Dear, To what is the increase of the field mentioned in the evidence sent.
show interface counter error
“Undersize”
Hello Jesus
The UnderSize column of the output shows the number of frames that are received that are smaller than the minimum allowed frame size of 64 bytes. Cisco describes it like so:
Description: CatOS sh port and Cisco IOS sh interfaces counters errors . The frames received that are smaller than the minimum IEEE 802.3 frame size of 64 bytes (which excludes framing bits, but includes FCS octets) that are otherwise well formed.
This can be caused by a duplex mismatch and physical problems, such as a bad cable, port, or NIC on the attached device. You will have to determine what is on the other end and attempt some troubleshooting by changing the physical connections. Also, if the other end of the Gi0/1 interface is a cisco device, implement the same command to take a look and see what potential errors are there.
I hope this has been helpful!
Laz