Stuck Trunk \ Locked Out T1 Channel - preventing the channel from being usedThe trunk becomes locked out because the central site modem is stuck in a failed state, causing the T1 card to transmit high AB signaling bits to the Telco switch for that particular channel.
Resolution: Configure MR9600 Controller to look for the locked-out state via the controller's T1 channel poll or T1 signal poll features.
Use command "T1status" to determine if t1channel poll is enabled. Use comand "t1setup" to enable T1 channel poll feature.
Use command "t1sigpoll" to change and determine the status of the T1 signal poll feaute.
Implement only one feature per T1card, "T1sigpoll" or "T1chpoll" not both.
When enabled, the controller queries the T1 card for the receive and transmit signaling states of each T1 channel (a channel can also be referred to as a trunk or DSzero). If a channel reports it's receivie state is different than it's transmit state, the controller will declare this channel to be inconsistent. When the user defined threshold is reached, the modem associated to that channel will be reset.
The user defined threshold must be a value of 90 seconds or greater. The threshold value is a multiplication of the polling "interval" and "threshold".
With MR9600 firmware version 2.42.00, T1Channel poll does not work. Disable T1chpoll and enable T1 sigpoll. As long as the signaling method is NOT loop start.
For released controller versions higher than 2.42, T1 channel poll is the preferred method because of it's compatibility with Loop start lines. Use the command "t1chstatus" to get a snap shot of the channel status. Use "t1debug to get snap shots of receive and transmit signaling bits for each channel.