Verifying an ISDN PRI Interface and Checking B-Channel Interface Statistics

Purpose

Verify that an ISDN B-channel interface is operating properly. For ISDN PRI, verify that a B-channel interface is configured correctly. (To display a list of B-channel interfaces, enter the show isdn calls command.)

Action

From the CLI, enter the show interfaces extensive command. Alternatively, from the J-Web interface select Monitor>Interfaces>bc-0/0/4:1.

Sample Output

user@host> show interfaces bc-0/0/4:1
extensive

Physical interface: bc-0/0/4:1, Administratively down, Physical link is Up
  Interface index: 145, SNMP ifIndex: 75, Generation: 26
  Type: Serial, Link-level type: Multilink-PPP, MTU: 1510, Clocking: Internal,
  Speed: 64kbps, 
  Parent: br-0/0/4 Interface index 143
  Device flags   : Present Running
  Interface flags: Admin-Test SNMP-Traps 16384
  Link type      : Full-Duplex
  Link flags     : None
  Physical info  : Unspecified
  Hold-times     : Up 0 ms, Down 0 ms
  Current address: Unspecified, Hardware address: Unspecified
  Alternate link address: Unspecified
  CoS queues     : 8 supported, 8 maximum usable queues
  Last flapped   : Never
  Statistics last cleared: Never
  Traffic statistics:
   Input  bytes  :                 5787                    0 bps
   Output bytes  :                 3816                    0 bps
   Input  packets:                  326                    0 pps
   Output packets:                  264                    0 pps
  Input errors:
    Errors: 0, Drops: 0, Framing errors: 0, Runts: 0, Giants: 0, Policed discards: 6,
    Resource errors: 0
  Output errors:
    Carrier transitions: 0, Errors: 0, Drops: 0, MTU errors: 0, Resource errors: 0
    Queue counters      Queued packets   Transmitted Packets   Dropped packets
       0 best-effort            314335                     0                 0
       1 best-effort                 0                     0                 0
       2 best-effort                 5                     0                 0
       3 best-effort              5624                  5624                 0
    Packet Forwarding Engine configuration:
    Destination slot: 5, PLP byte: 1 (0x00)
    CoS transmit queue               Bandwidth               Buffer Priority   Limit
                              %            bps     %           usec
    0 best-effort            95          60800    95              0      low    none
    3 network-control         5           3200     5              0      low    none

  Logical interface bc-0/0/4:1.0 (Index 71) (SNMP ifIndex 61) (Generation 33)
    Flags: Device Down Point-To-Point SNMP-Traps Encapsulation: PPP
    Protocol mlppp, Multilink bundle: dl0.0, MTU: 1506, Generation: 18, Route table: 0

Meaning

The output shows a summary of B-channel interface information. Verify the following information:

The physical interface is Enabled. If the interface is shown as Disabled, do either of the following:
- In the CLI configuration editor, delete the disable statement at the [edit interfaces interface-name] level of the configuration hierarchy.
- In the J-Web configuration editor, clear the Disable check box on the Interfaces>interface-name page.
The physical link is Up. A link state of Down indicates a problem with the interface module, interface port, or physical connection (link-layer errors).
For ISDN BRI, the Parent interface is a br-pim/0/port interface—br-0/0/4 in this example. For ISDN PRI, the Parent interface is a channelized T1 or channelized E1 interface—ct1–pim/0/port or ce1–pim/0/port.
The Last Flapped time is an expected value. The Last Flapped time indicates the last time the physical interface became unavailable and then available again. Unexpected flapping indicates possible link-layer errors.
The traffic statistics reflect expected input and output rates. Verify that the number of inbound and outbound bytes and packets matches expected throughput for the physical interface. To clear the statistics and see only new changes, use the clear interfaces statistics interface-name command.

Verifying an ISDN PRI Interface and Checking B-Channel Interface Statistics

Purpose

Action

Sample Output

Meaning

Related Topics