XG SFOS 19 Mail Relay MTA route to host with different port

Question

We have an XGS cluster and we want to use the Email protection module in MTA mode. 
 When entering a static route to a mailserver, the emails are normally sent over port 25. 
 When using the Spam protection the normal procedure for blocking non existing recipients is a callout to the server. 
 In Exchange this doesn't work over Port 25 bacause, even with activated Recipient Address Filtering, the filter only works on the Hub Transport connector with port 2525. 
 On Port 25 Exchange accepts any address from a configured domain, regardless of its existence. 
 Therefore the best practice is to route the incoming emails to Port 2525. 
 Unfortunately I cannot find any setting in SFOS 19 tha allows me to change the port.

Vivek Jagad · Answer

Hello AlexanderPoettinger , Thank you for reaching out to the community, You can login to the putty session with SSH protocol with your admin credentials And press 4 for the device console: > For SMTP - console> set service-param SMTP add port 2525 > SMTPS - console> set service-param SMTPS add port <Port number>

Vivek Jagad · Answer

Hello AlexanderPoettinger , In that case you may use a DNAT Option to forward all the traffic hitting to 25 will be forwarded to 2525: > https://docs.sophos.com/nsg/sophos-firewall/18.5/Help/en-us/webhelp/onlinehelp/AdministratorHelp/RulesAndPolicies/NATRules/RulesPoliciesCreateDNATAndFirewallRulesForInternalServers/index.html > https://docs.sophos.com/nsg/sophos-firewall/18.5/Help/en-us/webhelp/onlinehelp/AdministratorHelp/RulesAndPolicies/FirewallRules/FirewallRulesDNATServerAccessAssistant/index.html