Goldfish Networks wordmark
BeginnerPublished 2026-07-04

CCNA NTP Client: Sync to an Authoritative Server

Free preview — the first lab of NTP & Network Time

Beginner CCNA NTP lab. Two IOS routers share a single /30 link with no routing. Configure R1 as an authoritative NTP master at stratum 3 and point R2 to R1 as its NTP server. Verify using show ntp associations, show ntp status, and show clock. Emphasis: deterministic config — grading checks the presence of ntp master 3 on R1 and ntp server 10.0.0.1 on R2, not live convergence.

Track
Est. time
25 minutes
Difficulty
Beginner
Topics

Learning objectives

  • Explain NTP roles: master (authoritative) vs. client and stratum behavior
  • Configure an IOS router as an authoritative NTP master using ntp master <stratum>
  • Configure an IOS router as an NTP client using ntp server <ip>
  • Verify NTP state with show ntp associations, show ntp status, and show clock
  • Recognize that NTP convergence takes minutes and grading is based on deterministic config

Troubleshooting focus

  • Interface down or wrong IP/mask prevents reachability to the NTP server
  • Missing ntp master on the server — clients have no valid source
  • Client points to the wrong IP (typo or different interface)
  • Clock appears unsynchronized because insufficient time has elapsed for NTP to settle

Topology

Lab topology diagram

Related labs

More hands-on Cisco Modeling Labs practice on the same track and topics.

Study this topic

Free guides, a command cheat sheet, and graded practice for this lab's topic.

Learn Network Services & Management

Grade your work

How this lab is graded
  • Build it your way. Where a lab lets you choose a value — a VLAN name, an interface description — grading checks that you configured it, not which name you picked. Names that another line has to reference, like an ACL applied with access-class, are stated in the guide and do have to match.
  • Addresses, modes and protocol keywords are exact. An IP address, a subnet mask, switchport mode trunk, an encapsulation — these carry the meaning of the lab, so they are graded as written in the guide.
  • Grading reads your saved configuration. Export the lab from CML after you have configured it, and make sure anything you set is in the running-config — a change that only exists in a terminal session never reaches the grader.
  • You can submit as many times as you like. Your best score stands, and each attempt tells you which checks passed so you can work the gaps.
  • Scored something you believe is correct? Use Report an issue on this page — that is exactly how the grading fixes in the changelog got found.

Create a free account to submit your lab for grading.

Create a free account
Found a problem with this lab?

Please sign in to report a problem — tying it to your attempts lets us reproduce and fix it faster.