# Monitoring Cisco HDLC

You can monitor Cisco HDLC interfaces using the show hdlc interface command.

You can set a statistics baseline for Cisco HDLC interfaces, subinterfaces, or circuits using the baseline hdlc interface serial command.

You can use the filtering feature of the show command to include or exclude lines of output based on a text string you specify. For details, see show Commands in JunosE System Basics Configuration Guide.

| Note: The E120 and E320 routers output for monitor and show commands is identical to output from other E Series routers, except that the E120 and E320 routers output also includes information about the adapter identifier in the interface specifier (slot/adapter/port).

baseline hdlc interface

- Use to set a statistics baseline for Cisco HDLC interfaces. The router implements the baseline by reading and storing the statistics at the time the baseline is set and then subtracting this baseline whenever baseline-relative statistics are retrieved.
- Example
  host1#baseline hdlc interface serial 2/0:1/1
- There is no no version.
- See baseline hdlc interface.

show hdlc interface

- Use to display statistics for the specified HDLC interfaces.
- You can specify the following keywords:
  - statistics—Displays interface statistics
  - delta—Specifies that baselined statistics are to be shown
  - status—Displays the operational status of all configured interfaces
  - closed—Displays interfaces with administrative status Closed
  - config—Displays configuration information
  - down—Displays interfaces with operational status Down
  - lower-layer-down—Displays interfaces with operational status LowerLayerDown
  - not-present—Displays interfaces with operational status NotPresent
  - open—Displays interfaces with administrative status Open
  - up—Displays interfaces with operational status Up
  - full—Displays configuration information, status, and statistics
  - filter—Specifies a CLI output filter
- Field descriptions
  - interface status—State of the interface:
    - Up—Traffic can flow on the interface
    - Down—Traffic cannot flow because of a problem in the interface at the current protocol layer
    - LowerLayerDown—Traffic cannot flow because of a problem in an interface at a lower protocol layer
    - NotPresent—Traffic cannot flow because hardware is unavailable
  - Interface administrative status—Configured state of the interface:
    - Open—no hdlc shutdown command is operative
    - Closed—hdlc shutdown command is operative
  - Interface maximum-transmission-unit—Configured MTU size
  - Interface keepalive time—Configured keepalive interval value
  - Interface loop detection—Status of loopback detection: enabled, disabled
  - Interface statistics:
    - packets in—Number of inbound packets received on the interface
    - packets out—Number of outbound packets transmitted on the interface
    - octets in—Number of inbound octets received on the interface
    - octets out—Number of outbound octets transmitted on the interface
    - errors in—Number of inbound errors received on the interface
    - errors out—Number of outbound errors transmitted on the interface
    - discards in—Number of inbound packets discarded on the interface
    - discards out—Number of outbound packets discarded on the interface
- Example 1

      host1#show hdlc interface serial 5/1:5/1
      Cisco-HDLC interface serial 5/1:5/1 is LowerLayerDown

- Example 2

      host1#show hdlc interface full
      Cisco-HDLC interface serial 4/0:2 is Up
      Interface administrative status is open
      Interface maximum-transmission-unit is 1596
      Interface keepalive time is 10 seconds
      Interface loop detection is disabled
      Interface statistics              in                  out
         packets                        0                   0
         octets                         242                 242
         errors                         0                   0
         discards                       0                   0
      Cisco-HDLC interface serial 5/0:1/1 is NotPresent
      2 Cisco-HDLC interfaces found

- See show hdlc interface.