I have a question , I have Six SV 8100 linked together over metro Ethernet fiber they randomly will only allow one way communication, meaning you can hear someone but cannot talk to them, they cannot not here you. You can log into the interface reset the unit and everything is normal until the next time.
Have a couple questions

1. The address the units use to communicate with, is it the same address used to access the web interface ?

2. Can you tell me where I can find the MAC address for the card they communicates via the net link card

Thanks for your help in advance

Program 51-11 gives the MAC address of all Netlinked sites. From your post I can tell you are not the vendor or a certified tech so I will try and help what I can. The signaling IP is NOT the same as the Media GW IP. Over fiber meaning what network wise? Do you have a VPN setup or do you have dedicated fiber for just your network? There are many things it can be. Generally in a VPN setup you have ports blocked at a certain range that causes this or you have something that is not lined up on your UDP ports (the media gateway IP) that is making you lose talk paths. I heavily suggest getting the vendor out and verify the network settings, pbx settings and the network. Just remember the media channels do a round robin so ALL the media cards have to be the same size AND same revision. All processors have to be on the same software and MEM cards. The ONLY thing that the primary site can have the inmail.

First thank you for the reply! And to your point I'm not a phone Tech, I am however a very experienced IT Tech. I inherited the phone system from our provider after being bought out then, being handed off to several vendors only to throw their hands up to a problem that's been around since the install including NEC's involvement,
All 8 of our SV8100 sit on a Fiber Ethernet network linked together via Cisco routers, we can see each store, we have 4 digit dialing between stores, and a central operator/ Business Center that handles calls.
The system works perfect, just at times you get only one talk path meaning you can hear them, they can't hear you. Log into Web Pro reset the box and problem is gone, the fact I can reach the web pro tells me its up on the network.
I suspect it communicates via another address, which I was trying to monitor via wire shark which leads to the reason for my question..
I'm familiar with the programs / features of the system to some extent , but certainly no where near your expertise , I was trying to get and understanding of how the systems communicates over the network as it pertains to the Voice path.

Thank you again and I look forward to your input !

It appears netlink is not being Used after your suggestion of looking at 51-11, I did find the additional address under 84-26

The first thing you need to do here is post what software level you have, and all systems need to be the same. Then post what software licensing you have. The Netlink licensing is all loaded into the main system. Also post what size/type of IPLA cards you have specifically in the main system. All of this goes to a possible reason for your issue.
It sounds like you have more IPLA ports than licenses, or more IP addresses assigned than you have DSP ports on the IPLA card. Each time you place a call it uses a DSP off of the IPLA. If you are licensed for less than the number of DPS's or try to use DSP's that do not exist, then you could experience no speech path after the last DPS is used. It will roll over to others in a linear pattern. A reset just puts everything back to DSP 1 and starts over. However, several changes were made in newer software versions that affect this. In 84-26, you assign an IP address for every 16 DSP's you have. So if you have all 8 IP addresses assigned and you only have a 64 port IPLA card then you can experience one way speech when it tries to use DSP 65.

Looking into 84-26 I see only one IP address with ports being used ?

So you know how you are linked together? Netlink or CCIS?

Log in to the system using PCPro, and perform a download. Go to the top and select communications, then feature activation. This will show you what you are licensed for. If you have netlink licenses then you are probably connected through netlink. After you log in the system will show you the firmware level on the bottom.
If 84-26 has one IP address, then you are programmed for 16 DSP's (depending on software and hardware levels. Older software and hardware required one IP address per 16 DSP's, plus one address for the IPLA card. Newer software/hardware required one IP address for the card and only one for all possible DSP's regardless of the size of the IPLA card. If you have older stuff and a 32 IPLA card then you need 3 IP addresses. One for the card and 2 for the 32 DSP's in 84-26. If you have a 32 IPLA with only one IP address in 84-26, then the system could be accessing a port without an IP address, thus resulting in one way speech.

All communication servers in the NetLink network should be at the
same SV8100 software level. After the NetLink network is set up, a
user can press Feature + 5 on their terminal and review the following
information:
• The Terminal System ID
• Primary or Secondary Assignment
• IP Address
• System ID of Current Primary System
• Type of VoIP installed: IPLA/IPLB

More information. Note the last line.
The ports, 58000 and 58002 (TCP) for signaling and the voice ports, are
required to be open at each location. This depends on how many IPLA/B ports
are installed.
IPLA/B 32 open UDP ports 10020 ~ 10083
IPLA/B 64 open UDP ports 10020 ~ 10147
IPLA/B 128 open UDP ports 10020 ~ 10275
For IPLB, only one IP address is needed for each type of IPLB32, IPLB64, or IPLB128.

tried to post some information in the form of screen shots any idea why it wont let me attach a PDF file for everyone to view ?

If you have an IPLB card, then one IP address in 84-26 is correct. If you have an IPLA card then you need to know how large it is 32/64/128 and add IP addresses accordingly.

I have seen this before and the problem seemed to come from the Gateway not replying to valid ARP requests. As the vendor couldn't see anything wrong... (even though i had a packet capture to prove it) I forced the customer to roll out a VLAN just for the systems (Which is always recommended anyway) The problem has not reoccured since!

The other issue could be packets 'flooding the CPU' causing the LAN to reset on the SV8100