The em0 interface shows the input errors incrementing over the day. The goal of this article is to outline some of the reasons and possible ways to reduce/stop the errors.

Sometimes, it is observed that the error count increases for em0/fxp1 (control-link) interface. This happens when the control plane CPU is high. When these errors are seen, there is a high probability that the RE CPU is high.

Physical interface: em0, Enabled, Physical link is Up
Interface index: 8, SNMP ifIndex: 17, Generation: 3

Type: Ethernet, Link-level type: Ethernet, MTU: 1514, Clocking: Unspecified, Speed: 1000mbps
Device flags   : Present Running
Interface flags: SNMP-Traps
Link type      : Full-Duplex
Physical info  : Unspecified
Hold-times     : Up 0 ms, Down 0 ms
Current address: 02:00:00:02:00:04, Hardware address: 02:00:00:02:00:04
Alternate link address: Unspecified
Last flapped   : Never
Statistics last cleared: Never
Traffic statistics:
Input  bytes  :        1697097590654
Output bytes  :         111660495827
Input  packets:           2140172829
Output packets:           1314424430
IPv6 transit statistics:
Input  bytes  :                   0
Output bytes  :                   0
Input  packets:                   0
Output packets:                   0
Input errors:

Errors: 18, Drops: 0, Framing errors: 0, Runts: 0, Giants: 0, Policed discards: 0, Resource errors: 0

The next step is to bring down the CPU utilization. The following can be helpful to achieve this task:

1. Avoid unnecessary logging
2. Remove " count " option on the security policies
3. Deactivate all traceoptions and only activate when required for troubleshooting.