How to Setup a Highly Available Smart Home

A smart home is only smart when it works reliably. If your lights stop responding, the heating won’t turn on, security systems stop or routines fail just because the internet goes down or a hub crashes, its not a very smart home. That’s where high availability comes in.

Local Smart Home

Keep devices and automations on your local network (your home WiFi \ wired network) so they continue to work if the internet or cloud services go down. Systems like Home Assistant process everything locally. 

• Run a local smart hub, such as Home Assistant on a Raspberry Pi or a Homey Hub
• For smaller smart home setups, where possible connect devices directly e.g. a Zigbee switch directly to a Zigbee bulb.
• Use multiple smart hubs, if possible. Many smart network can only have one hub per network. Some companies, for example, YoLink allow multiple smart hubs per network

Electric Power Backup and UPS

Use an uninterruptible power supply (UPS), which basically a large battery. Connect all mains powered devices to the UPS, like your smart home hub and your WiFi \ internet router and network switches (if used) to keep your system running during power cuts.

Redundant Internet Connections

Maintain multiple internet links using dual WAN routers or a mobile hotspot as backup. This ensures continuous connectivity during internet connection issues caused by your internet service provider

• Configure automatic failover between your primary and backup internet connections
• Use mobile internet hotspots for quick manual backup
• With multiple connections to the internet, try to use different types. For example used a DSL broadband and fibre connection or a fibre and mobile broadband connection. Don’t use two of the same type as if there’s a problem its likely both connections will stop working.

Redundant Smart Hubs and Failover Hardware

Avoid a single point of failure. Have backup hubs and hardware to maintain functionality if one component fails.

• Keep spare hardware like Zigbee sticks and hub hardware. With regular backups you can restore a backup hub to the primary smart hub very quickly
• SmartThings allows Hub Groups with automatic failover
• Apple HomeKit becomes more resilient with multiple HomePods/Apple TVs

Sensor and Device Redundancy

Duplicate sensors and devices on different protocols ensure coverage if one fails.

• Mix Zigbee, Z-Wave, Wi-Fi, and wired sensors
• Use redundant sensors in important areas
• Try to use battery powered devices when possible. Try to buy mains powered devices with battery backup or use a UPS
• Ensure manual control options where appropriate. For example, a physical key that can open a smart lock.

Local Home Network Design

Use mesh Wi-Fi and \ or wired Ethernet. Keep network equipment on UPS so it functions when there’s a power cut

• Use mesh systems or multiple access points
• Segment IoT devices onto separate VLANs/SSIDs (advanced)
• Keep spare switches or routers available

Automations and Offline Operation

Design automations to continue working during internet outages. Avoid cloud dependent features.

• Keep lighting, alarms, and essential automations local (no internet or cloud)
• Use devices with built-in timers or schedules
• Plan for limited voice assistant functionality
• Use graceful degradation strategies

Backup and Restore Strategies

Protect your configuration and data with regular backups, stored both locally and off-site.

• Automate snapshots or backups regularly
• Upload backups to cloud storage or external drives
• Test your backups on spare hardware or virtual machines

Monitoring and Alerting

Monitor system health to detect issues early. Configure alerts for failed \ failing devices or services.

• Use push notifications or SMS for alerts
• Monitor CPU, memory, disk, and UPS status
• Track network and device uptime with ping or sensors
• Monitor battery levels and signal strength for devices

Advanced Setups

Enthusiasts can implement more complex solutions for full high availability and failover systems.

• High-availability clustering using shared storage and failover software
• Load balancing across multiple Home Assistant instances

By combining local control, backup power supply, network resilience, and automation design, your smart home can stay reliable even when things go wrong. These strategies ensure your smart home system keeps working when the internet \ cloud doesn’t.