Technical data

109
D-channel monitor mode
In monitor mode, the D-channel monitor runs in the background as daemon and reports status changes of layer
1 and (or) layer 2 to the user applications that are executed if the status changes.
To start the D-channel monitoring tool in monitor mode, execute: divactrl dchannel -c <x> -monitor <y>
[<parameters>]
D-channel monitor mandatory parameters
Param
eter
Description
x The logical board number to be traced.
y The user application [a] to be executed if the state of layer 1 or layer 2 changes. [b] This application is
called with three parameters: 1 - Logical board number, 2 - Layer that changes its state (1 for layer 1,
and 2 for layer 2), 3 - State after change (1 - UP, 0 - DOWN). The included dchannel_monitor sample
application (shell script) can be used to notify the system administrator via email.
Notes:
[a] The dchannel_monitor shell script is provided as example and can be used to notify the system
administrator (root account) about the link state via email.
[b] If the D-channel monitor fails to start the application or the application exits with an error, the D-channel
monitor will report the failure to the system log.
D-channel monitor optional parameters
Parame
ter
Description
-l1off Does not monitor changes of the layer 1 status
-l2off Does not monitor changes of the layer 2 status. This might be necessary for BRI interfaces if layer 2 is
controlled by the NT side or is established "on Demand"
-syslog Redirects output to the system log file. Every record in system log will receive a header that contains the
logical board number, board name, and the board's serial number
-
dmonitor
This option allows you to output additional trace information to the system log. See the example in D-
channel trace mode on page 107.