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gls101
09-11-2009, 08:56 PM
(Sorry this is so long.....)

I'm having an intermittent outbound problem that's existed since the Voipo TA was installed a couple of weeks ago.

Intermittently, I get a fast busy after dialing a number. I haven't discerned any pattern to the dialed number. It could happen on any particular call attempt.

I've done the following:

1. I had 4 other TA's, plus an asterisk box with 2 SIP and 1 IAX trunks on the network. Things were really confusing, so I unplugged the asterisk server, and all but one of the TA's - a NEXTAlarm PAP2T, using Port 5065. This thing is dead reliable, and for obvious reasons, I can't get rid of this TA. No obvious change to the symptom.

2. I started with a Linksys RVL-200 router. This is a half-way decent VPN router, but I've noticed that it can REALLY be flaky when it wants to (No pattern to it either!). I tried forwarding ports 5060-5062 and 35000-65000 and inputting appropriate firewall rules (boy - I DO NOT like opening so many ports!). Sometimes, the ports don't open when you tell them to, sometimes they do. And the router log is next to useless. I saw no difference in symptom.

3. Because I don't trust the router, even though I like it's VPN capabilities, I dug through the junk box and found a D-Link DI-604, that's pretty basic, but at least it's stable. I tried it initially without forwarding ports or firewall changes, with not much change in the symptom. I then turned on the so-called "Gaming Mode", which, as I understand it turns off SPI. I noticed in the router log that it was blocking ports 5061 and 5062 from what appeared to be a Voipo-used server. So I forwarded 5060-5062 to the static IP address of the TA, and opened the ports in the firewall. Unfortunately, this router doesn't allow ranges of ports to be forwarded, and I wasn't about to individually forward 25000 ports :) so they aren't forwarded. Maybe a slight improvement in failure rate.

By the way, both routers have been updated with the latest available firmware.

4. In another thread I noticed how to get access to server preferences (https://secure.voipo.com/preferences/network). I don't have that selection available to me on my preferences, but the direct link gets me there. I was originally homed to the eastern server. Since Speedtest.net invariably gives me better latency and drastically better download speed (5.5mb/s versus 3.5) on tests to Texas servers versus D.C. servers, I changed my preference to the Midwest server. This has seemed to help somewhat, although the problem is so random that it's hard to quantize it.

5. I tried enabling Voipo STUN. Bad move. It caused the outbound call to go bonkers about 5 seconds into the call, and drop registration on both ports. The ONLY way I could recover was to turn off STUN and point the TA to a different Voipo server. Simply power-cycling it wouldn't bring it back to life. This was repeatable - I could kill it at will. I now have it back pointing to the Midwest server with no STUN.

So that's where I stand. The problem happens now maybe 2 to 3 times a day, versus maybe 4 or 5 before the changes. It doesn't sound like a high occurrence rate, unless you're married to someone who's used to AT&T CallVantage's "it just works". I frequently hear "I want it to work like our old service", and I'm afraid I have to agree with her.

Anyone see anything I've overlooked, or can make any suggestions?

Gary

VOIPoTim
09-11-2009, 09:14 PM
Look and see if you can find a SIP ALG setting in the router. If so, turn it off and reboot the router/ATA and see if it solves it for you.

SIP ALG causes a lot of random issues since it basically tries to be smart enough to manage the traffic and if a call uses a port it doesn't think it should, it will cause issues.

gls101
09-11-2009, 09:48 PM
Look and see if you can find a SIP ALG setting in the router. If so, turn it off and reboot the router/ATA and see if it solves it for you.


No, apparently the router doesn't have a SIP ALG setting. After looking through the router's config screens I couldn't find anything, and I couldn't find anything helpful on google.

While I was going through the router configs I did notice that I had the DHCP server lease duration set for 1 hour. Could that have any effect on the problem? I don't see how it could, but I did bump it out to 1 day.

Gary

quattrohead
09-22-2009, 02:07 PM
I have this happening to me right now, but it goes fast busy about 30-40 seconds into the call. Is yours happening after a call connects or during connection ?

fisamo
09-22-2009, 02:51 PM
Keep in mind that the 35000 - 65000 ports are for the RTP stream. If you're always hearing (normal) two-way audio whenever calls complete, there's no need to worry over these ports. Whichever port you register on should determine call completion (in and out), and 5060 should do fine, unless you're trying to use 5060 on both phone jacks of your ATA...

What happens if you switch "servers" (from central to east, west to central, etc)? I generally stay on East without any incidents, and central seems to be pretty reliable. Seems West has the most issues of late.

gls101
09-28-2009, 08:26 PM
Sorry I didn't get back on this sooner - I've been traveling.

It was happening within a few seconds of dialing.

I've done a couple of things that have for the most part eliminated my problems:

1) I have a Bluetooth adapter that would normally connect between the telco entrance and the telephone instrument. (In other words, it plugs into the PAP2T, and the phone plugs into it.) It intercepts the touchtone outdialing and, depending on a dialed code, can route a call to either the PAP2T or to one of two cell phones. It can also route an inbound cellphone call from either cell phone to the phone instrument.

The adapter listens to the DTMF signaling, initially not passing it to the phone line. If the call is destined for the landline (PAP2T in this case) it repeats the dialing to the line. Apparently, the PAP2T doesn't reliably like the DTMF from the Bluetooth adapter, because I disconnected it and the failure rate improved considerably.

2) When I started with Voipo I had a Linksys RVL200 VPN Router, with the latest available firmware. This thing is the most useless router I've ever seen. Forwarding of ports doesn't work reliably. Same for opening ports. I'll open or forward them, and they will test OK. I'll reboot, and they'll be closed (or open, depending on the phase of the moon). I'll reboot again, and the same ports will be open (or closed, depending on who knows what). Linksys Tech Support (an oxymoron if there ever was one) is clueless. The router is pure garbage.

I switched to an old D-Link DI-602, which at least was stable, but it had very limited support for static DHCP. It actually worked fairly well, but it had a few quirks of it's own. And no VPN, which I missed.

I finally took a spare Linksys WRT54GS and flashed it with the Tomato/OpenVPN distribution. My only regret is I hadn't done this long ago. The thing seems to be dead stable, and I didn't have to forward or open anything to support Voipo. And, I've got OpenVPN, which works great for my needs.

To make a long story short (?), these changes have made about 95% of my problems disappear. I'll keep an eye on the remaining issues, they seem more random than systemic at this point.

Gary