Requirements : Network and Firewall Requirements : HA‑to‑DR Communications
  
HA‑to‑DR Communications
The following ports must be accessible between the HA and the DR Appliance pairs across WAN or LAN:
Direction
Port
Protocol
Purpose
Inbound & Outbound
22
TCP
Allows secure TCP connections between onQ Appliances. May be remapped.
Inbound & Outbound
81
TCP
Allows inter‑appliance link monitoring. May be remapped.