Cisco phone drops callers on hold

[LBY]

From the CUCM call logs, we see that the Voice Gateway sends a BYE message which is causing hold calls to disconnect at the 5 minute mark, meanwhile a rare few get disconnected in 30 seconds at the mark while being on hold.  What setting would cause this and how would I fix it?

-EDIT: This issue began a few patches ago, we never had this problem prior.  All external calls to any Voice VLAN.  Also, this isn't the case for internal calls.

[Elliot Dierksen]

Do you have Moh configured? If not, the problem could be that the gateway (you did not specify what type of PSTN gateway you have, CUBE or TDM) could be configured to drop "idle" calls meaning calls where there is no media stream.. If there is no Moh then there is no media stream when the call is on hold. If it always happens at the same length of hold time, that seems like the most likely cause.

[LBY]

Thanks for responding.  We do have MoH configured.  The gateway is just TDM.  We also have a Rendezvous Point configured from the core switch, but we have already troubleshoot this.

[Elliot Dierksen]

Does that mean you are doing multicast MoH? That requires some additional configuration if if the gateway and the MMoH server are not on the same IP network/VLAN. Unless you have a lot of callers on hold, MMoH may not be the way to go. Have you tried forcing the gateway to use an MRGL that only includes unicast MoH sources? The MoH audio source is selected from the configuration of the phone which placed the call on hold. The MoH server from which that source is played is based on the MRGL of the gateway where the call entered the network.

[Nithin Eluvathingal]

What do your Voice Gateway logs say? Have you checked whether the call is being disconnected by the gateway or the ITSP? Holding a call for 5 minutes can exhaust users, increasing the chances that they will disconnect the call themselves.

2.12.0.0