What causes Cisco output errors?

Output drops are caused by a congested interface. For example, the traffic rate on the outgoing interface cannot accept all packets that should be sent out. The ultimate solution to resolve the problem is to increase the line speed.

How do you know if an interface is reliable?

Reliability is calculated like this: reliability = number of packets / number of total frames. The value of 255 is the highest value meaning that the interface is very reliable at the moment. The calculation above is done every 5 minutes.

What are input errors on a Cisco interface?

Input error: Includes runts, giants, no buffer, CRC, frame, overrun, and ignored counts. Other input-related errors can also cause the input errors to 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 does Outdiscards mean?

The 450 user guide has this definition for outdiscards: outdiscards Count: This field displays how many outbound packets were discarded without errors that would have prevented their transmission. ( Some of these packets may have been discarded to increase buffer space.)

What causes interface resets on Cisco switch?

Interface resets Number of times an interface has been completely reset. This can happen if packets queued for transmission were not sent within several seconds. On a serial line, this can be caused by a malfunctioning modem that is not supplying the transmit clock signal, or by a cable problem.

How do I show port errors on a Cisco switch?

Use the show port command for CatOS or the show interface command for Cisco IOS to look for errdisable, disable or shutdown status. The show module command can indicate faulty, which can indicate a hardware problem.

What causes interface input errors?

There are many reasons the ProxySG interfaces may detect input errors. Some of these causes may be related to bad cables, defective interface on switch/router/sg, duplex mismatch, etc. To determine the root cause, it is important to try various simple troubleshooting actions such as the following: Swapping cables.

What causes errors on an interface?

Note: There are several potential sources of interface errors, including interface discards when there is insufficient bandwidth to support the traffic volume, misconfigured duplex and speed settings, excessive buffering on interfaces, misconfigured EtherChannels, and faulty cables or hardware.

What causes output discards?

Running port scanners and monitoring programs commonly cause discards because they send uncontrolled, bursty traffic. Frames/packets discarded because of CRC errors, runts, giants, and other errors are not included in the discard count. Packets dropped by the firewall do not increment discards.

Why do I get output drops on my Cisco Catalyst 3750?

Seeing output drops incrementing (not rapidly but steadily) on the Gig Eth Interfaces to which the Servers are connected. Is this merely a heavy traffic from/to the server causing the Switch to drop those packets or anything pertaining to the Server NIC which is causing the issue of delay for the Client Cisco Catalyst 3750

What kind of buffer does a 3750 switch have?

Its most likely the 3750 they have really low buffers and are renowned for total output drops incrementing , you don’t get it in the newer switches they increased the buffer from 6mb to 12mb on 3ks

Why do I keep dropping packets on my 3750?

As Mark as already noted, the 3750s are a bit infamous for dropping packets due to their small buffer resources. This is often most noticeable when 3750 QoS is enabled with its default settings. (NB: I have found, sometimes buffer tuning can mitigate most of the drops.

Is there a show counters command for Cisco Catalyst 6000?

The show counters [mod/port] command offers even more detailed statistics for ports and interfaces. This command is available for CatOS and the equivalent show counters interface card-type {slot/port} command was introduced in Cisco IOS software version 12.1(13)E for the Catalyst 6000 series only.