MOH Issues and Resolution

There are quite a few issues which you may come across while configuring Music on Hold. As of SRST/ITS 3.0 an IOS branch gateway has the capability to function as a multicast Music on Hold (MoH) resource. This allows for a distributed MoH design where MoH at remote sites is provided by the local gateway, which can save valuable bandwidth by not having to stream MoH across the WAN. The MoH capabilities of IOS are very simple. IOS can be configured to permanently multicast RTP packets from an audio file stored locally on flash. This multicasting/streaming is not under the … Continue reading MOH Issues and Resolution

How to resolve Replication Issues

So many times in real world you will come across ‘Database replication Issues’. Replication Issues are also very much possible during your CCIE lab so one must be prepare to deal with such Issues. How can you find if your cluster has proper replication? Here are few tools to find out replication Issues: RTMT: RTMT (Real-time monitoring Tool) is a very useful tool for not only checking replication Issues but for lot of other stuff. I will discuss RTMT in detail in some other section. To find out replication status using RTMT, you will need to click the ‘Call manager’ … Continue reading How to resolve Replication Issues

Scenario#2 – Extension Mobility won’t work CUCM 6.1.1

I have come across so many customers who have the same issue – Extension mobility won’t work when you try to login. It will log you in but then quickly logs out the users. The only workaround is as follows: Restart the TFTP service on all servers Restart the Extension mobility service on Publisher Restart the Call manager service across the cluster This bug has been found in 6.1.1. Continue reading Scenario#2 – Extension Mobility won’t work CUCM 6.1.1

MOH Configuration

Music on hold is a very useful feature in Call manager which is used for streaming music when you put a PSTN phone or an internal IP phone on hold. I will discuss briefly how it is configured and how you may use CUCM to stream music from remote gateways. Go to Media Resources > Music on Hold Source Check the box ‘Allow Multicasting’  Go to Media Resources > Music on Hold Server Select the device pool – DP-MOH (This device pool should have a region REG-MOH which has G711 codec with all other regions Create a MRG and select … Continue reading MOH Configuration

IP Phone Background Image

Background Image on Gen 2 and Gen 3 Cisco IP phones can be changed by using the following procedure. I will be showing you how to do for a Cisco 7965 IP phone but the same procedure can be used for other IP phones (like 7941. 7961, 7945 etc). The only difference between different family of phones will be the Image sizes. 1) Resize the Images as per 7965 Phone. 2) Full size image— 320 pixels (width) X 212 pixels (height) and the thumbnail image— 80 pixels (width) X 53 pixels (height). 3) Save the full size file as ‘large.png’ … Continue reading IP Phone Background Image

Scenario#1 – VG224 – Strange DTMF behaviour

Problem description: One of my customer reported an issue with their VG224. All Polycom conference phones connected to the Vg224 were facing an strange issue of DTMF tones not recognized by PSTN. Users trying to get into a MeetMe conference were having  tough time as their pin was not getting recognised. Analysis & Observations: This issue was passed onto me after some of my colleagues already spent few days trying all sort of things for resolution. I found out from the customer that the phones never worked properly ever since they hooked them in VG224. One thing was clear from … Continue reading Scenario#1 – VG224 – Strange DTMF behaviour

H323 Call Preservation

H323 gateway is a non-survivable endpoint. This means an active call will drop if any call manager goes down. This default behavior of an H323 gateway can be changed by playing with few settings at the CUCM and gateway. At gateway: voice service voip h323 call preserve At CUCM: Allow TCP Keepalive for H323  = False Allow Peer to Preserve Call  = True Restart CCM service of PUB Verification: Make an inbound call from PSTN to the phone. During the call, stop the CCM service at Sub but your call will not drop! This is what you will see at … Continue reading H323 Call Preservation