| net_bind | fkey | false | true | net_binds.id | email_smtp_smart_host_domains.smart_host | 1.57 | a reference to the port that is being used as a Smart Host |
| total_out_burst | int | true | false | | | 1.57 | the aggregate email burst limit for all emails sent through this host, null means unlimited |
| total_out_rate | float | true | false | | | 1.57 | the sustained email rate for all emails sent through this host, null means unlimited |
| default_domain_out_burst | int | true | false | | | 1.57 | the default per-domain email burst limit when no domain-specific value is provided in email_smtp_smart_host_domains, null means unlimited |
| default_domain_out_rate | float | true | false | | | 1.57 | the default per-domain email rate when no domain-specific value is provided in email_smtp_smart_host_domains, null means unlimited |
