show interfaces
Table 16 | show interfaces | |
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Field |
| Description |
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CRC |
| Number of cyclic redundancy checksums generated by the originating LAN |
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| station or |
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| received. On a LAN, this usually indicates noise or transmission problems on the |
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| LAN interface or the LAN bus itself. A high number of CRCs is usually the |
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| result of collisions or a station transmitting bad data. |
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frame |
| Number of packets received incorrectly, having a CRC error and a noninteger |
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| number of octets. On a LAN, this is usually the result of collisions or a |
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| malfunctioning Ethernet device. |
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overrun |
| Number of times the receiver hardware was unable to hand received data to a |
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| hardware buffer because the input rate exceeded the receiver’s ability to handle |
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| the data. |
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ignored |
| Number of received packets ignored by the interface because the interface |
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| hardware ran low on internal buffers. These buffers are different from the system |
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| buffers mentioned previously in the buffer description. Broadcast storms and |
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| bursts of noise can cause the ignored count to be increased. |
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abort |
| Number of packets whose receipt was aborted. |
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packets output |
| Total number of messages transmitted by the system. |
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bytes |
| Total number of bytes, including data and MAC encapsulation, transmitted by |
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| the system. |
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underruns |
| Number of times the transmitter has been running faster than the router can |
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| handle. |
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output errors |
| Sum of all errors that prevented the final transmission of datagrams out of the |
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| interface being examined. Note that this may not balance with the sum of the |
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| enumerated output errors, as some datagrams might have more than one error, |
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| and others might have errors that do not fall into any of the specifically tabulated |
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| categories. |
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collisions |
| Number of messages retransmitted due to an Ethernet collision. This is usually |
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| the result of an overextended LAN (Ethernet or transceiver cable too long, more |
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| than two repeaters between stations, or too many cascaded multiport |
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| transceivers). A packet that collides is counted only once in output packets. |
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interface resets |
| Number of times an interface has been completely reset. This can happen if |
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| packets queued for transmission were not sent within several seconds. On a serial |
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| line, this can be caused by a malfunctioning modem that is not supplying the |
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| transmit clock signal, or by a cable problem. If the system notices that the carrier |
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| detect line of a serial interface is up, but the line protocol is down, it periodically |
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| resets the interface in an effort to restart it. Interface resets can also occur when |
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| an interface is looped back or shut down. |
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output buffer failures | Number of times the output buffer has failed. | |
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output buffers swapped out | Number of times the output buffer has been swapped out. | |
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