Cisco Show interface Command details

Router#show Interface E0/2

ETHERNET0/2 is up, line protocol are up

Hardware is Lance, address is 0019.e78a.6401 <bia 0019.e78a.6401>

Internet address is 1.1.1.9/24

MTU bytes, BW 10000 Kbit, DLY 1000usec,

Reliability 255/255, Txload 1/255, Rxload 1/255

Encapsulation ARPA, loopback not set

Keepalive Set <10 sec>

ARP Type:arpa, ARP Timeout 04:00:00

Last input 00:00:00, output 00:00:01, output hang never

Last clearing of "show interface" counters 00:03:35

Input queue:34/57/0/819 <size/max/drops/flushes); Total output drops:0

Queueing Strategy:fifo

Output QUEUE:0/40 <size/max>

5 minute input rate 7138000 bits/sec, 14870 packets/sec

5 minute output rate 0 bits/sec, 0 packets/sec

3109298 packets Input, 186557880 bytes, 0 no buffer

Received 217 broadcasts < 0 multicast>

0 runts, 0 giants, 0 throttles

0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored

1. Interface status

ETHERNET0/2 is up, line protocol are up

ETHERNET0/2 is up indicates that there is no problem with the physical interface, and line protocol was up indicates that there is no problem with the data link layer.

If an administrator takes the Shutdown command, the first field displays the information is administratively down.

If the router receives more than 5,000 errors within the active interval, the word Disable will appear in this field to show that the router automatically disables this port.

2. Interface Hardware address information

Hardware is Lance, address is 0019.e78a.6402 <bia 0019.e78a.6401>

Hardware using LANCE means: The router CPU uses the Local area Network Controller for Ethernet (LANCE)

The controller realizes the Ethernet interface data transmission. In other words, the interface is a 10M Ethernet interface.

There are many types of hardware, such as DEC21140 Fast Ethernet controller, AMDP2 Ethernet and Fast Ethernet

am79c971 Fast Ethernet device driver and so on, not listed here.

Address means the MAC addresses of the interface.

3. Interface Network Layer Address information

Internet address is 192.168.1.1/24

4.MTU

MTU bytes

The MTU is the maximum transmission unit of the interface, combined with the following encapsulation ARPA . Cisco packages under Ethernet default is Ethernetii, the maximum transmission unit is 1518 bytes, the minimum is not less than the bytes.

The MTU interface command can be used to change the default MTU, the minimum MTU is 64 bytes, and the maximum value is 65535 bytes.

5. Bandwidth

BW 10000 Kbit

The interface bandwidth (BW) usually refers to the operating rate of the interface, expressed in kilobytes per second. Because the Ethernet operation rate is 10Mbps, the BW value is displayed as 000Kb.

6. Delay

DLY usec

The delay of the interface, in subtle representations.

7. Reliability

Reliability 255/255

The reliability of the interface, expressed in 255/255. Reliability is calculated based on the power average of the CRC error rate within 5 minutes.

8. Load

Load 1/255

The load of the interface, expressed in 255/255. 1/255 means that the load at this point is almost 0. Note that the load value is dynamically changed, and the average load is calculated every 5 minutes.

9. Interface Encapsulation

Encapsulation ARPA

The Cisco package under Ethernet is ethernetii by default.

10. Loop settings

Loopback not set

Loop settings for testing use

11.keepalive message

keepalive set<10 sec>

The keepalive message is used to test whether the interface link is connected properly. We can see that the Keepalive message in the Ethernet network is sent every 10 seconds.

12.ARP protocol

ARP type:apra, ARP Timeout 04:00:00

In an IP environment, the ARP type is ARPA. You can change the encapsulation to HP PROBE or SNAP by using the ARP interface command.

The ARP protocol sets a timer that clears the associated ARP record when the timer expires, and CISCO defaults to 4 hours (14400S) for this timer, and of course everyone can modify it under the interface via the ARP Timeout command.

13. Final input and output

Last input 00:00:11, output 00:00:12, output Hang never

Represents the exact time at which the last packet was successfully received by the interface. This display is used to indicate when the interface has failed.

14. Last Cleanup

Last clearing of "show interface" counters never

Represents the time that an interface counter for measuring cumulative statistics was last reset to 0. The actual value shown for the last cleanup is based on the use of 32-bit MS counters. Displaying an asterisk indicates that the elapsed time is too long to be displayed, while the display 0:00:00 indicates that the counter is cleared before the 32 power Ms of the 2 31 power MS to 2. The last purge value on many routers will be expressed in days and months, or day and hour.

15. Queue Policy

Queueing Strategy:fifo

The default is first in, and Out (FIFO)

16. Queues

Input queue: 34/75/0/819 <size/max/drops/flushes>; totol Output drops:0

Output queue: 0/40 <size/max>

· Size: How many packets are in a queue

· Max: Maximum length of queue

· Drops: Number of drops due to queue full

· Flushes: Strategy for packet loss

Here we need to discuss the queue problem in and out of two directions. If it is out of direction always show that there is a packet in the queue that is very normal, indicating that there is a certain congestion in the direction. And if the packet is always shown in the direction of the queue, then the router does not have enough processing power to handle incoming packets. If packets that always show in the direction of the packet are constantly dropped, you may need to consider replacing the stronger router for the upgrade.

Rate in 17.5 minutes

5 minute input rate 7138000bit/sec, 14870 packets/sec

5 minute output rate 0bit/sec, 0packets/sec

Represents the average rate within 5 minutes.

If the interface is working in chaotic mode, read all the data frames in the network. This pattern is typically used to test data flowing through the network.

If the interface works in non-chaotic mode, only the data that is broadcast and posted directly to this interface is read.

18. Input packets and bytes

3109298 packets Input, 186557880 bytes, 0 no buffer

The first represents the total number of error-free packets received by the router. Second, it also represents the total number of bytes received by the router without an error packet.

19. Broadcasting

Received 217 Broadcast

0 runts, 0 giants, 0 throttles

Represents the total number of broadcast or multicast groupings received by the interface.

Runts: Error packets less than 64 bytes

Giants: Error packets larger than 1536 bytes

Throttles: The router perceives a buffer or processor overload and will switch off its receiver. If no buffer and throttles are always present, you may need to add memory.

You can use the clear counters command to clear the counters for an interface.

Router#clear counters s0/0

　

Cisco Show interface Command details