Wired Intelligent Edge

We have an NBX100 that the All Call Paging that was working fine.  As of a few weeks ago some phones do not receive the page.  I thought it might be the switches since the phones that were not receiving we in the top switch.  I moved one of the switches to the bottom and it did not work.  I double checked the extensions programming and it is allowed to receive paging.  I even setup a page group that only has that phone witrh no success in either switch.

Paging is Layer 2 Multicast  to start , and if youhave a . You do not state if its layer 2 or layer telephones on your network . You say some tels are not recieving a page ?  Are they all on the same subnet  and/or network ?

 I would suggest to start :

1. Reboot the NBX

2. Reboot the switches ( I assume you have a small network )

3. If it still does not work , we need the following  :

NBX version of code you are running

Type of telephones on your network . 2102 . 3102 etc .

Type of switches on your network  3Com 4400 , etc ..

IGMP set up ion the switches ?  Multicast set up ....

Are you running IP on the Fly  ? NBX Protocol Mode ....

Are your telephones running at Layer  2 or Layer 3 ? ( Do your tels have IP addresses assigned to them in a different subnet ? )

We reboot eveything and now the phones do receive the pages but there is a delay until the phones hear it.  At first there is no output but if you do not speak a few seconds it "catches up" and then sends out the page.

NBX100 (10MB uplink)

R6.0.59

(64) 3102 phones

(1) 3103 phone

IP-on-the-Fly

Layer 2 network (All phones, NBX and computers on same LAN)

(2) 3Com SuperStack 3 Switch 4500 PWR 50-Port

Software Version 3Com OS V3.01.00s56p01

IGMP Snooping Disabled

After further testing every time we disconnected 14-16 devices from either 4500 switch the problem clears up.  We believe the problem is either the NBX100 has problems transmitting to all the phones with the 10MB connection or the switches are overloaded.

Are you sure its not one device causing this issue ? 

Can't say that I ever heard Multicast / paging doing that ...