Domain

Overview

Every email account in hMailServer must belong to a domain. The domains specified in hMailServer can be local network domains or global internet domains such as hMailServer.com.

General

Domain name

The name of the domain. To be considered valid, a domain name must include a dot. You must set up your DNS servers so that email can be sent to your mail server.
 
IMPORTANT: When EDITING (renaming) an existing domain be aware that the process can take some time to complete and you will temporarily need double the disk space taken by the old domain data directory. This is due to the process actually creating a data directory for the new domain and then copying all email data from the old domain at operating system level before then deleting the old domain directory. Depending on the old domain data size and processor power, this copying could take many minutes. It is advised to restrict email use for the old domain whilst the copying of this data is taking place and to monitor for the process completion by watching for the old domain data directory to finally be deleted.

Names

One domain can have several names. These are also known as domain aliases. For example, your organization might own the domain, company.com, but it might also own company.org, company.se and company.de. If you want to be able to receive email for all these domains, you will have two options:
  1. Add all four domains to hMailServer. The problem with this is that you then have to add every email account 4 times, once for each domain.
  2. Add company.com as a domain, and then, under it, in the Names-tab, add company.org, company.se and company.de. That is, you add company.org, company.se and company.de as aliases of company.com. That, usually, is the route most users prefer.

If you set up a domain named example.com, and an alias named example.net, your server will accept email for both someone@example.com and someone@example.net. Your users will be able to log on as both someone@example.com and someone@example.net as well.

Creating a domain name alias

  1. Start hMailServer Administrator.
  2. Expand the Domains node and select the domain (e.g. mydomain.com).
  3. Select the Names tab.
  4. Add the domain names to the list (e.g. mydomain.org and mydomain.net)

Notes

  • You should not add the primary name (in our example, mydomain.com) to the list.
  • You can not add the same domain name aliases to multiple domains.

Signature

On the signature tab, you can configure hMailServer to add a signature to all email sent from this domain. It's possible to enter both a plain text version and a HTML version of the signature. If no HTML signature is specified, hMailServer will use the plain text signature as HTML signature as well.
 
Please note that the first two options, Add signatures to replies and Add signatures to local email applies both to domain signatures and account signatures. Even if you do not enable domain signatures, these two settings will have effect on account signatures.
  • Add signatures to replies
    If this option has been selected, hMailServer will add signature to replies. To determine whether a message is a reply, hMailServer checks for the In-Reply-To and the References header in the e-mail. This option is de-selected by default. Note that this option affects all email sent within the domain - not just domain signatures.
     
  • Add signatures to local email
    If you select this option, hMailServer will add signatures to local email. An email is considered local in this case if both the sender and all the recipients exist in the same domain. An email sent from one domain to another is not considered local, since the sender and recipient may not be aware of the fact that they both are hosted on the same server. Note that this option affects all email sent within the domain - not just domain signatures.
     
  • Enable domain signature
    If you select this option, the specified signature will be appended to email.

    • Use signature if none has been specified in the senders account.
      When selected, hMailServer will only use domain signature if an account signature has not been specified.
       
    • Overwrite account signature
      If you select this option, hMailServer will not use the account signatures for this domain. Instead, the domain signature will be used for all email.
       
    • Append to account signature
      When selected, hMailServer will append the account signature with the domain signature. This can be use if you for example want to add disclaimers to all outgoing email.
  • Plain text signature / HTML signature
    These two fields specify the domain signature to be used

It is possible to use the macros %User.FirstName% and %User.LastName% in signatures. These macros will be replaced with the users first and last name as specified in the account settings.

Limits

Maximum size (MB)

If this value has been specified (is not 0), the system administrator and the domain owner will be prevented from adding accounts so that the total size of all accounts exceeds this value. If you have specified 500MB, the total size of all messages in the domain will not exceed 500MB.

Maximum message size

If specified, hMailServer will reject messages larger than this size.
If not specified, the server-wide Max message size defined in the SMTP settings will be used.

Maximum size of accounts (MB)

If this value has been specified (is not 0), the server administrator and the domain owner will be prevented from adding accounts with a total size larger than this value.

Number of accounts, aliases and distribution lists

Using these settings, you can limit the number of accounts, aliases and distribution lists server administrators and domain owners can create in this domain.

DKIM signing 

DKIM, Domain Keys Identified Mail, is a method to sign the content of messages. The recipient can verify that the message is sent from a server authenticated to send from the sender's domain, and that the message content has not been modified in transit.

Before hMailServer delivers a message to another server, it will look at the sender address of the message. If the sender address matches a local domain, the DKIM signing options from that domain will be used. If DKIM signing has been enabled, the message will be signed.

Whether or not the original sender has used SMTP authentication when delivering the message to hMailServer has no effect on the DKIM signing process.

hMailServer only DKIM-signs email messages delivered to other servers. If a user on a hMailServer installation sends a message to another user on the same server, the message will not be signed.

Private key file

The private key to use when signing messages with DKIM. This must be a file existing on the local file system, readable by hMailServer, and the file must not have a password set.

Selector

This is the DKIM-selector to use for signing. To be able to use DKIM, you must specify a selector. The selector must be the same as the selector you are using for your DKIM record in your DNS server. For example, if your DNS record is named myselector._domainkey.example.net, you should enter "myselector" as selector (without quotes).

Header method

Choose between simple and relaxed canonicalization method. If you choose the simple canonicalization method, the signed headers of the message must not be modified at all. If a new line is added in an header the verification will fail. Choose the relaxed canonicalization method if you want to allow minor modifications to header li

Body method

Choose between simple and relaxed canonicalization method. If you choose the simple canonicalization method, the body of the message must not be modified at all. Choose the relaxed canonicalization method if you want to allow minor modifications to the body.

Signing method

Choose between the algorithms SHA1 and SHA256. SHA256 is encouraged since it gives higher security than SHA1. Senders of low-security messages such as newsletters may want to use SHA1 instead since it requires less CPU resources.

Advanced

This tab contains the advanced settings for the domain. You normally don't need to modify these settings.

Catch-all address

It is possible to specify an email address that receives all emails being sent to non-existent addresses on your domain. For example, you may have sales@mydomain.com, webmaster@mydomain.com and support@mydomain.com as existing accounts. But there's a risk that someone might misspell an email address, writing sails@mydomain.com instead of sales@mydomain.com.

The solution is to specify an account - either a previously existing one, or one created for the purpose - to be the catch-all account. All email sent to non-existent addresses on the domain will then be delivered to the catch-all account.

Example

  1. Start hMailAdmin
  2. Expand the Domains node and select the domain, say, mydomain.com
  3. Create a new account with the name catchall@mydomain.com
  4. Select your domain, and enter catchall@mydomain.com as catch-all address
  5. Save the changes

Notes

  • The catch-all address can be any email address you like. It does not have to be strictly of the form catchall@myDomain.com
  • The catch-all address does not have to belong to an account on your domain or even on hMailServer. You can forward messages to external servers.
  • If you want hMailServer to reject any messages sent to non-existent addresses in your domain, you should not specify a catch-all address.

Plus addressing

Use this option to enable plus addressing for this domain. To avoid confusion and configuration problems, only a limited set of characters are allowed for plus addresing.

Grey listing

Use this option to enable and disable grey listing for this domain.

 

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