Multiple remote H323 phones "freezing"

[pc3957]

Hi everyone,

I've got a bit of an issue and I'm pulling my hair out trying to figure this one out.

I have an IP Office 500v2 9.1 with configured with open internet via a public IP (I'm well aware of the security risk, and will be moving it back behind my security appliance. Right now I'm just troubleshooting).

Site 1 has the IP Office and 22 9508 digital phones. Works great.

Site 2 has 8 9608 H323 phones. Each 9608 has the public IP of the IPO configured as its call server and HTTP server. The phone connects, download firmware updates, and "appears" to work just fine. However when several people start making calls, the phones begin to freeze. Sometimes you get audio with no display movement, and sometimes you push the speaker phone and get no dial tone (or any sort of display change). The red light does work for the speakerphone, but no change/audio in the display. Oddly enough, when these phones appear frozen I am still able to push the "A" button on the phone and get in to its status menu.

I thought the problem was port forwarding, thus why I have the IPO on a public IP right now. I've upgraded firmware on all the 9608s and am still having the trouble.

It doesn't happen all the time, but seems to happen more often when I have a lot of calls going on at once.

Any thoughts would be greatly appreciated.

Thanks,
Phil

 

[Pepp77]

Do they have enough bandwidth?

| ACSS SME |

 

[janni78]

ALG och PPolicy Inspection enabled on the Firewall?

"Trying is the first step to failure..." - Homer

 

[IPOtech111]

I'm having the same issue with 9608 sets. Not going over the public internet though. IP Office server is in the customers data center and all the IP phones are at remote locations going over the customers MPLS. Every so often though phones have been freezing up. Nothing happens on the screen when you press any buttons. The only reaction I can get from the phone is if I do a Mute CRAFT I can get into the menu to restart the phone and then it come back up and it is fine. I thought I found a resolution on the Avaya Support site 'Upgrade the phone firmware to 6.6 (currently 6.3.0)
Add the following line “SET ARPDBGMODE 3” in your 46xxsettings.txt' but after doing that and monitoring it for a while I realized that this did not fix the issue. The customer is on Server Edition 9.1 SP7. I'm about to open a SR with Avaya.

 

[gwebster]

@pc3957. Your situation sounds like the phones are operating but intermittently loosing the messages to/from IP Office. The 9608 is a stimulus device - i.e. it simply knows that a button is pressed for example. It sends that information to IP Office and IP Office interprets the button, and sends a message back to the phone as to what to do as a result. This process continues for almost all interactions. If those messages are lost (including being delayed for too long), then the behaviour you are seeing will result.

 

[pc3957]

Hi guys,

Thanks for all the responses. The site with IPO has EoC 10/10 and the site with the 8 remote phones has Cable internet 100/6.

An interesting twist, I have 1 9608 at my house and 1 9608 at another guys house and both those phones continue to work normally even when the 8 9608s at the second office appear to freeze.

I'm just spewing crazy thoughts, hopefully someone can validate:
- Is it possible to have 8 phones in a remote site over NAT? Maybe I need to create a VPN and allow the phones to connect directly to the IPO since there are so many?

Thanks,
Phil

 

[janni78]

Well, you need to check the firewall on the remote site as well.

VPN is preferable though.

"Trying is the first step to failure..." - Homer

 

[qtelcom]

I do not implement "remote phones" for any customers, having a VPN in place gives the least amount of grief in my experience. I've did some for testing purposes and did not have a reliable experience.

 

[Ragnorak]

I'm rusty on the H.323 port specifics, but there is a similar issue with multiple remote SIP phones sharing a single WAN connection. The issue is that all the phones are set to use the same base ports internally. The fix is to increment the base port for SIP and RTP in each subsequent phone by 2 so that each phone uses unique ports. This sounds a good deal like what you are experiencing since the sites with a single phone are fine and it is only the site with multiple phones that is causing the problem. Putting the IPO on a public IP essentially eliminates any firewall or NAT issues on that end.

 

[janni78]

Did you just recommend to put the IPO on a public IP without firewall?

"Trying is the first step to failure..." - Homer

 

[IPGuru]

Ragnorak

Please cease selling IP Office systems Immediately & advise all your customer to find a competent Maintainer to secure their systems.

lie qtelecom we strongly discourage the use of NAT traversal for security & reliability reasons.

it is intended as a quick & dirty means of getting a home user operational, multiple handsets at the same location will almost certainly have issues because they are presenting the same Public IP Address (I believe there is even an Avaya doc saying this does not work)

with 8 handsets in one office implementing a hardware VPN is the no-brainier solution.
for individual homeworkers use the phones built in VPN client & a suitable VPN solution.

NEVER give the IPO a public IP address or make it visible on the internet.


Do things on the cheap & it will cost you dear

 

[qtelcom]

Pretty sure IPGuru meant "like qtelcom", not lie qtelcom... I'm not lying...

 

[IPGuru]

Indeed I did Qtelcom - sorry for any misunderstanding it may have caused.


Do things on the cheap & it will cost you dear

 

[AAC-IT]

PC3957 was the issue resolved?
if the issue was resolved, can you please let me know what it was because i am having similar issues.

 

[pc3957]

Hi everyone,

Sorry I thought I had posted the resolution.

It turns out you can have 1 remote H323 phone at a remote site without VPN, but if you need more than 1 remote phone you must have a VPN installed and use the private IP of the IP Office. Something about the IP Office not knowing which remote phone is communicating with it since through NAT they all come with the same IP address.

Anyways, I connected the two sites with VPN and configure all remote phones to access the private IP of the IP Office and now all works well.

Thanks,
Phil

 

[amriddle01]

It's just Avaya being lazy, the connections although from the same IP connect from different source ports, this is how you differentiate, works fine with Mitel system/ phones in the same scenario