thinQmaster Virtual testing partner Adaptive practice exams that find your weak spots and drill them. Every answer explained. From $69
Enroll

thinQmaster

Find your exam

Five questions free, before you decide.

Step 1 · choose a vendor

In one of our camps? Your practice exams come with the tuition — they are on your study page already.

Networking Fundamentals · Foundational

Interface Errors

Counters on network interfaces that track problems such as CRC errors, runts, giants, collisions, drops and discards.

Definition

Input errors usually point to physical issues, output drops to congestion, and late collisions to duplex problems. Monitoring tools poll these counters via SNMP to spot degrading links. Counters should be cleared and rechecked to confirm whether errors are still increasing.

Example

show interfaces counters errors on a Cisco switch lists per-port error totals.

Exam tip

Errors indicate physical or configuration faults; discards and output drops usually indicate congestion.

Related terms