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server:mail [2020/07/01 14:58] grasshopperserver:mail [2022/01/17 19:43] – [Options] MUTE option is no longer used (replaced with semfile) digital man
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 The Synchronet Mail Server recognizes the incoming special address format: ''//<name>//#//<tag>//@//<host>//'' The Synchronet Mail Server recognizes the incoming special address format: ''//<name>//#//<tag>//@//<host>//''
  
-The //<tag>// is extracted from the address and if it is **not** found in the ''data/user/<usernum>.smtptags'' file, the mail message is +The //<tag>// is extracted from the address and if it is **not** found in the ''data/user/<usernum>.smtpblock'' file, the mail message is 
-sent to the destination user.  If the tag matches a line in the ''.smtptags'' file, the email is rejected by the mail server with a "no such user" error.+sent to the destination user.  If the tag matches a line in the ''.smtpblock'' file, the email is rejected by the mail server with a "no such user" error.
  
-This feature allows you (the sysop) to easily create and use "temporary" email addresses without requiring additional user accounts.  Once you start receiving spam with a tag, just disable that tag by adding it to your ''.smtptags'' file.+This feature allows you (the sysop) to easily create and use "temporary" email addresses without requiring additional user accounts.  Once you start receiving spam with a tag, just disable that tag by adding it to your ''.smtpblock'' file.
  
 ==== Anti-SPAM ==== ==== Anti-SPAM ====
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 ^ Key               ^ Default Value ^ Description ^ ^ Key               ^ Default Value ^ Description ^
-| Interface         | [global] Interface | Comma-separated list of IPv4 and IPv6 network interfaces to listen on for incoming SMTP/SMTPS connections | +| AutoStart         | true          | Automatically start up the server (manual is only supported in [[monitor:sbbsctrl]]) | 
-| POP3Interface     [global] Interface | Comma-separated list of IPv4 and IPv6 network interfaces to listen on for incoming POP3/POP3S connections | +| Interface         | [global]      | Comma-separated list of IPv4 and IPv6 network interfaces to listen on for incoming SMTP/SMTPS connections | 
-| OutboundInterface | 0.0.0.0       | IPv4 network interface to use for outgoing SMTP/SMTPS connections (0.0.0.0 = //any interface//) |+| POP3Interface     | Interface     | Comma-separated list of IPv4 and IPv6 network interfaces to listen on for incoming POP3/POP3S connections | 
 +| OutboundInterface | [global]      | IPv4 network interface to use for outgoing SMTP/SMTPS connections (0.0.0.0 = //any interface//) |
 | SMTPPort          | 25            | TCP port number to listen on for incoming SMTP mail-delivery connections | | SMTPPort          | 25            | TCP port number to listen on for incoming SMTP mail-delivery connections |
 | SubmissionPort    | 587           | TCP port number to listen on for incoming SMTP mail-submission connections | | SubmissionPort    | 587           | TCP port number to listen on for incoming SMTP mail-submission connections |
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 | TLSPOP3Port       | 995           | TCP port number to listen on for incoming POP3S (encrypted) mail-retrieval connections | | TLSPOP3Port       | 995           | TCP port number to listen on for incoming POP3S (encrypted) mail-retrieval connections |
 | MaxClients        | 10            | Maximum number of simultaneous incoming TCP sessions supported | | MaxClients        | 10            | Maximum number of simultaneous incoming TCP sessions supported |
 +| MaxConcurrentConnections | 0      | Maximum number of concurrent connections (without login) from the same IP address (0 = unlimited) |
 | MaxInactivity     | 120           | Maximum amount of TCP session inactivity before timeout and disconnection (in seconds) | | MaxInactivity     | 120           | Maximum amount of TCP session inactivity before timeout and disconnection (in seconds) |
 | MaxDeliveryAttempts | 50          | Maximum number of outbound mail delivery attempts before mail is bounced back to sender | | MaxDeliveryAttempts | 50          | Maximum number of outbound mail delivery attempts before mail is bounced back to sender |
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 | MaxMsgsWaiting        | 100       | Maximum number of messages allowed in a (non-W-exempt) user's inbox | | MaxMsgsWaiting        | 100       | Maximum number of messages allowed in a (non-W-exempt) user's inbox |
 | ConnectTimeout        | 30        | Timeout (in seconds) before blocked outbound SMTP/TCP connections are aborted | | ConnectTimeout        | 30        | Timeout (in seconds) before blocked outbound SMTP/TCP connections are aborted |
-| HostName              | [global] HostName  | Hostname of this server | +| HostName              | [global]  | Hostname of this server | 
-| TempDirectory         | [global] TempDirectory | Directory to use for the storage of temporary files |+| TempDirectory         | [global]  | Directory to use for the storage of temporary files |
 | RelayServer                     | Hostname or IP address of SMTP server to relay outbound mail through (requires ''RELAY_TX'' option) | | RelayServer                     | Hostname or IP address of SMTP server to relay outbound mail through (requires ''RELAY_TX'' option) |
 | RelayPort             | 25        | TCP port number to connect with when relaying mail to RelayServer | | RelayPort             | 25        | TCP port number to connect with when relaying mail to RelayServer |
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 | OutboundSound                   | WAV file to play upon outgoing SMTP/SMTPS connections (Windows only) | | OutboundSound                   | WAV file to play upon outgoing SMTP/SMTPS connections (Windows only) |
 | NewMailNotice         | "New e-mail from <%s>\r\n" | Format of telegram to send users upon receipt of incoming mail message | | NewMailNotice         | "New e-mail from <%s>\r\n" | Format of telegram to send users upon receipt of incoming mail message |
-| ForwardNotice         | "and it was forwarded to: %s | Additional telegram text to send to recipient of automatically forwarded mail | +| ForwardNotice         | "and it was forwarded to: %s| Additional telegram text to send to recipient of automatically forwarded mail | 
-| JavaScript*           | [global] JavaScript*    | JavaScript-related settings for external mail processing | +| JavaScript*           | [global]  | JavaScript-related settings for external mail processing | 
-| LogLevel              | [global] LogLevel*      | Minimum severity of log messages to be displayed / stored | +| LogLevel              | [global]  | Minimum severity of log messages to be displayed / stored | 
-| BindRetryCount        | [global] BindRetryCount | Maximum number of TCP port bind attempts before failure | +| BindRetryCount        | [global]  | Maximum number of TCP port bind attempts before failure | 
-| BindRetryDelay        | [global] BindRetryDelay | Delay (in seconds) between TCP port bind retries | +| BindRetryDelay        | [global]  | Delay (in seconds) between TCP port bind retries | 
-| LoginAttempt*         | [global] LoginAttempt*  | Failed login attempt throttling / filtering / banning |+| LoginAttempt*         | [global]  | Failed login attempt throttling / filtering / banning |
 | Options               | ''ALLOW_POP3'' | Mail server option flags (see below for details) | | Options               | ''ALLOW_POP3'' | Mail server option flags (see below for details) |
  
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 | NO_RECYCLE          | Do not allow this server to be automatically recycled by external event | | NO_RECYCLE          | Do not allow this server to be automatically recycled by external event |
 | KILL_READ_SPAM      | Mark received SPAM messages for "Kill after read" | | KILL_READ_SPAM      | Mark received SPAM messages for "Kill after read" |
-| MUTE                | Disable all sound (WAV) files from playing | 
  
-===== Email Security ===== 
- 
-In order to prevent one's emails from being labeled as SPAM, or worse, rejected. More and more Servers are starting to reject email that is not being secured to prove that it has come from a reliable source and not some spammer. This page will walk through the steps of securing your email server.  
- 
-//Note: This page assumes one owns a domain name and that domain name is the name to be used for one's BBS. If one uses synchro.net for emailing purposes, this will not apply in that case.// 
- 
-==== Dynamic IP Address - No problem ==== 
-  - Find a Dynamic Domain Server (DDNS) provider 
-    - There are many out there. There are even some free ones that will give at least one address which is all that is needed 
-    - This provider should provide directions on this initial setup 
-  - Setup an "A" record with whatever name is appropriate 
-    - This name won't be visible and serves as just a target for one's owned domain name to point to 
-  - Next step is to setup records on the owned Domain Name 
- 
-==== Domain Name Records Setup ==== 
-  - Log into one's provider of the domain name 
-  - Create an "A" record for the owned domain name 
-  - Create a "CNAME" record with the host name as one's BBS name or something else if prefered (i.e. this will be the address of one's BBS) 
-    - This should point to the address created in the DDNS provider 
-  - Create another "CNAME" record with the host name as 'mail' or some name that signifies it will be the name of the SMTP address 
-    - This should also point to the address created in the DDNS provider 
-  - Create a "MX" record and the host name should be the "@" symbol 
-    - This should point to the 'CNAME' in step 4 
-  - Next is to setup the "TXT" records that make the email being served more secure 
- 
-==== Creating the 'TXT' records for security ==== 
-  - Still logged into one's provider of the owned domain name, create a "TXT" record (i.e. This will be the SPF record) 
-    - The host name should be the "@" symbol 
-    - The TXT Value will contain the information that will state which domain names and IPs are OK if email comes from one of those. One will want to include all possible Domain Name/IP addresses that could serve up email. This part takes a little more effort to get the text right. Thankfully there are free tools available on the internet that will generate the SPF text for you. These are a couple of those sites. 
-      - https://www.spfwizard.net/ 
-      - https://www.dmarcanalyzer.com/spf/spf-record-generator/ (shows how to create an SPF record manually) 
-  - Create another "TXT" record (i.e. This will be the DMARC record) 
-    - The host name for this record has to be _dmarc 
-    - The value specifies where to send reports of abuse of one's domain name. 
-    - There is an online tool to help with the creation of the value of this record: 
-      - https://dmarcian.com/dmarc-record-wizard/ (there could be other's, this was just the first one I found) 
-  - Create yet another "TXT" record (this is the final one and it is the DKIM record) 
-    - This record will allow for the verification of the signage on the email that is placed by the MTA((Mail Transport Agent)) using a private key and the DKIM record has the public key. Thus emails can be verified against the DNS record. 
-    - **Note:** DKIM capabilities is currently __not__ available in Synchronet. 
-      - None-the-less, having the other records should help alleviate emails from being marked as junk/spam mail. 
- 
-=== Validation Check === 
-  * There are a couple of sites that can help with validating that the records are setup correctly: 
-    * https://mxtoolbox.com/MXLookup.aspx (Click the 'MX Lookup' button, then click the 'Find Problems' button) 
-    * https://www.dmarcanalyzer.com/spf/checker/ (under tools menu one can select dmarc also) 
-  * Check for any errors and correct them. If most every check turns up 'Green', then the records should be correct. 
-    * //Note: If your SPF record doesn't have an Domain Name/IP address that is used in delivering the email, the email will still be flagged as junk/spam// 
  
  
server/mail.txt · Last modified: 2024/03/04 18:30 by digital man
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