Details
Email system availability depends in part on best practice strategies for setting tuning configurations. This configuration controls the maximum number of simultaneous outbound connections from a domain and works in conjunction with the Maximum Outbound Connections Count setting as a delivery tuning mechanism. If the limit is too low, connections may be dropped. If the limit is too high, some domains may use a disproportionate resource share, denying access to other domains. Appropriate tuning reduces the risk of data delay or loss.
By default, a limit of 20 simultaneous outbound connections from a domain should be sufficient. The value may be adjusted if justified by local site conditions.
Solution
Update the EDSP to reflect the value for Maximum Domain Connections.
Open the Exchange Management Shell and enter the following command:
Set-TransportService -Identity <'IdentityName'> -MaxPerDomainOutboundConnections 20
Note: The
or
The value as identified by the EDSP that has obtained a signoff with risk acceptance.
Supportive Information
The following resource is also helpful.
This security hardening control applies to the following category of controls within NIST 800-53: System and Communications Protection.This control applies to the following type of system Windows.
References
- 800-53|SC-5(2)
- CAT|II
- CCI|CCI-001095
- Rule-ID|SV-221221r612603_rule
- STIG-ID|EX16-ED-000200
- STIG-Legacy|SV-95233
- STIG-Legacy|V-80523
- Vuln-ID|V-221221