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Tanster
Tanster
join:2006-07-08
New York, NY

Tanster

Member

Vonage V-Portal + Linksys RTP300 bollixes call transfer

I have a situation where someone I know used to use a Linksys RTP300 from Vonage then was sent a V-Portal box by Vonage. Without removing the Linksys from the network, they just plugged their phones into the V-Portal. Inbound calls and outbound calls worked fine but transferring calls between numbers (all Vonage numbers) would result in the transferred calls going straight to voicemail regardless of whether the number being transferred to (also a Vonage number) was off-hook or not. Removing the Linksys RTP300 solved the issue. I'm curious as to why. Can anyone explain? Asking Vonage tech support was a waste of time (they couldn't even understand the question!)

NetFixer
From My Cold Dead Hands
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join:2004-06-24
The Boro
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1 edit

NetFixer

Premium Member

I'm not sure that I understand the question either, and unless your acquaintance wants to post here and reconnect the RTP300, and supply some answers to questions I would need to ask, there probably aren't going to be any definitive answers (from me).

As someone who has operated with multiple Vonage routers on the same network, I can say that what you reported them doing should not have worked at all. You have to either go to the on-line Vonage control panel and logically move lines between adapters, or you have to ask a Vonage tech to do it for you. Just plugging a phone into a newly connected adapter would not result in that phone automatically working on the new router.

Also if they had the LAN connections from the two Vonage routers connected as part of a common LAN, then there would have been an IP address conflict on their LAN unless they changed the factory default values on one or both routers, and this would have at best resulted in unpredictable things happening. If they had the Vonage routers connected in a cascade fashion, there would have been routing problems if both routers were left in their factory default condition (with similar unpredictable results as in a parallel connection...if it worked at all).

If Vonage shipped them a replacement V-Portal box because the RTP300 was malfunctioning, then probably a Vonage tech logically moved the line(s) to the new V-Portal box on the Vonage server (and probably assumed that the customer would remove the defective RTP300).

If the RTP300 was actually malfunctioning (even if the customer connected both routers properly and modified one or both to eliminate IP address conflicts), the RTP300 may have also thought that it was controlling the phones (because it did not receive the move instructions from the Vonage server) and that was screwing things up until it was physically removed from the network. I have seen this happen with malfunctioning Vonage routers where two Vonage routers each thought they controlled the same phone number.
Tanster
Tanster
join:2006-07-08
New York, NY

Tanster

Member

Unfortunately, the acquaintance isn't likely to reconnect the RTP300 since the problem is essentially solved by its removal. This question is mainly for my own edification.

The V-Portal was set to DHCP (no static reservations used at the DHCP server and there's only one of them), so the likelihood of conflicting IPs is zero even if the RTP300 was set to a static address. Plus, the V-Portal and the RTP300 *WEREN'T* set up in cascade--both were connected directly to the built-in switch on the firewall. I didn't get a chance to futz with the RTP300 in that upon visual inspection, there appeared to be a vestigial device so I removed it and "then the call transfer miraculously worked." :-/

Where is the control on the Vonage online account for deactivating an old Vonage adapter? I can't seem to find anything there that comes close. It could be that he didn't deactivate his legacy RTP300--this fellow has been known to attempt to have a backup "ready to go" even while not understanding network theory at all, so your last paragraph might be closest to the actual reason for the issue. I guess I'll have to wade through RFC3261 and the related VoIP texts. Thanks for your explanation, though..

NetFixer
From My Cold Dead Hands
Premium Member
join:2004-06-24
The Boro
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Pace 5268AC
TRENDnet TEW-829DRU

NetFixer

Premium Member

said by Tanster:

Unfortunately, the acquaintance isn't likely to reconnect the RTP300 since the problem is essentially solved by its removal. This question is mainly for my own edification.

The V-Portal was set to DHCP (no static reservations used at the DHCP server and there's only one of them), so the likelihood of conflicting IPs is zero even if the RTP300 was set to a static address. Plus, the V-Portal and the RTP300 *WEREN'T* set up in cascade--both were connected directly to the built-in switch on the firewall. I didn't get a chance to futz with the RTP300 in that upon visual inspection, there appeared to be a vestigial device so I removed it and "then the call transfer miraculously worked." :-/

Where is the control on the Vonage online account for deactivating an old Vonage adapter? I can't seem to find anything there that comes close. It could be that he didn't deactivate his legacy RTP300--this fellow has been known to attempt to have a backup "ready to go" even while not understanding network theory at all, so your last paragraph might be closest to the actual reason for the issue. I guess I'll have to wade through RFC3261 and the related VoIP texts. Thanks for your explanation, though..

The IP address conflict would have come into play if the LAN interfaces of the Vonage routers were connected to a common LAN and the customer had not changed the default values for the LAN interfaces. If their LAN interfaces were not connected to anything, that would not have been a problem. Since I knew nothing about your acquaintance's network architecture (and since Vonage usually recommends making their adapter's LAN your LAN), I mentioned that as a possibility. In fact, I have in the past had two Vonage adapters connected to a common LAN as shown in the network diagram image below:




Here is where you get to Adapter Management on the Vonage Dashboard:




Here is my Adapter Management page. Note the message to call Vonage support if an adapter is not functioning properly? I suspect that they would then remove that adapter from your account (and advise you to physically remove it from your network). I have two adapters because I used to have three active Vonage lines, but since my retirement, that need has gone away.




There is no way for the customer to remove/deactivate an adapter from his account, that has to be done by a Vonage tech. You can however, simply move all phone lines from one adapter, and that should remove it from active service. However, if that adapter is defective, then it may still think that it is actively controlling one or both phone lines.

Shown below is where you can tell if a Vonage adapter thinks that it controls a specific phone number. I have on more than one occasion run into cases where two adapters would think that they controlled the same number after a line move command. When that happens, the results are pretty much unpredictable, but the scenario you presented would certainly be a possibility.


Tanster
Tanster
join:2006-07-08
New York, NY

Tanster

Member

Okay, I didn't quite understand what you meant at first. Thanks for the diagrams, by the way.

To clarify: No, the Vonage V-Portal is attached to his LAN via its blue, WAN port and its yellow, LAN port is unattached/unused. The V-Portal's WAN port is set to DHCP client mode and is picking up an address in the 192.168.1.x/24 subnet from the DHCP server on the firewall (I checked by plugging my laptop into the V-Portal's yellow, LAN port and got an IP in the default 192.168.15.y/24 subnet via DHCP before connecting via HTTP into the V-Portal to check its settings).

I've just taken a look at his Vonage adapter page as you described. Multiple RTP300's are listed there but for all of them, like your's, Port 1 and Port 2 are set to "empty" and only his V-Portal has phone numbers assigned.

The (now removed) Linksys RTP300 was attached also via its WAN port with IP setting unknown and nothing else, including no phones, connected to it (which is what confused me and prompted this question. After all, if there are no phones attached and the Vonage online management screen doesn't assign any phone numbers to it, then there should be no SIP traffic out of this box to bollix call transfers even if it's attached to the LAN via its WAN port, no?)

NetFixer
From My Cold Dead Hands
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NetFixer

Premium Member

said by Tanster:

The (now removed) Linksys RTP300 was attached also via its WAN port with IP setting unknown and nothing else, including no phones, connected to it (which is what confused me and prompted this question. After all, if there are no phones attached and the Vonage online management screen doesn't assign any phone numbers to it, then there should be no SIP traffic out of this box to bollix call transfers even if it's attached to the LAN via its WAN port, no?)

I get the impression from "IP setting unknown" that the phone status inside that particular RTP300 was also unknown. If that is the case, then any results would be totally unpredictable.

A Vonage ATA does not need a phone physically connected to it in order to be assigned or accept responsibility for the phone number. The only way it knows that a phone is physically connected is if the phone is off-hook. Also, if a Vonage adapter's WAN has an internet connection, there will be communication initialed by the adapter to a Vonage server because a Vonage server would have no other way to communicate with the adapter (think about it...the device could be anywhere in the world, on any IP address, and is likely behind a NAT router/firewall).

One thing you seem to keep ignoring is if a device is malfunctioning, the normal rules don't apply.

The only way you are going to be able to solve your mystery is to duplicate the event, and then look at the status of all of the adapters involved and the status of the Vonage server. You also need to keep in mind that some of the data you will need is only going to be available to a Vonage tech with the proper authentication credentials to be able to access the information. Also, if the RTP300 in question is not totally dead (as it probably isn't, or you would not see the problem you described), then it may be nearly impossible to duplicate that same symptom again. FWIW, the times I have seen similar symptoms, a power cycle (not just a programmed reboot) of the adapter with the problem would cure the problem.

However, if you connect your Vonage adapters behind a firewall with packet capture capabilities, you would at least be able to see what was being communicated between the adapters and the Vonage server. I have done this in the past when I would see the problem of two adapters both trying to control the same phone number. The sequence of events is that first the Vonage server will send the commands to remove the number from the adapter currently controlling that phone number, and reboot that router. There will then be a waiting period for the original router to reboot and establish a connection to the server so that the server can verify that the original adapter has indeed released control of the phone number. However, if the server does not see a new connection from the original adapter within a reasonable time (several minutes), then it will apparently assume that the original server is either dead or has been removed from service, and it will then assign the phone number to the new adapter. The assumption that the old adapter is either dead or removed from service is what can cause the situation where two adapters both think that they control the same phone number. Without that assumption, a new adapter would never be able to take over a phone number from a dead adapter without intervention from a Vonage tech...which is why Vonage requests that the customer call Vonage support when a malfunctioning adapter is being replaced.
Tanster
Tanster
join:2006-07-08
New York, NY

Tanster

Member

Actually, I'm not "ignoring if a device is malfunctioning." I'm trying to find out what is standard operation to begin with. While I have a fairly complete understanding TCP/IP networking, VoIP is new to me. Until I can determine what is "Standard Operating Procedure" in the VoIP world, I can't tell what's not. I hope this explains my seeming obtuseness.

But thank you for your explanations, though. They come in quite handy as a starting point for my further delving into the world of VoIP.
trekologer
join:2005-10-20
Bridgewater, NJ

trekologer

Member

It sounds like the RTP300 might still have had the phone line(s) configured to it, causing the registration to essentially flip back and forth between the old and new device. Depending on how the replacement device was ordered, the phone line(s) might not have been removed from it right away so that there wasn't a disruption in service. Even if they were, the phone line(s) won't fully be removed from the old RTP300 until it successfully downloads a configuration update which tells the RTP300 that they are no longer assigned. There are a number of reasons why that could fail, too.