when you say "Network" -- same network, do you mean ethernet or are you asking about ZWave Network?
You probably could have two (or more) on the same ZWave network BUT it doesn't work the way most people would expect.
You are probably hoping that a 2nd hub on the same network could "load balance" or be a failover if one should die. Not gonna happen.
ZWave does not support that. ZWave does use "Secondary Controller" in their offering but it is not what most people think. A secondary Controller in ZWave speak is able to speak for the primary controller during an Include. That's pretty much all the good it can do.
If you join a second hub to the primary, what you get is the ability for TWO controllers to issue commands that only ONE ever sees. So, yes, both hubs can turn that light on or off, but they will probably never know the correct status. It gets worse with sensors. Each sensor (door, motion, leak, etc.) only knows of the primary to send status. Therefore, automations on the second hub, don't work well.
I've had 5 hubs from different manufacturers all on the same ZWave network. I know all the problems.
I started with a Staples Connect and quickly ran into the usual closed hub dilemma: can't keep up with the onslaught of new devices. I then added an Aeon Z-Stick plugged into a MacMini running OpenRemote. It allowed me to create "better" automations and I worked around the lack of accurate status. Then I wanted to add a Linear Garage Door opener and neither Staples or OpenRemote had support for it. Iris did and SmartThings (via the community) did. So I added a SmartThings to my ZWave network. Then I thought Wink would be good and added it. Finally I added Hubitat.. for a total of 5. Today, I have only one powered up. Hubitat.
I was thinking of using my second HUB (without the USB stick) to strictly run all third party apps on it. Things like Influxdb etc.... So that the main HUB won't take a dump if the third party apps take a dump. Is anyone using it in this configuration yet?
I started with the same notion, my 2nd hub would be for only the risky stuff. It's pretty difficult to maintain that wall.
All my "good stuff" is on the primary and thus I either have to expose everything on the primary to the secondary JUST so I can run Homebridge? Yes, Link to Hub is native but 100% is a big load to ship to the secondary.
ABC is another. I could use only Button Controller, but...
InfluxDB is one of the tools that really want 100% of the hub's events. Link to Hub and Homebridge both do that too. For me, I've greatly limited Homebridge to ONLY physical devices. That's all I really care about on the Home App. Dozens of events a day vs thousands.
I got a second hub because some of my stuff was borderline on range from the first hub. Since I got the second hub I've moved devices to the new hub and basically split my house North and South. The original hub I have runs all my rules and what not with the 2 hubs linked to share devices.
Thanks all for the reply. @csteele I ran all the hubs that you mention also and still run Smartthing but just took down my Wink 2 hub. I was asking because I have a garage that sit away from my house. I ran an Ethernet cable there to get good internet coverage and was really thinking about putting a second Hubitat Hub there to just run my garage and Z-wave sensors or Zigbee sensors to offload to a different hub. I really like Hubitat better than Smartthing and slowly moving away from them. Thanks for all that reply it was informative. What a great community.
