Nortel phone issue

[subarusyd]

Hi,

i am new to nortel network and i have recently joined a company. The whole network consists of NORTEL ERS5520 baystack switches. We have nortel phones and they recieve DHCP from Solaris DHCP server. They configured to FULL DHCP and they keep dropping out. They connect eventually after two or three tries but its happening randomly over the network. If somebody could please tell me what kind of troubleshooting steps or diagnostics do i need to do in order to diagnose the problem it would be great as you would be save somebody's job. many thanks in advance. What info do i need to provide?

[Michael McNamara]

Hi subarusyd and welcome to the forums!

Once the phones are up and running is there any issue and/or problem? How is the voice quality of both internal and PSTN calls? I'm going to guess that you might need to look at how you have configured QoS within your network. If your phones are rebooting themselves that's a clear indication of a QoS problem between the phones and the Call Server.

Let us know what you find.

Good Luck!

[subarusyd]

Hi Michael,

                    Thanks so much for your reply. You can't imagine the relief i get when i see your reply. I have gone through all your posts and you are a "Nortel God".  . Anyways, I am new to nortel config and i have worked in cisco before. We have only one VLAN32 configured for phones. The phones we run are IP 2001, IP 2002, IP 2004. They have been running since three years on the same firmware and no upgrades since. The voice quality for both seems to be fine. The line goes silent some time, reboots the phone and asks for DHCP and goes through eventually. Raised a job with Nortel and they ruled it as network issue. when phones start they seem ok, only dropping off is the issue. The issue is getting really serious now. we also suffer from Congestion of network sometimes. the port everywhere acts as a data or phone port depends on what is plugged in.The qos is setup as following:

! *** QOS ***
!
qos agent reset-default
qos if-group name IPTRole class untrusted
qos if-group name LinkRole class trusted
qos if-assign port 1/1-44 name IPTRole
qos if-assign port 1/45-48 name LinkRole
qos if-assign port 2/1-44 name IPTRole
qos if-assign port 2/45-48 name LinkRole
qos if-assign port 3/ALL,4/ALL name IPTRole
interface FastEthernet ALL
exit
qos l2-element 1 vlan-min 32 vlan-max 32 ethertype 0x800
qos classifier 1 set-id 1 name IPTClass element-type l2 element-id 1
qos agent nvram-delay 10
qos agent buffer large

qos agent queue-set 2
qos policy 1 name IPTPolicy if-group IPTRole clfr-type classifier clfr-id 1 in-profile-action 7 precedence 9
qos egressmap name "Standard Service" ds 0 1p 0 dp high-drop
....
....
qos ingressmap name "Bronze Service" 1p 2 ds 10
qos ingressmap name "Silver Service" 1p 3 ds 18
qos ingressmap name "Gold Service" 1p 4 ds 26
qos ingressmap name "Platinum Service" 1p 5 ds 34
qos ingressmap name "Premium Service" 1p 6 ds 46
qos ingressmap name "Network Service" 1p 7 ds 48
qos queue-set-assignment queue-set 1 1p 0 queue 1
...
...
qos queue-set-assignment queue-set 8 1p 7 queue 1

This seems to be the same setup with all the other switches and affecting all sites. The site which does not have this issue at all is setup as QOS:

qos agent reset-default
interface fastethernet all
exit
qos agent nvram-delay 10
qos agent buffer large
qos agent queue-set 2
........
and so on

Can you please tell me what exactly i should be looking out for Nortel QOS issue?. Any suggestions for further diagnosis would be great?.

Thanks
michael

[Michael McNamara]

Your configuration looks good on the phone side although you could be setting the in-profile-action to 6 not 7. How about the Ethernet switch ports that connect the Call Server and Voice Gateway Media Cards?

You should configured each port that connects to the Call Server (ELAN, TLAN) and Voice Gateway Media Card (ELAN, TLAN) as trusted. You can do that by creating another QoS interface group and then add the necessary ports to that group.

qos if-group name CallServer class trusted
interface fastEthernet 1/10,1/11
qos if-assign port 1/10,1/11 name CallServer
exit

It definitely sounds like the phones are experiencing a watchdog timeout and are rebooting. There is a keep-alive that is sent between the Call Server and the phones. If the phone fails to see enough of these packets they automatically reboot themselves thinking there's a problem.

There are a few posts in the Ethernet Switching forum that might be of interest, search for "QoS" and see if anything there helps fill in the blanks.

Cheers!