Monitoring SONET Interfaces
This section includes the following information to assist you when troubleshooting SONET interfaces:
Checklist for Monitoring SONET Interfaces
Purpose
To monitor SONET interfaces and begin the process of isolating SONET interface problems when they occur.
Action
Table 1 provides the links and commands for monitoring SONET interfaces.
Table 1: Checklist for Monitoring SONET Interfaces
Tasks | Command or Action |
---|---|
Monitoring SONET Interfaces | |
show interfaces terse so* | |
show interfaces so-fpc/pic/port | |
show interfaces so-fpc/pic/port extensive | |
monitor interface so-fpc/pic/port |
Monitoring SONET Interfaces
By monitoring SONET interfaces, you begin the process of isolating SONET interface problems when they occur.
To monitor your SONET interface, follow these steps:
Displaying the Status of SONET Interfaces
Purpose
To display the status of SONET interfaces, use the following Junos OS command-line interface (CLI) operational mode command:
Action
user@host> show interfaces terse so*
Meaning
The sample output lists only the SONET interfaces. It shows the status of both the physical and logical interfaces.
For a description of what the output means, see Table 2.
Table 2: Status of SONET Interfaces
Physical Interface | Logical Interface | Status Description |
---|---|---|
so-1/0/0 Admin Up Link Up | so-1/0/0.0 Admin Up Link Up | This interface has both the physical and logical links up and running. |
so-1/1/1 Admin Down Link Up | so-1/1/1.0 Admin Up Link Down | This interface is administratively disabled. The physical link is healthy (Link Up), but the logical link is not established end to end (Link Down). |
so-3/0/1 Admin Up Link Up | so-3/0/1.0 Admin Up Link Down | This interface is administratively enabled and the physical link is healthy (Link Up), but the logical interface is not established end to end (Link Down). |
so-5/3/0 Admin Up Link Down | so-5/3/0.0 Admin Up Link Down | This interface has the physical link down and the logical interface is down also. |
Displaying the Status of a Specific SONET Interface
Purpose
To display the status of a specific SONET interface when you need to investigate its status further, use the following Junos OS CLI operational mode command:
Action
user@host> show interfaces so-fpc/pic/port
Sample Output 1
user@router> show interfaces so-1/1/1 Physical interface: so-1/1/1, Enabled, Physical link is Down Interface index: 17, SNMP ifIndex: 16 Description: router-02 pos 4/0 Link-level type: Cisco-HDLC, MTU: 4474, Clocking: Internal, SONET mode Speed: OC3, Loopback: None, CRC: 32, Payload scrambler: Enabled Device flags : Present Running Down Interface flags: Hardware-Down Link-Layer-Down Point-To-Point SNMP-Traps Link flags : Keepalives Keepalive Input: 621 (00:02:57 ago), Output: 889 (00:00:09 ago) Input rate : 0 bps (0 pps), Output rate: 0 bps (0 pps) Active alarms : LOL, LOS Active defects : LOL, LOF, LOS, SEF, AIS-L, AIS-P, PLM-P Logical interface so-1/1/1.0 (Index 18) (SNMP ifIndex 30) Description: router-02 pos 4/0 Flags: Device-down Point-To-Point SNMP-Traps, Encapsulation: Cisco-HDLC Protocol inet, MTU: 4470 Addresses, Flags: Dest-route-down Is-Preferred Is-Primary Destination: 10.10.10.48/30, Local: 10.10.10.50 Protocol iso, MTU: 4469
Sample Output 2
The following output is for an interface with the physical layer up and the link layer down:
user@router> show interfaces so-3/0/1 Physical interface: so-3/0/1, Enabled, Physical link is Up Interface index: 28, SNMP ifIndex: 55 Description: Customer ABC Link-level type: Cisco-HDLC, MTU: 4474, Clocking: Internal, SONET mode, Speed: OC3, Loopback: None, FCS: 16, Payload scrambler: Enabled Device flags : Present Running Interface flags: Link-Layer-Down Point-To-Point SNMP-Traps Link flags : Keepalives Keepalive settings: Interval 10 seconds, Up-count 1, Down-count 3 Keepalive: Input: 113 (00:00:02 ago), Output: 119 (00:00:02 ago) Input rate : 80 bps (0 pps) Output rate : 88 bps (0 pps) SONET alarms : None SONET defects : None Logical interface so-3/0/1.0 (Index 22) (SNMP ifIndex 56) Flags: Device-Down Point-To-Point SNMP-Traps Encapsulation: Cisco-HDLC Protocol inet, MTU: 4470, Flags: None Addresses, Flags: Dest-route-down Is-Preferred Is-Primary Destination: 192.168.2.124/30, Local: 192.168.2.125
Meaning
In the first sample output, the first line of the sample output shows that the physical link is down. This means that the physical link is unhealthy and cannot pass packets. Further down the sample output, look for active alarms and defects. When you see this situation, to further diagnose the problem, see Displaying Extensive Status Information for a Specific SONET Interface to display more extensive information about the SONET interface and the physical interface that is down.
In the second sample output, the sample output shows that the link layer is down. This means that the logical interface is not established end to end. When you see this situation, to further diagnose the problem, see Monitoring Statistics for a SONET Interface to monitor statistics for the SONET interface and the logical interface that is down.
Displaying Extensive Status Information for a Specific SONET Interface
Purpose
To display extensive status information about a specific interface, use the following Junos OS CLI operational mode command:
Action
user@host> show interfaces so-fpc/pic/port extensive
Sample Output
user@router> show interfaces so-1/1/1 extensive
Physical interface: so-1/1/1, Enabled, Physical link is Down Interface index: 17, SNMP ifIndex: 16 Description: router-02 pos 4/0 Link-level type: Cisco-HDLC, MTU: 4474, Clocking: Internal, SONET mode Speed: OC3, Loopback: None, CRC: 32, Payload scrambler: Enabled Device flags : Present Running Down Interface flags: Hardware-Down Link-Layer-Down Point-To-Point SNMP-Traps Link flags : Keepalives Keepalive statistics: Input : 621 (last seen 00:05:35 ago) Output: 905 (last seen 00:00:07 ago) Statistics last cleared: Never Traffic statistics: Input bytes : 378736540 0 bps Output bytes : 6786356 0 bps Input packets: 225924 0 pps Output packets: 104798 0 pps Input errors: Errors: 8, Drops: 0, Framing errors: 4181286, Runts: 0, Giants: 8 Policed discards: 9474, L3 incompletes: 0, L2 channel errors: 0 L2 mismatch timeouts: 3, HS link CRC errors: 0, HS link FIFO overflows: 0 Output errors: Carrier transitions: 2, Errors: 0, Drops: 0, Aged packets: 0 HS link FIFO underflows: 0 Active alarms : LOL, LOS <-- SONET active alarms and defects Active defects : LOL, LOF, LOS, SEF, AIS-L, AIS-P, PLM-P SONET PHY: Seconds Count State <-- SONET media-specific errors PLL Lock 0 0 OK PHY Light 328 1 Light Missing SONET section: <-- SONET section errors BIP-B1 0 0 SEF 329 3 Defect Active LOS 329 2 Defect Active LOF 329 2 Defect Active ES-S 329 SES-S 329 SEFS-S 329 SONET line: BIP-B2 0 0 REI-L 0 0 RDI-L 0 0 OK AIS-L 328 1 Defect Active BERR-SF 0 0 OK BERR-SD 0 0 OK ES-L 329 SES-L 329 UAS-L 318 ES-LFE 0 SES-LFE 0 UAS-LFE 0 SONET path: BIP-B3 0 0 REI-P 0 0 LOP-P 1 1 OK AIS-P 328 1 Defect Active RDI-P 0 0 OK UNEQ-P 0 0 OK PLM-P 328 1 Defect Active ES-P 329 SES-P 329 UAS-P 318 ES-PFE 0 SES-PFE 0 UAS-PFE 0 [...Output truncated...]
Meaning
The sample output details where the errors might be occurring. Error details include input and output errors, active alarms and defects, and media-specific errors. The SONET section, line, and path errors help narrow down the source of the problem.
If the physical link is down, look at the active alarms and defects for the SONET interface and troubleshoot the SONET media accordingly. SeeList of Common SONET Alarms and Errors for an explanation of SONET alarms.
Monitoring Statistics for a SONET Interface
Purpose
To monitor statistics for a SONET interface, use the following Junos OS CLI operational mode command:
Action
user@host> monitor interface so-fpc/pic/port
We recommend that you use this command only for diagnostic purposes. Do not leave it on during normal router operations because real-time monitoring of traffic consumes additional CPU and memory resources.
Sample Output
user@router> monitor interface so-1/1/1
router Seconds: 168 Time: 15:48:50 Interface: so-1/1/1, Enabled, Link is Down Encapsulation: Cisco-HDLC, Keepalives, Speed: OC3 Traffic statistics: Current Delta Input bytes: 375527568 (0 bps) [0] Output bytes: 6612857 (0 bps) [475] Input packets: 224001 (0 pps) [0] Output packets: 102090 (0 pps) [20] Encapsulation statistics: Input keepalives: 0 [0] Output keepalives: 176 [17] Error statistics: Input errors: 0 [0] Input drops: 0 [0] Input framing errors: 179 [17] Policed discards: 47 [0] L3 incompletes: 0 [0] L2 channel errors: 0 [0] L2 mismatch timeouts: 0 [0] Carrier transitions: 1 [0] Output errors: 0 [0] Output drops: 0 [0] F2 : 0x00 Z3 : 0x00 Z4 : 0x00 Interface warnings: o Received keepalive count is zero o Framing errors are increasing, check FCS configuration and link Next='n', Quit='q' or ESC, Freeze='f', Thaw='t', Clear='c', Interface='i'
Meaning
This output checks for and displays common interface failures, whether or not loopback is detected, and any increases in framing errors. Information from this command can help you narrow down possible causes of an interface problem.
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 statistics since the monitor interface interface-name command was executed.
If the framing errors are increasing, verify that the frame check sequence (FCS) and scrambling configuration match on both ends of the connection. If the configuration is correct, check the cabling to the router and have the carrier verify the integrity of the line.
If the input errors are increasing, check the cabling to the router and have the carrier verify the integrity of the line.
If you are sending output keepalives but are not receiving any input keepalives, verify that the encapsulation and keepalive configurations match on both ends of the connection.
Table 3 lists and describes the SONET error statistics in the output for the monitor interface command. The output fields are listed in the order in which they appear in the output.
Table 3: SONET Error Statistics
Output Field | Output Field Description |
---|---|
Input errors | Sum of the incoming frame aborts and FCS errors. |
Input drops | Number of packets dropped by the output queue of the I/O Manager ASIC. If the interface is saturated, this number increments once for every packet that is dropped by the ASIC’s random early detection (RED) mechanism. |
Input framing errors | The number of packets that have FCS errors. |
Policed discards | Frames that the incoming packet match code discarded because they were not recognized or of interest. Usually, this field reports protocols that the Junos OS does not handle. |
L3 incompletes | Increments when the incoming packet fails Layer 3 (usually IPv4) sanity checks of the header. For example, a frame with less than 20 bytes of available IP header would be discarded and this counter would increment. |
L2 channel errors | Increments when the software cannot find a valid logical interface for an incoming frame. |
L2 mismatch timeouts | Count of malformed or short packets that cause the incoming packet handler to discard the frame as unreadable. |
Carrier transitions | Number of times the interface has gone from down to up. This number should not increment quickly, increasing only when the cable is unplugged, the far-end system is powered down and up, or a similar problem occurs. If it increments quickly (perhaps once every 10 seconds), then the cable, the far-end system, or the PIC is broken. |
Output errors | Sum of the outgoing frame aborts and FCS errors. Because output errors are rare, hardware problems, configuration, or software bugs might contribute to the cause of them. Use the output of the show interfaces type-fpc/pic/port extensive command for more details about which output errors are incrementing. Also, analyze the system or interface load to determine if those areas are contributing to the cause of the problem. If the problem persists, open a case with the Juniper Networks Technical Assistance Center (JTAC) at support@juniper.net or at 1-888-314-JTAC (within the United States) or 1-408-745-9500 (from outside the United States). |
Output drops | Number of packets dropped by the output queue of the I/O Manager ASIC. If the interface is saturated, this number increments once for every packet that is dropped by the ASIC’s RED mechanism. |
See also
Verifying the Status of the Logical Interface
Purpose
To verify the status of the logical interface, use the following two Junos OS CLI operational mode commands:
Action
user@host> show interfaces so-fpc/pic/port
user@host> show interfaces so-fpc/pic/port terse
Sample Output 1
The following sample output displays the information for a logical interface that is up:
user@host> show interfaces so-2/2/0 Physical interface: so-2/2/0, Enabled, Physical link is Up Interface index: 21, SNMP ifIndex: 45 Link-level type: Cisco-HDLC, MTU: 4474, Clocking: Internal, SONET mode, Speed: OC3, Loopback: None FCS: 16, Payload scrambler: Enabled Device flags : Present Running Interface flags: Point-To-Point SNMP-Traps Link flags : No-Keepalives Input rate : 0 bps (0 pps) Output rate : 0 bps (0 pps) SONET alarms : None SONET defects : None Logical interface so-2/2/0.0 (Index 7) (SNMP ifIndex 33) Flags: Point-To-Point SNMP-Traps Encapsulation: Cisco-HDLC Protocol inet, MTU: 4470, Flags: None Addresses, Flags: Is-Preferred Is-Primary Destination: 10.0.2/24, Local: 10.0.2.1 user@host> show interfaces so-2/2/0 terse Interface Admin Link Proto Local Remote so-2/2/0 up up so-2/2/0.0 up up inet 10.0.2.1/24
Sample Output 2
The following sample output displays the information for a logical interface that is down:
user@host> show interfaces so-2/2/0 Physical interface: so-2/2/0, Enabled, Physical link is Up Interface index: 21, SNMP ifIndex: 45 Link-level type: Cisco-HDLC, MTU: 4474, Clocking: Internal, SONET mode, Speed: OC3, Loopback: None, FCS: 16, Payload scrambler: Enabled Device flags : Present Running Loop-Detected Interface flags: Link-Layer-Down Point-To-Point SNMP-Traps Link flags : Keepalives Keepalive settings: Interval 10 seconds, Up-count 1, Down-count 3 Keepalive: Input: 14 (00:00:05 ago), Output: 14 (00:00:05 ago) Input rate : 0 bps (0 pps) Output rate : 0 bps (0 pps) SONET alarms : None SONET defects : None Logical interface so-2/2/0.0 (Index 7) (SNMP ifIndex 33) Flags: Device-Down Point-To-Point SNMP-Traps Encapsulation: Cisco-HDLC Protocol inet, MTU: 4470, Flags: None Addresses, Flags: Dest-route-down Is-Preferred Is-Primary Destination: 10.0.2/24, Local: 10.0.2.1 user@host> show interfaces so-2/2/0 terse Interface Admin Link Proto Local Remote so-2/2/0 up down so-2/2/0.0 up down inet 10.0.2.1/24
Meaning
In the sample output 1, the show interfaces command in sample output 1 shows that the logical link is up because there are no flags indicating that the link layer is down. The output for the show interfaces terse command shows that logical interface so-2/2/0.0 is up.
Both commands in sample output 2 show that the logical interface is down. The first command shows that the link layer, device, and destination route are all down. The second command shows that logical interface so-2/2/0.0 is down.