I have talked about transitioning from my C4 to either my C5 or C7 many times. I do have a couple devices running on both the C5 and C7 without trouble. But today when I started thinking about the transition it hit me that as I move things, so do I move my repeaters, which will likely cause some devices to quit working. My house is 2 stories around 1600 SF per floor. The big thing is I have a detached building that is around 1000 SF and approximately 100 feet away from the house. I have enjoyed 100% reliability over the past 3 years probably due to placing repeating devices all over the areas. Anyone have any advice on how to make these changes as painless as possible. I have Bruce's excellent transition recommendation, and it would be great if you could just do all of it in one sitting. That won't be happening. So for the time being I am going to just move the most critical devices and rules to the C5.
be on your wifi and pull up your C5/C7 on your phone. start with the devices closest to the hub then work your way out. sure, the C4 stuff will stop working, but the C5/C7 stuff will be fine
It sounds like you have the right idea and understand what I'd say is the biggest possible problem: when moving between hubs, you'll be building and improving one mesh as you destroy the other. Normally, the recommendation is to begin by adding powered devices to a new Z-Wave network, working from the hub outwards in all directions, then add battery-powered devices after this "backbone" is stable. However, if you do that in your case, you'll risk de-stabilizing your existing mesh. Or not; you might be lucky enough it will all keep working, or at least keep working well enough for the few days or however long you need it. Wireless networks are always a bit of a mystery. 
If it were me, I'd probably decide what's most important: getting my new mesh going faster, or keeping my old one functional for a while while I build the new one. Maybe you'll want a sort of "compromise" solution, where you move most repeaters to your new hub but leave a few on your old hub just to (hopefully) keep it working as you finish moving devices between the two. I have no scientific advice for this in terms of how many repeaters on which network, aside from the general recommendation that most homes/networks could use at least one per room...so more of an art, based on how many devices you have and what you want to prioritize.
The good news is that if most of your devices are Z-Wave Plus, they should eventually figure things out on their own on your new (and old) hub. Classic Z-Wave may need a repair, with a per-node repair--a new option on the C-7--being preferred over a full-network repair. Some people advise that it make take several days for larger networks to "stabilize" or at least hours for small ones. So, patience can be helpful.
I'd also advise that you may want to have spare batteries handy for anything battery-powered; I'm not sure if inclusion/exclusion uses more power than regular use (possibly), but as someone who's moved devices between networks a few times, I can tell you that this is the time when I realize that batteries are low/dead--even for previously functioning devices--more than any other!
Thanks for the detailed reply Robert.
You're always spot on with this stuff. The biggest thing that caught my eye about your reply is the "individual" device repair capability of the C7. My gut has been telling me to move to the C5, and skip the C7 for the time being. I reboot my C4 every other day to keep it humming. I seldom have to do this with the C5 or C7, but I have had C7 errors as shown below. Plus the C7 Zigbee radio off/on which I have also had on my C4, but not my C5. I would like to make a single move, and ideally that would be to the latest Hub, but I'm a bit apprehensive about the C7.
Thanks for your time and comments.
Weird, anything running on the C-7 that might cause that? Anything suspicious under the App Stats or Device Stats on "Logs"? If nothing important is there--or anything you don't mind re-doing--maybe a soft reset and a reset of your Z-Wave (and Zigbee, if using it) networks to get a "like new" setup? Or at least a soft reset, not a reset of the radios, and then restoring a local backup (I'd recommend downloading one before this and uploading it during the initial setup screen--tiny option at the bottom, easy to miss)? That might clean up any database corruption if it's the cause of these problems.
The biggest difference between the C-4 and C-5 is a slightly different processor/SoC and a more finely tuned OS. This is the same as the C-7, with the only change between that and the C-5 being the newer Z-Wave hardware and software. The C-4 and C-5 have the same Z-Wave and Zigbee as each other, except adding the option to use the internal radios instead of external. So, I'm not sure you'd get much benefit from moving to the C-5 unless the other changes appeal to you. Just my take!
I have 3 hubs, C3, C4 and C7. I've recently upgraded my rules and LIFX devices to the C7, but left the Zigbee devices (and my only ZWave device) on the the other two hubs, sharing them with Hub Mesh. Everything works extremely smoothly - most devices are on the C3 with some in an outlying part of the house on the C4 (I have two foot thick stone walls so a repeater wouldn't suffice), the C4 is also the development hub.
Using Hub Mesh you can probably transfer your rules/apps piecemeal and keep everything working fairly easily.
I moved from 2 C-4s to 2 C-5s and a C-7... I went with the C-5 for my Zigbee devices and C-7 for Z-Wave. Since I had a spare C-5 I used that for network and cloud devices/apps (Lutron, Homebridge, Alexa etc).
In the past when migrating things from another hub (usually smartthings) I have recommended people set up a framework of repeaters first and then start the unpair/pair process outward moving in.. That way the older hub will still be able to maintain it's mesh to the bitter end. This has actually worked pretty well and allows you to slow roll things a bit.
I doubt it. I have
16 actual devices
40 or so on my mesh from the C4 and C5
3 basic rules
5 Dashboards
79 5.1 rules, mostly small just for tinkering around
1 legacy RM rule
These spammy devices in my log just a short time ago were actually deleted from my C5 hub and had been meshed to the C7
The app and device stats may have a hint of the problem. Never saw numbers that high before. I will do a backup, soft reset and reload to see if that clears things up.
