@THSkipper 

What is precisely the symptom of your problem?

Why do you reserve IP addresses?

I suggest no paying too much attention about what is displayed by the app (about devices being offline or online).

  @yves_b my cctv start to randomly offline some take a few seconds to recovery and back to online some a few hours or days

I can't playback or watch the cctv in IMOU app

The reason why I do the reservation because when the cctv is down, i try to ping the camera ip and it goes to other ip like in the screenshot. Ping to .8 but it direct to .108 which is other device and the ping is unsuccessful. After that I ping .108 itself it pings back. The .108 is found out that it is my laptop, so I change laptop ip to a free ip(assume .109)

Then I ping again to .8 it turns to .109 so i don't understand what is happening to them

That mean .108 has the device and somehow there is a conflict for the ip that is why i try to fix as many ip as possible to avoid the crash.

First before this happen, I only fix the cctv ip and NVR  that are 9 ip, the other device are free for DHCP assisgnment.

The problem start at that point some iots (such as door garage,vaccuum robot,xiaomi fan) are randomly offline with the cctv. Imagine how frustrate is this when I need to use them

  @Marvin_S 

After i update new beta FW. It seems ok in the afternoon only 1 or 2 cctv disconnect alarm to my phone and all cctv are online

later that I found out my MI speaker is offline in the evening, so I reboot my Mi speaker and it works well but these are all the alert that coming up.

CCTV / Zigbee Gateway which are stationary suddenly offline like domino.

Even mesh itself offline(this happened many times before the beta FW update)

These are some noti that I had captured.

I found new function in beta version that can monitor the online/offline status of any interested device so I try it.

This is what I can conclude so far for the mesh device.

Even all devices connect to mesh, some device won't show the connected status in the Deco app (I don't know why)

Some device is showed as offline in the app but I can ping their ip anyway and also I can use other wifi app to list all the device in my intranet.
 

When I check the list of devices that online and can be ping for example 20 devices, the mesh that connected shows the list of 15-17 devices only (the number is not steady, up and down every minutes)

I think that some device is keeping connected and disconnected irregularly due to the ip conflict and other reasons.

All of my device has normal or strong connection and they are stationary.

So please fix this asap