I have BPL580 HW 1 firmware 5.4.7 this is our of warranty and i have another unit BPL580 HW 3 firmware of 5.4.9 can i configure this two unit in HA ?
Configuring high availability with 2 models that have different firmwares and different hardware versions has a high chance of failure.
Some things might not (completely) switch over, or the high availability feature might not work at all when switching from Master to Slave.
You can find a similar topic here: Peplink Balance 380 HA.
My personal advise would be to buy new units, if you want high availability to work like it’s intended to work.