configuration:

write

3. Configure the Switch as an NTP Master

Set the switch as the NTP time source:

ntp master primary

Verify NTP status:

show ntp status

Key Output Fields

ParameterDescription
Clock StatusSynchronization status
Clock StratumTime hierarchy level
Reference IDTime source (e.g., LOCL)
Clock OffsetTime deviation
Root DelayNetwork delay

4. Configure NTP Client Synchronization

On a client switch:

  1. Enter configuration mode (same as Section 1)
  2. Configure NTP server: 
ntp server 192.168.0.28
  1. Verify synchronization status: 
show ntp status

Note: NTP synchronization may take 2–60 seconds to take effect.

  1. Save configuration: 
write

5. Configure NTP Query Interval

View available NTP options:

ntp ?

Set synchronization interval (in seconds):

ntp query-interval 60

Verify:

show ntp status

Recommendation

  • Industrial environments: ≥ 60 seconds
  • Typical range: 60–300 seconds

6. Overview of NTP Configuration Options

1️⃣ master — Act as NTP Master (Critical)

ntp master

Description:
Makes the switch act as a local time source (Stratum 1 or user-defined).

Use Cases:

ScenarioRecommendation
No external time source✅ Recommended
With Windows NTP Server❌ Not recommended
Offline industrial systems✅ Common

Risks:

  • Time drift (similar to a PC clock)
  • Not a true standard time source

2️⃣ query-interval — Synchronization Interval

Description:
Defines how often the device queries the NTP server (in seconds).

Recommended:
60–300 seconds (industrial best practice)

3️⃣ server — NTP Server (Core Setting)

ntp server <IP>

Description:
Specifies the upstream time source.

Typical Use Case:

ntp server 192.168.x.x   # Windows NTP Server

👉 This is the most important configuration in most deployments.

4️⃣ stratum — Time Hierarchy (Advanced)

Description:
Defines the time level of the device.

LevelMeaning
1Primary (GPS / atomic clock)
2Synced from Stratum 1
3Lower levels

Note: Only meaningful when operating in master mode.

5️⃣ peer — Peer Synchronization (Advanced)

Description:
Allows two devices to synchronize with each other (no master/slave relationship).

Use Cases:

  • Dual-core switches
  • Redundant time systems

General Use:
❌ Typically not required in standard deployments

6️⃣ authentication — NTP Authentication (Security)

Description:
Prevents unauthorized or spoofed NTP servers.

Use Cases:

  • Power systems
  • Petrochemical industry
  • High-security environments

General Use:
❌ Optional for most standard projects

7️⃣ client — NTP Client Mode

Description:
Enables the device to synchronize with an external NTP server.

👉 Essentially makes the switch act as an NTP client.

8️⃣ max-distance — Maximum Allowed Offset (Advanced)

Description:
Defines the maximum acceptable time deviation before rejecting a time source.

👉 Helps avoid unreliable time synchronization.

Recommendation:
Keep default settings in most cases.

9️⃣ min-step — Minimum Adjustment Step (Advanced)

Description:
Defines the minimum time adjustment step.

Purpose:

  • Avoid frequent micro-adjustments
  • Control time correction behavior

Recommendation:
Use default settings unless fine-tuning is required.

✅ Summary (Best Practice for Industrial Networks)

  • Use a central NTP server (e.g., Windows Server)
  • Configure all switches as NTP clients
  • Set query-interval to ≥ 60 seconds
  • Avoid using master unless in isolated environments
  • Keep advanced parameters at default unless necessary
Avcomm 8000 Series – Third Generation
Building Stability While Accelerating Industrial Network Evolution