Why is ping to HA2 peer IP does not work?

What causes firewall HA2 ping does not work?

PA-5250-A(active)> ping source 2.2.2.1 host 2.2.2.2
bind: Cannot assign requested address

PA-5250-A HA2 configuration    
HA2 Data Link Information:      
IP Address: 2.2.2.1/24

PA-5250-B HA2 configuration 
HA2 Data Link Information:
IP Address: 2.2.2.2/24

• Palo Alto Networks Firewalls
• Supported PAN-OS
• HA2 configuration

1. This is expected behavior as HA2 configuration is communicated between devices via the existing HA1 link.
2. HA2 configuration does not have Peer IP Address assignment option (unlike HA1 and HA1 backup).