Question

A network administrator wants router R2 to synchronize its clock with a central time source at 10.1.1.10 so that log timestamps across all devices are consistent. The administrator enters the command 'ntp server 10.1.1.10' on R2. After a few minutes, 'show ntp associations' shows the server address but the entry is not marked as synchronized, and 'show ntp status' reports the clock as unsynchronized. Assuming IP connectivity to 10.1.1.10 is confirmed, which condition would MOST likely prevent R2 from synchronizing?

Accepted Answer

The time source at 10.1.1.10 has a stratum value of 16, so it is considered unsynchronized and unusable as a reference.

Answer

R2 requires the 'ntp master' command before it can act as an NTP client to a remote server.

Answer

NTP uses TCP port 123, and the three-way handshake to the server has not yet completed.

Answer

R2 must have 'ntp peer 10.1.1.10' configured instead, because 'ntp server' only works between two routers of equal stratum.