Are the phones getting NAT'd unintentionally (perhaps the entire Voice VLAN)? That might cause the same symptoms.
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Browse All TopicsI'm having a bizarre phone registration issue that TAC is not able to understand , and i'm hoping someone may have ran into the same issue.
I have a Call Manager 7.0.1 server in location A, running in production, with 40 odd phones registered to it fine, everything is working properly.. We have Location B (Remote Site) which we want phones to register on our Call Manager in Location A. Between the sites we have an IPSEC Tunnel running over a netscreen ssg5 and a netscreen 25. I have a separate vlan for voice traffic set at the remote office on the dhcp server, and the phone gets an ip fine, points to the tftp of the call manager here, downloads its' locale and ofhter data,, get's an auto registration DN from our call manager, but then just unregisters itself, with error 'DNS UNKNOWN HOST' . I've confirmed all dns entries for the call managers are correct, and we've even changed the information on the call managers from name to ip ... still no go... i've attached a network diagram(fake ip's) and the console log of the phone and status messages.. hopefully someone can help me out here as i'm at a loss
The problem phone is a 7945, however i've tried with a 7965 at the same location and it has not worked either. IIf, however I install cisco IP communicator on a pc that's on that 3750 switch, it register's fine and functions properly.. (Tried switching the voice vlan of the phones themselves to vlan 1 when noticed the ip communicator worked, however it made no difference)(
The phone registration status on the call manager stays in 'Unknown' status.. And the phone itself has the incorrect time on the display and that's it.. no DN or anything else.
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Hrmm.. Source based routing may make sense here... it's bizarre actually, if i plug something into the 3750 switch at the remote site i can ping everywhere, traceroute etc.. but if i do it directly on the 3750 switch i can't get anywhere.. doesn't hop anywhere.. i'm wondering if it may be more of a routing issue, the only thing that confuses me is that the phone communicates with the call manager, the call manager sees it trying to register, then it just disconnects... odd behavior...
Sangamc: I've disabled SIP ALG but still no luck... i've got nat setup on both trusted sides of the firewall (As most firewall's do) when you say source based Nat'ing is this a config on the juniper itself? Where do i config this or is it a cli?
yes source based NAT is a config that goes on the policy, from the webui if you go to the policy list and click on 'edit' for the policy that would carry traffic from the phone to the server. click on advanced and you will see two different NAT settings for the policy, one is source translation and the other is destination translation. you want to enable source translation in this case.
from the cli this is what my source nat policy looks like
set policy id 1 from "Trust" to "Untrust" "Voip-tel1" "Any" "ANY" nat src permit log
set policy id 1
exit
time to break out wireshark (free network sniffer http://www.wireshark.org/d
some instructions for use with a Cisco switch:
http://supportwiki.cisco.c
hmmm, i didn't preview that cisco link well enough, you basically need only this part
Switch(conf)# monitor session 1 source interface Gi0/1
Switch(conf)# monitor session 1 destination interface Fa0/17
where you specify the source port as the port the phone is using and the destination where the wireshark machine sits (that machine BTW will not be able to do anything else whilst acting as a monitor destination)
Hello Pathix. Since you are getting the image download and basic settings set on the phone you can be pretty sure that your routing, VPN and other network infrastructure are working properly. You should be able to get your phones registering with three quick steps:
1) check that your CCM auto reg is working (i.e. is enabled and there are DN numbers left)
2) open both the remote SSG and NS25 firewalls and disable in ALG (Configuration -> Advanced -> ALG) the following: SCCP, H323 and MGCP.
3) delete the "half" created auto reg entries for the remote phone, and reset them.
After the above, your phones should come up no problem.
*** Technical details: Unfortunately firewall makers and network app makers have never been good at getting together to decide what is good and bad application traffic. Cisco is infamous for not sharing changing to is SCCP and MGCP traffic. In newer CCM 7 and newer phone firmware some of the data sent between the phone devices has changed, which the Netscreen ALG doesnt like. In general, you should often disable this type Application layer checking on firewalls in a multi-site VoIP system. It will cause nothing but headaches.
Hope this works for you.
I'm almost there!! I disabled SCCP, MGCP, RTSP, alg's on both ends of the firewlal, reset the phone, and the phone registered with cm, i could see it saying it waws registered, then within 5 seconds it unregistered itself.. I called the phone and it rang for about 1/8th of a ring then i got a busy signal... but the phone registered which is a step further.. now i get this in the debug display page
16:07:27 Invalid SCCP message! : ID :9b: PrimaryConnection is NULL - close connection and alarm in future 16:07:27 14: Name=SEP0024C4BE4932 Load= SCCP45.8-4-3S Last=UCM-closed-TCP 16:08:23 18: Name=SEP0024C4BE4932 Load= SCCP45.8-4-3S Last=Failback 16:09:23 14: Name=SEP0024C4BE4932 Load= SCCP45.8-4-3S Last=UCM-closed-TCP 16:09:23 Invalid SCCP message! : ID :9b: PrimaryConnection is NULL - close connection and alarm in future 16:09:23 14: Name=SEP0024C4BE4932 Load= SCCP45.8-4-3S Last=UCM-closed-TCP 16:10:18 18: Name=SEP0024C4BE4932 Load= SCCP45.8-4-3S Last=Failback 16:11:18 14: Name=SEP0024C4BE4932 Load= SCCP45.8-4-3S Last=UCM-closed-TCP
Any idea what would cause an invalid sccp message?
Also, make sure "Remote Device" is selected in the CallManager phone properties and that the phones are using the latest firmware for your current 7.0.1 CallManager (and not a later firmware). You should consider upgrading to CallManager 7.1.2a as it fixes a lot of issue, or at least the latest in the 7.0 series.
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by: sangamcPosted on 2009-06-08 at 11:27:09ID: 24574907
i believe the first thing you should do is disable SIP ALG on the juniper devices if it is not already disabled. i have a similar setup without the cisco routers. i also had to enable source based routing on the outgoing juniper policy for the VOIP traffic.