Purpose
By monitoring Fast Ethernet and Gigabit Ethernet interfaces, you begin to isolate Fast Ethernet and Gigabit Ethernet interface problems when they occur.
To monitor your Fast Ethernet and Gigabit Ethernet interfaces, follow these steps:
To display the status of Fast Ethernet or Gigabit Ethernet interfaces, use the following JUNOS command-line interface (CLI) operational mode command:
user@host> show interfaces terse fe* Interface Admin Link Proto Local Remote fe-2/1/0 up up fe-2/1/0.0 up up inet 10.116.115.217/29 fe-3/0/2 up down fe-3/0/2.0 up down fe-3/0/3 up up fe-3/0/3.0 up up inet 192.168.223.65/30 fe-4/1/0 down up fe-4/1/0.0 up down inet 10.150.59.133/30 fe-4/1/1 up up fe-4/1/1.0 up up inet 10.150.59.129/30 fe-4/1/2 up down fe-4/1/2.0 up down
Meaning
The sample output lists only the Fast Ethernet interfaces. It shows the status of both the physical and logical interfaces.
For a description of what the output means, see Table 40.
Table 40: Status of Fast Ethernet Interfaces
Sample Output
user@host> show interfaces
terse ge* Interface Admin Link Proto Local Remote ge-2/2/0 down down ge-2/2/0.0 up down inet 65.113.23.105/30 ge-2/3/0 up up ge-2/3/0.0 up up inet 65.115.56.57/30 ge-3/1/0 up up ge-3/1/0.0 up up inet 65.115.56.193/30 ge-3/2/0 up down
Meaning
This sample output lists only the Gigabit Ethernet interfaces. It shows the status of both the physical and logical interfaces. See Table 41 for a description of what the output means.
Table 41: Status of Gigabit Ethernet Interfaces
To display the status of a specific Fast Ethernet or Gigabit Ethernet interface when you need to investigate its status further, use the following JUNOS CLI operational mode command:
Sample Output 1
The following sample output is for a Fast Ethernet interface with the physical link up:
user@host> show interfaces fe-2/1/0
Physical interface: fe-2/1/0, Enabled, Physical link is Up
Interface index: 31, SNMP ifIndex: 35
Description: customer connection
Link-level type: Ethernet, MTU: 1514, Source filtering: Disabled
Speed: 100mbps, Loopback: Disabled, Flow control: Enabled
Device flags : Present Running
Interface flags: SNMP-Traps
Link flags : None
Current address: 00:90:69:86:71:1b, Hardware address: 00:90:69:86:71:1b
Input rate : 25768 bps (11 pps), Output rate: 1576 bps (3 pps)
Active alarms : None
Active defects : None
Logical interface fe-2/1/0.0 (Index 2) (SNMP ifIndex 43)
Flags: SNMP-Traps, Encapsulation: ENET2
Protocol inet, MTU: 1500, Flags: Is-Primary
Addresses, Flags: Is-Preferred Is-Primary
Destination: 10.116.151.218/29, Local: 10.119.115.217
Broadcast: 10.116.151.225
Sample Output 2
The following output is for a Gigabit Ethernet interface with the physical link up:
user@host> show interfaces ge-3/1/0
Physical interface: ge-3/1/0, Enabled, Physical link is Up
Interface index: 41, SNMP ifIndex: 55
Description: customer connection
Link-level type: Ethernet, MTU: 1514, Source filtering: Disabled
Speed: 1000mbps, Loopback: Disabled, Flow control: Enabled
Device flags : Present Running
Interface flags: SNMP-Traps
Link flags : None
Current address: 00:90:69:85:71:99, Hardware address: 00:90:69:85:71:99
Input rate : 7412216 bps (1614 pps), Output rate: 2431184 bps (1776 pps)
Active alarms : None
Active defects : None
Logical interface ge-3/1/0.0 (Index 11) (SNMP ifIndex 57)
Flags: SNMP-Traps, Encapsulation: ENET2
Protocol inet, MTU: 1500
Addresses, Flags: Is-Preferred Is-Primary
Destination: 10.117.65.192/30, Local: 10.115.65.193
Broadcast: 10.115.65.195
Meaning
The first line of sample output 1 and 2 shows that the physical link is up. This means that the physical link is healthy and can pass packets. Further down the sample output, look for active alarms and defects. If you see active alarms or defects, to further diagnose the problem, see Step 3, Display Extensive Status Information for a Specific Fast Ethernet or Gigabit Ethernet Interface, to display more extensive information about the Fast Ethernet interface and the physical interface that is down.
To display extensive status information about a specific Fast Ethernet or Gigabit Ethernet interface, use the following JUNOS CLI operational mode command:
Sample Output
The following sample output is for a Fast Ethernet interface:
user@router> show interfaces fe-1/3/3 extensive
Physical interface: fe-1/3/3, Enabled, Physical link is Up
Interface index: 47, SNMP ifIndex: 38
Description: Test
Link-level type: Ethernet, MTU: 1514, Source filtering: Disabled
Speed: 100mbps, Loopback: Disabled, Flow control: Enabled
Device flags : Present Running
Interface flags: SNMP-Traps
Link flags : None
Current address: 00:90:69:8d:2c:de, Hardware address: 00:90:69:8d:2c:de
Statistics last cleared: 2002-01-11 23:03:09 UTC (1w2d 23:54 ago)
Traffic statistics:
Input bytes : 373012658 0 bps
Output bytes : 153026154 1392 bps
Input packets: 1362858 0 pps
Output packets: 1642918 3 pps
Input errors:
Errors: 0 , Drops: 0, Framing errors: 0, Runts: 0, Policed discards: 503660
L3 incompletes: 1 , L2 channel errors: 0 , L2 mismatch timeouts: 0
FIFO errors: 0
Output errors:
Carrier transitions: 0, Errors: 0, Collisions: 0, Drops: 0, Aged packets: 0
HS link CRC errors: 0, FIFO errors: 0
Active alarms : None
Active defects : None
MAC statistics: Receive Transmit
Total octets 439703575 177452093
Total packets 1866532 1642916
Unicast packets 972137 1602563
Broadcast packets 30 2980
Multicast packets 894365 37373
CRC/Align errors 0 0
FIFO errors 0 0
MAC control frames 0 0
MAC pause frames 0 0
Oversized frames 0
Jabber frames 0
Fragment frames 0
VLAN tagged frames 0
Code violations 0
Filter statistics:
Input packet count 1866532
Input packet rejects 0
Input DA rejects 503674
Input SA rejects 0
Output packet count 1642916
Output packet pad count 0
Output packet error count 0
CAM destination filters: 5, CAM source filters: 0
Autonegotiation information:
Negotiation status: Complete, Link partner status: OK
Link partner: Full-duplex, Flow control: None
PFE configuration:
Destination slot: 1, Stream number: 15
CoS transmit queue bandwidth:
Queue0: 95, Queue1: 0, Queue2: 0, Queue3: 5
CoS weighted round-robin:
Queue0: 95, Queue1: 0, Queue2: 0, Queue3: 5
Logical interface fe-1/3/3.0 (Index 8) (SNMP ifIndex 69)
Description: Test
Flags: SNMP-Traps, Encapsulation: ENET2
Protocol inet, MTU: 1500, Flags: None
Addresses, Flags: Is-Preferred Is-Primary
Destination: 10.115.107.192/29, Local: 10.115.107.193
Broadcast: 10.115.107.199
Meaning
The sample output shows where the errors might be occurring and includes autonegotiation information. See Table 42 for a description of errors to look for.
Table 42: Errors to Look For
If the physical link is down, look at the active alarms and defects for the Fast Ethernet or Gigabit Ethernet interface and diagnose the Fast Ethernet or Gigabit Ethernet media accordingly. See Locate the Fast Ethernet and Gigabit Ethernet LINKAlarm and Counters for an explanation of Fast Ethernet and Gigabit Ethernet alarms.
Table 43 lists and describes some MAC statistics errors to look for.
Table 43: MAC Statistics Errors
Autonegotiation is the process that connected Ethernet interfaces use to communicate the information necessary to interoperate. Table 44 explains the autonegotiation information of the show interface interface-name extensive command output.
Table 44: Autonegotiation Information
To monitor statistics for a Fast Ethernet or Gigabit Ethernet interface, use the following JUNOS CLI operational mode command:
 |
Caution: We recommend that you use the monitor interface fe-fpc/pic/port or monitor interface ge-fpc/pic/port command only for diagnostic purposes. Do not leave these commands on during normal router operations because real-time monitoring of traffic consumes additional CPU and memory resources. |
Sample Output
The following sample output is for a Fast Ethernet interface:
user@host> monitor interface fe-2/1/0 Interface: fe-2/1/0, Enabled, Link is Up Encapsulation: Ethernet, Speed: 100mbps Traffic statistics: Current Delta Input bytes: 282556864218 (14208 bps) [40815] Output bytes: 42320313078 (384 bps) [890] Input packets: 739373897 (11 pps) [145] Output packets: 124798688 (1 pps) [14] Error statistics: Input errors: 0 [0] Input drops: 0 [0] Input framing errors: 0 [0] Policed discards: 6625892 [6] L3 incompletes: 75 [0] L2 channel errors: 0 [0] L2 mismatch timeouts: 0 [0] Carrier transitions: 1 [0] Output errors: 0 [0] Output drops: 0 [0] Aged packets: 0 [0] Active alarms : None Active defects: None Input MAC/Filter statistics: Unicast packets 464751787 [154] Packet error count 0 [0]
Meaning
Use the information from this command to help narrow down possible causes of an interface problem.
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Note: If you are accessing the router from the console connection, make sure you set the CLI terminal type using the set cli terminal command. |
The statistics in the second column are the cumulative statistics since the last time they were cleared using the clear interfaces statistics interface-name command. The statistics in the third column are the cumulative statistics since the monitor interface interface-name command was executed.
If the input errors are increasing, verify the following:
