Relay Server

Pro

Operate all kind of settings when connect SMTP with the mail relay source server. You can set the number of simultaneous connections, reception interval, reception size and connection IP.


Setting the relay server

Login to management console and click the server composition tab.

Click the server composition on the server configuration list.

Server settings dialog will be displayed.

Click the relay server settings menu.

relay server settings

Following items will be displayed

Item       Required Description
Conenction port Yes The port number that accepts SMTP connections. This value cannot be changed.
Maximum number of connections Yes Input the maximum number of simultaneous SMTP session connections that can be accepted. Specify in the range of 1-100.
Reception interval Yes Input the interval (processing time per mail) for receiving mail from the mail relay source server in milliseconds. Specify in the range of 10-10000.
Receive size Yes Input the content size of the received email in KByte units.
SMTP authentication Yes Specify whether to use SMTP authentication with the mail relay source server. The account used for SMTP authentication is set in API User.
Authentication method No Specifies the authentication method for SMTP authentication.
Receiving permission when using SMTP authentication,Connect from outside the networkS Yes If you want to use SMTP authentication and restrict the connection source IP address, select "reject". If you want to use SMTP authentication but not restrict the connection source IP address (allow connection only with SMTP authentication), select "do not reject".
Receiving permission
network
No Input the connection IP that allows SMTP connections. This setting is not required if you allow the connection only by SMTP authentication.

Settings will be saved in management console when clicking the save button.


Relation between"SMTP authentication" and "Accepted network"

When using "SMTP authentication", after restricting the connection source IP address on the receiving permission network and then performing SMTP authentication, There is a setting that accepts any connection source IP address and performs SMTP authentication. If you want to perform further SMTP authentication after restricting the connection source IP address, set "Reject connection from outside the reception permitted network when using SMTP authentication". If you want to accept an arbitrary connection source IP address and perform SMTP authentication, set "do not reject connections from outside the network that allows reception when using SMTP authentication".

If you do not use "SMTP Authentication", only connections from authorized networks will be accepted.

SMTP authentication When using SMTP authentication
Accepted network
Connection from other
Operation Authentication target
Use Reject Accepts only the network that allows reception and performs SMTP authentication. Accepted network or SMTP authentication (*)
Use Do not reject Accept any connection source IP address and perform SMTP authentication. SMTP authentication
Do not use Accepts connections only for authorized networks and does not perform SMTP authentication. Accepted network
(*)If the mail relay source server does not use SMTP authentication, allow connection on the receiving permission network (connection source IP authentication).

Receive flow control

You can control the flow of mail received by the mail server using the maximum number of connections and the reception interval. Customers Mail Cloud causes an SMTP transaction to wait until the millisecond specified in the receive interval is reached after receiving one mail. As a result, even if burst traffic occurs, it is possible to control so that server resources such as CPU and memory are not used up.

The received flow rate is calculated by the following formula.

Email flow rate per hour= (3,600,000 ms / Reception interval ms) x Number of sessions x Number of IP

For example, if you want to limit the mail flow to 100,000 mails/hour, specify the maximum number of connections=10,and the reception interval=360. With this setting, the set value of mail flow will occur when the mail relay source server connects 10 SMTP sessions in parallel and sends mail continuously. If the number of parallel mail relay source servers is 5, the maximum number of connections=5 and the reception interval=180.
For emails with large content such as attachments, the SMTP transaction may not end within the reception interval. In this case, the calculated mail flow rate does not come out. If you want to increase the flow rate of mail per hour, instead of setting the reception interval extremely short,Increase the number of sessions (=increase the degree of parallelism).

Standard

The number of sessions=30 and the reception interval=360. The number of IPs is automatically adjusted to handle mail traffic properly.

Pro

If the number of sessions=30 and the reception interval=360 are set,settings can be changed. Reception performance can be scaled out by assigning multiple IPs.


Reception size control

The content size of the mail received from the mail relay source server has the following restrictions to protect the memory resources of the mail server.

Maximum settable reception size = 786,432KB (768MB) / Number of sessions

If the reception size is 20,480KB (20MB), the maximum number of sessions that can be set is 38.

Standard

In the Standard plan, the reception size is set to 20,480KB (20MB).


Saving the settings

The settings will be saved when the Save button is clicked or when the screen transitions to another setting screen (menu click, next button click, etc.) are saved.


Reflection the settings

This will be enabled when the saved settings reflected in mail server.After saving all the settings including other settings in the management console please doreflect settings in the mail server.