10 exam-style questions with answers and explanations, straight from our 1,030-question bank. Tap an answer to check yourself. When you're ready, take the scored version in the free practice test.
These 10 free C-212 questions are organized by exam domain, so you can see how each part of the Ethernet Communications 1 blueprint is tested. Reveal the answer and explanation under each question.
After a Cat 5e cable is reterminated, a basic continuity tester shows all eight pins connected to their matching pins, with no opens or shorts. Inspection finds that the conductors on pins 1 and 2 belong to different twisted pairs. How should this termination fault be classified?
Correct answer: C - A split pair: correct pin continuity with incorrect physical conductor pairing
A Layer 2 switch has aged the PLC's MAC address out of its forwarding table. A PC on port 1 now sends a unicast frame to that PLC. Ports 2, 3 and 4 are the only other forwarding ports in the same VLAN, and no security or flooding restrictions apply. What should appear on those three ports?
Correct answer: A - A copy of the frame on each port, still addressed to the PLC's unicast MAC
During a TCP transfer of a controller program, lost data is retransmitted. The receiving application eventually obtains the complete byte stream in order, but the transfer exceeds the specified 100 ms limit. How should this result be interpreted?
Correct answer: D - TCP recovered ordered delivery, but it does not guarantee the specified completion time.
Production must continue while a technician backs up a PLC containing online edits absent from the archived PC project. The manufacturer permits reading this controller's project in Run mode without interrupting execution. The read is authorized; no program write is authorized. Which operation preserves the current program under these conditions?
Correct answer: D - Read the running controller into a new PC project file and save it
A service laptop must communicate directly with a PLC at 10.44.6.40/23 through the same VLAN; no router is present. The address register lists that PLC and an HMI at 10.44.7.20/23 as the only assigned hosts. Which proposed laptop address is usable on this network?
Correct answer: D - 10.44.6.255/23
The DHCP service becomes unavailable during a shift. A controller's current lease still has three hours remaining; it has not restarted and continues exchanging data. No DHCPNAK or duplicate-address condition has occurred. What does DHCP require of this controller now?
Correct answer: B - Keep using the lease while attempting renewal as scheduled.
A technician changes only a Layer 2 switch's management IP address, moving it to another subnet. The laptop loses access to the web interface, while the connected PLC and HMI continue exchanging fresh data. What does this result establish?
Correct answer: A - Management reachability can fail while Layer 2 forwarding continues.
A main switch connects separately to the switches in Cells A and B. Each cell switch connects to its own PLC and HMI; all devices use one VLAN and IP subnet, with no alternate links. An engineering PC on the main switch reaches both Cell B devices but neither Cell A device. Cell A's HMI still displays changing values from its PLC. If one cable has failed, which cable fits every observation?
Correct answer: A - The uplink between Cell A and the main switch.
To capture a PLC-HMI exchange, an analyzer is connected to switch port 8. The PLC is on port 2, the HMI on port 3, and the uplink on port 1. Their requests and replies use learned unicast destinations within the same VLAN. Mirroring supports both directions, with sufficient capture capacity. Which setup captures both requests and replies?
Correct answer: B - Mirror both directions on port 2 to analyzer port 8.
A secured port on a Cisco IE 4010 receives traffic from a PLC and a visiting laptop through a downstream switch. The PLC's MAC is already configured as the port's sole secure address. Plant policy requires uninterrupted PLC traffic, rejection of unapproved sources, and recorded violations. Which configuration satisfies all three requirements?
Correct answer: C - Restrict mode at a secure-MAC maximum of one.
The full bank has 1,020 more C-212 questions with explanations.
Continue in the free practice test →
View plans