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Monitoring PSTN line status instead of FXO interfaces




I need assistance on how to monitoring FXO interfaces on PRTG

As you know the FXO card is responsible for terminating analogue lines from the PSTN provider,

now when the port is up the status will be like this:

0/0/0-- fxo-lsupdorm idleon-hooky
0/0/1-- fxo-lsupdorm idleon-hooky
0/0/2-- fxo-lsupdorm idleon-hooky
0/0/3-- fxo-lsupdorm idleon-hooky

The problem is, either the PSTN line is working or not; the status of the FXO port stays the same (up,dorm,idle,on-hook),

What i need is to find a way to determine if the PSTN line is up or not. Do you know any way to monitor this on a 2800 series cisco router?

fxo prtg snmp voice-ports

Created on Feb 25, 2022 5:46:15 PM

Last change on Mar 2, 2022 2:40:56 PM by  Chan Siau Hen [Paessler Technical Support]

1 Reply



Hello there,

Thanks for your KB post.

Do you know if the Cisco device has an OID that reflects the PSTN Line status? If yes, you can use our SNMP Custom Sensor with that specific OID.

Besides that, please also research and check with Cisco for every possibility to get the PSTN Line status including API? We have some rest custom sensor that can actually fetch the status back to PRTG.

If none of the above help, 'and' the PSTN result can be obtained via CLI. The last option is you need to write a script to SSH to the device to get the result. Our EXE sensors support that.


With kind regards,
Chan Siau Hen
Technical Support Team, Paessler AG

Created on Mar 2, 2022 2:38:44 PM by  Chan Siau Hen [Paessler Technical Support]

Last change on Mar 2, 2022 2:39:51 PM by  Chan Siau Hen [Paessler Technical Support]

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