Cannot forward calls between endpoints

[RFC_2549]

Hello,

we have a CUCM where all the phones cannot forward calls between extensions, specifically (the following points are the result of tests with Jabber):

- if the call comes from outside, and the inside tries to turn it to another extension, it remains hanging. The Jabber acknowledges it transferred, but the caller continues to hear the music on hold;

- if the call starts from an extension, and then an attempt is made to transfer to another extension, the call is cut down.

So if You call from outside, the jabber answers. The jabber forwards and the caller goes to music on hold. The final called answers the phone, the jabber transfers, disconnects, but the first caller continues to hear the music.

At the moment CUCM and phones are on 2 different subnets separated by a firewall that hasn't any blocking rule between the 2 subnets.

What can we do to better understand the problem and possibly solve it?

Thank You

Kind regards

Giulia

[Elliot Dierksen]

Is there any NAT being done between the two subnets? Does the firewall have application inspection for SIP and SCCP (if you have any SCCP phones)? Do the logs in the firewall indicate any block or protocol failures?

[RFC_2549]

Hello, we asked to check the firewall and the response is: no NAT, no inspection and no logs about blocks of protocol failure...maybe we can check something on the VGW?

Thank You

Kind regars

Giulia

[Elliot Dierksen]

You can certainly start there. What kind of gateway? I mean protocol more than hardware model, although more information is better. Making a guess that it might be a SIP gateway, "debug ccsip mess" is a good place to start to see what is going on.

[Scott Leport]

The gateway debugs would be good as that would tell us a bit more about the issue. A sanitised show run of your gateway would also be helpful, if you wouldn't mind sharing?

Do you know if you have the same issues from IP phones / handsets?

Assuming the Jabber users are working in the office, they will likely have an IP address on your data VLAN. If you're phones are on their own voice VLAN and on a different VLAN to CUCM, then you may want to get the Firewall team to confirm that your data VLAN has the same allowances in place on your Firewall.

[4ayoub.aly.754d]

I expect that you would know that a shorter MOH record might loop if the holde continues to be on maintain? With which you’re client may have any individual article on maintain and play music to them for as long as each person have the patience to wait on hold.

[JFOXP]

Hi, Did you ever resolve this issue? It smells of a networking/firewall issue.