sundance-communications.com/forum Forums TDM Business Telephone Systems Samsung Telephones & Systems OPP Channel Not available

Hello,

I see one other post in the forums similar to my situation, but without any replies other than the original poster. The resolution he had though was to reboot the systems, which I tried and it worked for a few days, but now the issue is back. Here are my specifics. I'm not a phone tech, so I'm kind of guessing on which card is considered the version of the system.

I have 3 sites. The primary is running an iDCS500R2 MCP2 v2.75, with 2 cabinets with 2 MGI16s in one of those cabinets. One of the secondary sites also has an iDCS500R2 MCP2 v2.72, with one MGI3-8 card. The last site is running an OS7100 System 13.04.08 v4.70, and I believe I'm using the built-in MGI channels from the MP20s.

The 3 systems all seemed fine up until a couple of weeks ago when I added more IP phones to the OS7100 system. After doing that I started getting the OPP Channel Not available and having other quirky issues. I don't even really know where to start troubleshooting. Please forgive my lack of experience with these systems, but what I thought I should start with is seeing if my MGI channels are all in use. However, I don't know where to look to see that, or if an OPP channel has anything to do with MGI channels.

I'm not a phone tech and won't claim to be one, but usually I can tinker and click around to at least get a better idea of what might be wrong. I'm completely lost with this so any help to troubleshoot would be appreciated. Thanks in advance

OPP MGI error means the system you are calling doesn't have any spare MGI channels.

I'm guessing it's the OS7100, you probably need to purchase more licenses, the OS7100 can have upto 8 MGI channels onboard

What I've found is that if I reboot the head iDCS500 in site 1 that the others call through, then it works for a few days before coming back. Once it starts happening it seems to be constant until I reboot that one system, and it happens at both site 2 and 3. The systems also were working fine up until the addition of some IP phones at site 3, but I don't see how they would've affected site 2. Any chance there is some feature code that may have been overwritten when adding N-LCR values for call routing that would be a required feature to have? That's the only new thing I've come up with since posting that may have changed around the time the issues popped up.

For the MGI utilization, does every IP phone require an continuously active MGI channel to run, or do they only use one while making/receiving calls or voicemail? If it needs continuous, that might partly explain the other issue I posted about. Also, would the systems be opening MGI channels to talk between each other outside of to pass calls through? Any spot within the system to see current MGI channel utilization?

Thanks in advance

Maybe you already knew this too, but it looks like the channel that gets listed with the OPP Channel Not Available message is from MMC724 under VOIP-NET if that would indicate anything different

IP phones use 2 MGI to talk IP phone to IP phone or a SIP trunk and 1 to talk to voicemail, POTS or digital phones. The 7000 is a little different whereas it uses MPS (if turned on in system options) for IP to IP to conserve MGI channels, it's on by default. I vaguely remember an engineering release note about problems with newer systems utilizing MPS that are connected via SPNET to older idcs and pre 4.6 7000's. I can't imagine MPS is causing your problems all of the sudden but it wouldn't hurt to turn if off in 2.5.1 to be sure.

Thanks for the explanation. If I were calling from a system with IP phones to another site/system, it would be one MGI channel in use from each system, correct?

I did some more testing and it almost seems like my secondary 500 system works, but only is allowing one call at a time now for some reason. I found MMC 432 for connection statuses and didn't see anything connected besides my one call, but any calls after that would get the OPP Channel not available error. The other MGI channels were all open. Hanging up and calling the 2nd number would then work, but trying to call the original from a second line didn't. Incoming calls to that secondary site seem to work fine too. It's just the outbound, which go through the primary 500 system, that seem to be an issue once one of the MGI channels is in use. It looks like the MGI trunks are setup in MMC615 for all options too. I have 32 MGI channels at the head end, and they don't seem to have any usage on them in MMC432 when the OPP error shows up at the remote systems, so I'm still lost.

Wireshark and packet trace to see if the communication is even trying to get through to the head end? Initial communication would happen on the system IPs and then get passed off to the MGIs, correct? Just wondering if I need to Wireshark more than the system IPs.

I think my OS7100 has an MGI card in it too. I see what appears to be 6 MGI trunks from the MP card, but then 16 MGI trunks from an OAS card that appear to be what it's setup to use. I guess I was wrong with thinking I was using the built-in channels.

It's possible you have a bad MGI card in the 500. If you've tried all other options you may want to get a dealer involved who can work with samsung (if you're not one). They still support the legacy product but for a cost.

Thanks for all the ideas. I still haven't tracked it down exactly and have spoken with a dealer on a few different occasions. I finally broke down this morning and did a restore of my system back to January of this year and rebuilt the few changes I had made between then and April when the issue started. So far so good, but it's also only been ~6 hours, so we'll see if it holds.

I've still had some random issues with dropped calls and weird connections, but rebooting the remote location system clears those up. I think the initial problem was database corruption, and now I'm working on connectivity troubleshooting.