I've inherited a SV8100 R9.5 with 7 sites connected to the primary via netlink. Sites are connected via VPN. I have two sites that have started complaining about frequent reboots. They say it happens almost daily. I had them log it for about two weeks and it seems to be between 12 PM and 1 PM. The other office is claiming about 10 AM daily. I don't have logs for the second office. I'm assuming there's some latency around that part of the day. That wouldn't surprise me with a cable internet connection. As far as I know this is a relatively new issue. One of those offices also complains about the phones ringing and no one is there / no caller id, but I don't think that would likely be related.

After digging I have seen numerous posts that essentially blame the internet for being unreliable. I'm fine with it being related to the connectivity, but we have fairly fast VPNs with just a few users at that site.... Is there a setting to make the remote SVs a little more tolerant of a short "blip" in the internet connection? What can be done?

Tylan - here are the settings for the NetLink keep-alive. Maybe this will help.

51-05-01 : Timer Settings for NetLink – Keep Alive Interval
Set the interval (1~3600) for the secondary SV8100 to send the Keep Alive packet to the Primary SV8100 to confirm communication.

51-05-02 : Timer Settings for NetLink – Keep Alive Response Waiting Time
The secondary SV8100 waits this time (0, 5~10800) for response to the Keep Alive packet to confirm communication with Primary SV8100. If no response is received, Fail- Over occurs. A setting of 0 disables this and the SV8100 waits indefinitely for a response from the Primary SV8100.

This one may be of interest as well.

51-05-07 : Timer Settings for NetLink – Communications Socket Refresh Timer
If the IP connection becomes unstable and communication is lost (keep-alive function does not work), the SV8100 retries the connection at this time (20~3600).

OK, I'll check these settings. I'm assuming just increase the timing on by a few seconds.... Any suggestions?

Yes I would adjust just the problem sites, a little bit at a time. You could cause more headaches with these settings.

Tylan,
What are your certifications on the SV8100?
Are you a NEC dealer or reseller?

No NEC affiliations or certs. Actually, I unwillingly inherited this from the IT guy that moved on. The company that installed has since closed. My certifications are on Vertical & Comdial lines. I've just been maintaining this system off and on for a few months. I have access to manuals, but that's it. From my searching, it seems like this problem is common when the netlink runs over the internet. If there's a software update that is needed we will need to find an NEC dealer outside of our area.