StarWind Software

have 2 servers, each with 2 NIC.
server A NIC1: 10.1.1.2/24
server A NIC2: 192.168.0.2/30
server B NIC1: 10.1.1.3/24
server B NIC2: 192.168.0.1/30

NIC1 are connected to corporate network
NIC2 are connected to each other using a crossover cable
I can ping any NIC from any server.

HA device works fine if I choose NIC1 for data synchronization channel.
HA device would stay "primary=unknown", "partner=not synchronized", if I choose NIC2 for data synchronization channel.

If so must be there is no connection between NICs 2.

you are absolutely right. starwind's not listening on port 3260 on NIC2 on either server, how do I make it listen on NIC2?

Choose your current host, go to "Configuration" tab, there find option "Network". And check if there is you NIC2 interface, if no - add it and enable.
Also please, note, that for using HA you need port 3261 open.

synchronization worked, thanks!
but i am not clear on how this HA failover worked.
primary keeps forwarding writes to secondary, and when primary become not available, how does the client knows where to find the secondary? the partner has totally different IP and target name. the client learns about the secondary from the primary when it first logs in?

Have you followed our manuals? You should add IPs of both targets to initiator, and MPIO will find out how-to write data to target. Then targets synchronize between each other.

thanks, it worked flawlessly.

Great to hear!