Hi,
Simply, if you would like to connect to the RUT955, then you should use the address of RUT955 connecting over SSH.
Have you tried adding iptable rules to firewall "Custom rules" section?
Network -> Firewall -> Custom rules
Allow All Incoming SSH
iptables -A INPUT -p tcp --dport 22 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
iptables -A OUTPUT -p tcp --sport 22 -m conntrack --ctstate ESTABLISHED -j ACCEPT
Allow Outgoing SSH
iptables -A OUTPUT -p tcp --dport 22 -m conntrack --ctstate NEW,ESTABLISHED -j ACCEPT
iptables -A INPUT -p tcp --sport 22 -m conntrack --ctstate ESTABLISHED -j ACCEPT