T5542 cams going offline every few minutes

[xSpiffx]

I have a 8 camera setup (7x IPC-T5442TM-AS I bought from Empiretech) and a HDW2549EMP-S-PRO I added later when I also had someone local come out to troubleshoot.
They're all connected to a NVR 5208-8P.
Over the past couple of weeks, the DMSS app has been prompting an update of firmware which I finally actioned today. I'm not sure what was updated.
Immediately after, all the IPC-T5442's have started going offline at random intervals (I can see this when logged into the NVR), although only one offline notification is coming through the DMSS app.

Firmware for the IPC-T5442 is 2.800.150I004.0.R,2020-12-03 for the 3.6mm and 2.840.150G008.0.R,2022-02-18 for the 6mm, and 3.120.150I000.0.R,2024-10-14 for the HDW2549EMP.

I've tried turning Enhancement mode On in PoE which causes all the IPC-T5442 to stay offline (why?), so I turned one back on and I can still see it go offline periodically.
I've tried tinkering with the Encode for that camera from H.265 (which the local security guy changed) to H.264H and H.264, 15FPS, CBR, 4096 Kb/S, with no change.
I've tried unplugging the physical lan cable for 60s then replugging it, with no change.

Any other ideas? And any ideas why it's only affecting the IPC-T5542 cameras? The HDW2549EMP ...after the firmware update has not gone offline at all.

 

[jeremyx]

Going by the versions you posted, the T5442s weren't touched by that update (2020 and 2022 builds), so it was most likely the NVR that got new firmware, and maybe the 2549 as well since its build is from late 2024. You can confirm by checking the build date on the NVR's version info page. A newer NVR build talking to 2020 camera firmware would explain why only the T5442s are dropping.
Two things I'd try:
1. Update the T5442s to current firmware. Since they came from Empiretech, Andy should be able to send the latest build for your exact model and lens. If that takes a while, rolling the NVR back to its previous firmware would also confirm whether the update is the cause.
2. Look at the NVR log around one of the drops. If it shows a network disconnect while the PoE port stays powered, it's a connection issue between the NVR and camera firmware. If the port power drops, it's PoE related.
On Enhancement mode: that's Dahua's long distance PoE mode, which runs the port in a slower link mode meant for long cable runs and ePoE capable cameras. Cameras that don't negotiate it well can fail to come up at all, which matches what you saw, so I'd leave it off for those ports.

 

[xSpiffx]

Thanks. Will give your suggestion a go.