Once you have installed a mail server, you have to manage email accounts actively, and users may require substantial technical support. You will also need to be very careful to keep the server up and running--many people rely on their email servers even more than their web sites.
For background, see Server Administration Responsibilities , and RFC1173: Responsibilities of Host and Network Mangers .
You will have to create and maintain accounts, explain the differences between accounts and email addresses, reset passwords when users forget them, help with login and email client problems, and so on. For more information on this, see Account Tips and Examples .
We recommend that you inform your users that their email is not private, that you can see the senders and recipients in the log, and that you can change their password and log into their account at any time. Make sure they understand your rules, especially if you do not allow private messages to be sent via a company server.
In more serious situations, email users on your host may be sending spam or threats. In those cases, your Terms of Service agreement (if you are an ISP) or company policy on email use should clarify what behavior you will and will not accept.
See also: Dealing With Spam (Unsolicited Email) .
You must have and read a "Postmaster" account that accepts mail to the postmaster address at all email hosts. This account will get messages from other mail administrators, other mail servers which have received messages with problems in the headers, confused people looking for someone in your company, and so on.
You can forward postmaster mail to another email address. For details on configuring a forwarding address, see Forward To .
You must read these messages frequently, at least five times a week, as some of them will be urgent and require immediate attention. For example, if one of your users is sending unsolicited messages or their system has been infected by an email attachment virus, and someone sends a message to this account, they will expect you to act right away. If you are unable to read messages to this account, because you are on vacation or otherwise inaccessible, be sure to arrange for someone else to read the messages in the Postmaster account.
When incoming mail is not accepted due to insufficient disk space, or when automatic backups fail for any reason, the Mail server will send a message to the Postmaster account. That's another reason to make sure you check mail for this account frequently.
When messages come to the server for accounts that do not exist in the specified host, they will be forwarded to the account that you have specified to accept mail for unknown accounts for that host. This can be the Postmaster address, or another address. These messages will be a mix of legitimate messages sent by mistake, spam and other junk.
See Unknown Address .
In any case, be sure that someone reads and handles these messages, either by answering them, returning them to the sender, forwarding to the appropriate person, or deleting them (if they are spam or other unwanted messages).
As a mail administrator, you must track the activity of your server. If you have a busy server and many users, you should check the server often and make sure that messages are moving properly, that you have enough disk space, and so on. For servers with few accounts, you can just check once a day or even less often.
You should use the WebSTAR Admin Mail Monitor to track your mail server activity. If your server is very busy, you may see the Connections bars fill up. In that case, you should use the Mail Connections to add more connections to your most overloaded protocols. You should also quit the server and allocate more RAM to WebSTAR, unless you have a lot of free memory.
See Server Administration Responsibilities .
Mail server reports show you how many messages and how much data is flowing through your server. You can see how many SMTP messages come in and go out of your mail hosts, and activity of each individual user on your server. You can get Mail server reports daily, weekly or monthly (see Setting the Report Schedule ). This tells you if a particular host or account is extremely busy: then you may want to mandate reduced use of the server, increase WebSTAR's memory allocation, or move a mail host to another server.
For information and examples, see Reporting
When you look at the mail queue, you'll see all the messages that could not be sent because the receiving SMTP server was not responding. Messages will stay in the queue until the receiving server appears or the undeliverable mail period passes, in which case, the server returns the message to the sender.
To set this period, see Hold Undeliverable Mail .
Tracking disk space is very important. Email can fill up a disk very quickly with messages and attachments, especially if you have many IMAP accounts and allow users to store messages and files on the server. Servers can also fill up when users go on vacation, suddenly start sending large graphics or binary files, or subscribe to active mailing lists, adding many entries to the mail log files.
To set limits on how much space a user can have see Mail Storage .
All messages are saved in the WebSTAR Mail Users file, and the attachments are in the Attachments folder. The server always keeps two backup copies, and requires swap space to make a new backup before deleting the old one. For example, if your current WebSTAR Mail Users file takes up 25 MB, your next backups will also take that much room, and you need at least 25 MB free space on the disk for the copy process.
You should check the server disk space regularly, to make sure there is free space. Track the rate of disk space usage to make sure you check it often enough.
For example, if you have a server with 10 users and 500 MB of free space, if you notice that the disk is filling up a the rate of 5 MB per week, you can check disk space weekly. On the other hand, if you have 100 users, 500 MB of free space, and the disk is filling up at 50 MB per week, you may want to check the space daily (and implement a storage limit for some or all users).
Mail logs provide detailed information about logins, incoming and outgoing messages, connection errors, and forgotten passwords. You can use these logs to identify patterns of problems such as routing errors or attempts to break into accounts by guessing passwords. In addition, you can inspect the log to decide if one of your users is sending messages to many recipients at once, which may be considered spam.
For information see Activity Log .
The most important file to back up is WebSTAR Mail Users. It stores the messages as well as the user information.
WebSTAR automatically keeps two backup copies: WebSTAR Mail Users Backup.1 and WebSTAR Mail Users Backup.2. It will automatically delete the older backup after successfully making a new copy.
If something happens to the WebSTAR Mail Users file, the server will automatically recreate it, with all the previous email messages and account information. It does this by comparing the Backup files and the Transaction Log and rebuilding the users file based upon that data.
It's always a good idea to keep external backups of your email files. You should be prepared for a hard drive crash, a server machine failure or a physical disaster such as a fire in the building. Be sure that you store backups offsite frequently, so that you can re-create your mail system in an emergency.
Unsolicited messages, whether for business, political or other purposes, is a serious problem on the Internet. This email, known as spam , wastes the time and money of the recipients, especially those who must pay for their Internet connection by the minute or second. Therefore, all mail administrators should keep their servers from participating in spam mailings. In addition, if your server sends out spam, it may be blacklisted --registered as a spammer by a spam-checking service--and all messages from your server will be rejected by other mail servers who use that service.
There are three ways your server might become involved in spam mailings.
If you allow your server to be a relay server (to forward messages from other servers without restriction), your server will probably be used without your consent to send spam.
To avoid this, always check the Require Prior Client Login box in the Mail Setting panel Mail Connections . This will require users to check mail before sending messages, proving that they are in fact legitimate users.
Your users may be convinced that sending unsolicited email is acceptable, and start sending spam. You can check this in your log file to see whether this account has sent many messages to large numbers of recipients. In that case, you may need to invoke your Terms of Service agreement and remove the account from your server. Again, you should do this before your server is blacklisted.
A few pieces of unwanted email should not be cause for alarm, but some users get on lists and start getting dozens of spam messages a week or even every day. In that case, you can use Mail Allow/Deny to reject messages from the host names or IP addresses of the most blatant spammers.
In addition, services such as spamcop.net will help you track down and remove spam accounts.