Bert Testing

loopback local

Puts the locally attached DSU (Internal to the Router) in Loop. This allows the testing of the local Card for errors with the line driver or modulator

loopback remote

Requests a loopback from the remote DSU. This allows the testing of the full circuit up to the DSU at the far end.

loopback network

Sets the local controller to loop towards the network allowing the far end to run test patterns across the entire path.

Testing Examples:

controller t3 1/0 !-- test the local hardware
 loopback local
 !
 bert pattern 0s interval 1
 do show controller t1 0/0
 !
 bert pattern 1s interval 1
 do show controller t1 0/0
 !
 bert pattern alt-0-1 interval 1
 do show controller t1 0/0
 !
 no loopback

controller t3 1/0 !-- test to the remote DSU.
 loopback remote
 bert pattern 0s interval 1
 do show controller t3 1/0
 !
 bert pattern 1s interval 1
 do show controller t3 1/0
 !
 bert pattern alt-0-1 interval 1
 do show controller t3 1/0
 !
 no loopback

controller t3 1/0 !-- allow the far end to perform end-to-end testing.
 loopback network
 !
 !-- WAIT FOR TESTING AT FAR END TO COMPLETE..
 !
 no loopback
!
end

Circuit Locating

You can transmit endpoint location information across a circuit using the ANSI Maintenance Description Set. The following example shows how this is specified:

Circuit Labeling Example:

controller t3 1/0 !-- Identification notation transmited via ANSI MDL Frames
 mdl string eic RouterA     !-- Equiptment ID Code
 mdl string fic 0x01        !-- Frame ID Code
 mdl string generator gen-1 !-- Generator Number in MDL Test Signal Message
 mdl string lic OKC         !-- Location ID Code
 mdl string pfi DT          !-- Facility ID Code
 mdl string port 1-0        !-- Port Number in MDL Idle Signal Message
 mdl string unit 2          !-- Unit Code
 !
 mdl transmit test-signal
!
end

Viewing example at far end of circuit:

show controllers t3 1/0

Results:
T3 1/0 is up.
  Applique type is Subrate T3
  Transmitter is sending AIS.
  Receiver has no alarms.
  MDL transmission is enabled
     EIC: Router-B, LIC: TUL, FIC: FO, UNIT: 1
  Far-End MDL Information Received
     EIC: Router-A, LIC: OKC, FIC: DT, UNIT: 1
  FEAC code received: No code is being received
  Framing is C-BIT Parity, Line Code is B3ZS, Clock Source is Line
  Data in current interval (30 seconds elapsed):
     0 Line Code Violations, 0 P-bit Coding Violation
     0 C-bit Coding Violation, 0 P-bit Err Secs
     0 P-bit Severely Err Secs, 0 Severely Err Framing Secs
     0 Unavailable Secs, 0 Line Errored Secs
     0 C-bit Errored Secs, 0 C-bit Severely Errored Secs
!
end

I’m always looking for this, so I figure here is as good as any for safe keeping.. It’s simple to use…

1. Press Alt-F11 in Excel to get to the VBA screen.
2. Right click on the Project View
3. Click Add Module
4. Add the following snippet.
5. Use: GetHostname("4.2.2.1") in any Excel cell.

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