Ten hands-on NTP labs — master/client/peer, authentication, stratum behavior, and time-sync verification — on CML free-tier (5 nodes or fewer).
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.
View lab detailsConfigure a Cisco IOS router as an authoritative NTP master at a chosen stratum and point a neighbor at it as a client. Understand how NTP stratum works and verify deterministically using show commands rather than waiting for live synchronization.
View lab detailsConfigure two Cisco IOS routers as symmetric-active NTP peers over a single /30 link. R1 is an authoritative clock (ntp master 4) and both routers form a symmetric peer relationship with ntp peer. Learn how peer mode differs from client/server, and how to verify and troubleshoot associations without relying on Internet sources.
View lab detailsNew here? Start with the free study hub and step-by-step guides, then own the bundle to practice on real Cisco IOS.
10 hands-on, auto-graded CCNA labs spanning 15 topics — each one a real Cisco Modeling Labs scenario you build on Cisco IOS. It's a one-time $29.99 and every lab is yours to keep forever.
A one-time purchase — $29.99. Buy once and own every lab in the bundle permanently; it's separate from the daily-lab subscription, so there's nothing recurring.
Yes — each lab is a Cisco Modeling Labs (CML) topology you import and build on real Cisco IOS, and the CML free tier is enough. You download the topology and lab guide, then build it yourself.
Every lab ships as a problem to solve. You build it in CML, then submit your config to grade it against the answer key — you get a pass/fail on each objective, so you know exactly what's right and what to fix instead of guessing.
CCNA. The labs are sequenced to build the hands-on configuration and troubleshooting skills CCNA candidates are expected to demonstrate on real gear.
Configure NTP MD5 authentication so a client (R2) synchronizes only to a trusted, authenticated master (R1). R1 is already an authoritative clock (ntp master 3). You will enable NTP authentication on both routers, define and trust key 1, and bind the key on R2's ntp server statement. Verification focuses on authenticated associations and status; actual time lock may take minutes and is not graded.
Configure a deterministic NTP broadcast design on a single shared LAN. R1 acts as an authoritative clock (ntp master 3) and broadcasts time on its LAN interface. R2 and R3 act as broadcast clients to scale time distribution without per-client server statements. Verify broadcast associations on the clients and understand the tradeoffs vs. unicast client/server.
View lab detailsConfigure a Cisco IOS router as an authoritative NTP master and restrict which clients it will serve using an NTP access-group with a standard ACL. One shared LAN (no routing) connects three routers through a Layer-2 switch. Only R2 is authorized to receive time from R1; R3 is denied. Learners deploy, verify, and troubleshoot the access-group behavior.
View lab detailsBuild a small LAN with two IOS routers acting as NTP masters at different strata and a client that lists both as time sources, preferring one using the prefer keyword. All routers share a single broadcast domain via a Layer-2 switch, with no routing configured. You will deploy deterministic NTP, verify associations, and understand redundancy selection behavior.
View lab detailsCreate a deterministic three-tier NTP hierarchy on a single shared LAN. R1 is the authoritative clock (ntp master 2), R2 syncs to R1, and R3 syncs to R2. No routing or additional subnets — all devices share 10.0.0.0/24 via one L2 switch. Verify with show ntp status and show ntp associations.
View lab detailsTwo-router /30 point-to-point lab. R1 is an authoritative UTC NTP master (stratum 3). Configure R2 as an NTP client to R1 and display local time in MST/MDT while remaining synchronized to UTC. Reinforces that NTP distributes UTC and the router applies timezone/daylight-saving only to presentation.
View lab detailsAdvanced NTP troubleshooting on a two-router /30. R2 never synchronizes its clock. Use show commands to diagnose, then correct the design intent so R2 deterministically references R1, and R1 is an authoritative time source at the agreed stratum. The starter ships with a pre-broken NTP configuration already applied; your job is to find and fix two independent faults.
View lab details