What does unknown protocol drops mean?

Unknown protocol drops reports the packets with unknown or un-configured protocol on a per interface basis. Therefore it can be any protocol that the router doesn’t recognize.

What is protocol down on a Cisco router?

The line protocol being down indicates a clocking or framing problem. Probable reasons for this are encapsulation and clock rate mismatches. Ethernet0 is administratively down, line protocol is down: This output indicates that a local interface has been manually shut down using the shutdown command.

What is an interface reset on a Cisco switch?

If the system notices that the carrier detect line of a serial interface is up, but the line protocol is down, it periodically resets the interface in an effort to restart it. Interface resets can also occur when an interface is looped back or shut down.”

What does clear counters command do?

Counters on a device usually increase over time and can mask potential problems if left to accumulate. The clear counters command clears all interface counters on the device. Rules can be defined to automate this operation using the clearCounters action.

What causes input errors on Cisco router?

Input error: Includes runts, giants, no buffer, CRC, frame, overrun, and ignored counts. Other input-related errors can also cause the input error count to be increased, and some datagrams may have more than one error; therefore, this sum may not balance with the sum of enumerated input error counts.

What are unknown protocol drops?

03-03-2011 11:15 PM 03-03-2011 11:15 PM Unknown protocol drops reports the packets with unknown or un-configured protocol on a per interface basis. Therefore it can be any protocol that the router doesn’t recognize. And it is possible you’re receiving protocols you don’t have configured – IPX, Appletalk, IPv6, some other.

Can throttling cause unknown protocol drops?

I believe that it is very unlikely that the unknown protocol drops are due to throttling on the host side. If the output were from a router interface my first guess would be that it was frames for DTP from a connected switch that was causing the unknown protocol drops (this is a fairly common issue).

Does the router drop all packets received with IP options?

The router drops all the packets received with IP options. Note To resume normal options processing, use the no form of the command: no ip options 26-4 Cisco 10000 Series Router Software Configuration Guide

Why can’t I receive certain protocols on my router?

Therefore it can be any protocol that the router doesn’t recognize. And it is possible you’re receiving protocols you don’t have configured – IPX, Appletalk, IPv6, some other. I would suggest you to put a sniffer on the line, it will show you everything passing through the nic.