Cisco IOS SIP dial-peer status notifications

This configuration will create a syslog message as well as an SNMP trap either of which your monitoring/alerting systems should be able to use as a trigger to take action.

1. Copy the linked TCL file to the root of the flash filesystem on the router that connects to the SIP trunk(s). Download TCL Script
2. Add the command to “voice-class sip options-keepalive” to one of the dial-peers pointing to the service provider and make a note of the dial-peer number you are adding the command to


dial-peer voice 100 voip
voice-class sip options-keepalive

3. Add the command track 100 stub-object to the global config.
4. Add the command snmp-server enable traps event-manager to the global config (this is needed for the SNMP trap functionality).

4. Finally the following configuration template can be applied to the router. Notice the number 100 below is a reference to the dial-peer and tracking number from above and must match for this to work.

event manager environment dial_peer_number 100
event manager environment check_interval 30
event manager directory user policy "flash:/"
event manager applet siptrunk_down
event track 100 state down
action 10 snmp-trap strdata "SIP Trunk Down"
action 20 syslog msg "Alert - SIP Trunk Down"
event manager policy check_dial_peer_status.tcl

This was documented at the following Cisco page as well: Link

Cisco IP Phone 7900 Reset Sequences

Most of the time Cisco IP phones boot up correctly and attempt to locate the appropriate network resources (CallManager IP, TFTP server, IP address, default gateway, DNS, etc.).

Occasionally this process doesn’t work correctly due to firmware issues or a failed firmware upgrade/downgrade. When this happens there are two reset sequences that may bring your phone back to life! Both procedures are nearly the same, but use different digit strings based on the type of reset you wish to perform. The first process removes all the phone configuration stored on the phone. The second process formats the flash memory on the phone and removes the firmware itself.

1. Unplug the power cable from the phone and then plug it back in.

The phone begins its power-up cycle.

2. While the phone is powering up, and before the Speaker button flashes on and off, press and hold #.

Continue to hold # until each line button flashes on and off in sequence in amber.

3. Release # and press

process 1 use 123456789*0#

process 2 use 3491672850*#

You can press a key twice in a row, but if you press the keys out of sequence, the factory reset will not take place.

After you press these keys, the line buttons on the phone flash red, and the phone goes through the factory reset process.

Do not power down the phone until it completes the factory reset process, and the main screen appears.

If you followed process 2 be prepared to wait for up to 20 minutes for the phone to retrieve a copy of the firmware image from the TFTP server. Remember that since you removed the firmware completely there won’t even be the comforting Cisco labeled splash screen on startup. Be patient!

SRST incoming calls ring to different number

An H.323 gateway configured with the “connection plar” command to a directory number that can only be reached over the WAN can cause issues in the event that the WAN is down. The alias command under call-manager-fallback can re-direct calls during SRST operation. A sample config is as follows:

voice-port 0/1/0
connection plar 1000

alias 1 1000 to 1234 cfw 5551212 timeout 18

Incoming calls to port 0/1/0 while in SRST will ring to extension 1234 and after 18 seconds will call forward to 5551212. An appropriate H.323 dial-peer needs to be present to process 5551212