If the active unit fails, will there be an automatic failover to the stand-by unit?

No. You must shut down and power off the active server, then follow the instructions below on the secondary node:

Version Mar08SU 1209 and later:

• Navigate to Console Interface > Cluster Configuration.
• Select Make Server Primary.
• Confirm Cluster IP Address has transferred to new primary node.
• Change the IP address under Network Configuration to match the IP of the failed appliance.
• Navigate to Console Interface > System Control > Restart Network.
• Confirm SSH access to Cluster IP Address
• If necessary clear ARP cache on network devices

Versions earlier than Mar08SU 1209:

• Navigate to Console Interface > Network Configuration
• Select Make Server Active
• Confirm Cluster IP Address has transferred to new primary node
• Navigate to Console Interface > System Control > Restart Network
• Confirm SSH access to Cluster IP Address
• If necessary clear ARP cache on network devices