Q: Email
is resolving very slowly on my virtual server. What can I do to improve its
performance?
A: Check the mail queue, located in your /usr/spool/mqueue
directory, using the following command:
ll ~/usr/spool/mqueue
You may see a display such as:
total 3
-rw------- 1 username vuser 1676 Nov 4 00:18 dfAAA19297
-rw------- 1 username vuser 4090 Nov 2 01:33 dfBAA01360
-rw------- 1 username vuser 532 Nov 4 02:48 dfCAA13672
When you send an email, one of three things can happen:
1) It can resolve to a mailbox and be successfully received by that mailbox so
that its owner can download it at a later time.
2) It can bounce because the address does not resolve to a mailbox, or the
mailbox is not accepting email (usually because it is full or the server is
filtering email).
3) Finally, it can be "spooled" or "queued" in your /usr/spool/mqueue
directory.
The /usr/spool/mqueue directory contains any email which has not been sent or
received successfully by your virtual server. There are a variety of reasons
why this can happen. If you send an email to a server with which a connection
is currently not possible; or if the email resolution for a domain is not
clear; or if load on either the sending or receiving server is too high to
handle emails - then the server will queue the email, and try to resolve it
again at a later time.
By default, most mail servers attempt to send a queued message every five
hours; however, your virtual server is set to try every 30 minutes. Automated
settings do not always work as well as attempting to manually clear the queue,
however, and if you find many emails in this directory, you can attempt the
virtual sendmail –q command.
The mail queue is designed to only keep messages for five days, after which
time if the message has not resolved, it will be bounced back to the sender.
Q: I
can receive email, but I often receive timeout errors when I try to send.
A: Check the pophash file in your ~/etc
directory, using the following command:
wc ~/etc/pophash
You may see a display such as:
479 958 8902 /usr/home/username/etc/pophash
With PopAuth installed, every time you or one of your users checks email, the
IP address is added to the pophash database, which is then used for verifying
a valid user when sending. Anyone coming from an IP address in the pophash
file is then able to send email through your virtual server, and every time
you or one of your users attempts to send email, this file is checked to make
certain the IP address is present. When you run wc ~/etc/pophash, the first
number display, in this case "479" is the number of lines in the
file, where there is one IP address per line. If there are hundreds, or even
thousands of IP addresses to check, the longer it will take to send, and the
greater the chance that your connection will time out.
You can also place this command in your cron file, with a line such as:
0 3 * * * vcleandb > /dev/null
This line will clear your pophash database at 3:00 a.m. every day (server
time),
The second part of the command, "> /dev/null" is simply to
prevent the cron task from emailing you every time it runs to let you know it
was successful. Once you have cleared the pophash database, you will need to
check email again before sending.
Q: When
trying to send email, I receive "No Socket Error" from my email
program.
A: Your ISP may be blocking outgoing
traffic on port 25.
Some dialup providers use this method to prevent spam, by keeping anyone with
their service from using an outside mail server to send email. You will want
to contact your dialup provider to find out if this is the case. However, if
this is occurring, you can either use a different ISP connection when sending
email.
Q: How
many email accounts can I host on my virtual server?
A: There is no limit to the number of
POP3 accounts you can create. Realistically, however, you will run into limits
in terms of account administration, since the accounts will be hosted on your
server and therefore will take up space for the incoming mail. We recommend
allocating 5 MB per account
Q: Why
are there so many emails sitting in my mail server's ~/usr/spool/mqueue
directory, waiting to be sent?
A: There are many reasons why ~/usr/spool/mqueue
may fill with messages.
If sendmail is temporarily unavailable (because of excessive server activity,
for example), messages will queue in ~/usr/spool/mqueue until such time as
sendmail can handle the messages.
Although sendmail will handle the messages on its own, you can force sendmail
to process the mail queue by entering the virtual sendmail -q command at your
mail server's Telnet/SSH prompt.
If the destination email server is temporarily unavailable, or if there are
other errors with an email message, the message may be deferred and remain in
~/usr/spool/mqueue until it can be sent.
To check for errors or to find out why a message has not been sent, type the
virtual sendmail -q –v command at your mail server's Telnet/SSH prompt. This
command will process the mail queue in verbose mode, so you can see any errors
or other messages arising from sendmail.
Finally, you can safely delete any file that is over five days old, as
sendmail will stop trying to send a message after five days of not being able
to reach the destination mail server.
Q: How
can I change the full name of the administrative account on my Virtual
Server?
A: Warning: This FAQ entry applies to the
250 meg above ONLY. If you attempt this on a Virtual Server 100 meg or
smaller, it will strip the FTP privileges for your administrative account.
To change the full name of the administrative account on your virtual server,
follow these steps:
1) Log into the VAdmin Web interface by directing your URL to: http://yourdomain.com/vadmin.
Please note, to access VAdmin you are required to have the login name and
password of your administrative account.
2) Select the User Manager tab.
3) Select the administrative account.
4) Enter the new full name for the administrative account.
5) Click Update to complete the change.
Q: When
trying to send email attachments I receive errors. Any ideas on what I can
do to correct this?
A: You may be attempting to download
a file attachment too large for your mail to handle. Email was never designed
for file transfer, and therefore doesn't accomplish this efficiently. If you
would like to send a large file to someone, we would recommend uploading it to
your Virtual Server and making it available for download through HTTP or FTP.
Remember there will be at least two copies of any file attachments. If
your virtual server does not have enough extra space to hold two copies of an
email, it cannot be delivered, and if your virtual server does not have enough
extra space to hold two copies of your mailbox, you cannot download the mail.
Q: How
do I setup my virtual server to page my pager whenever I get an email?
A: NOTE: This FAQ assumes that your
paging provider provides email service for your pager. If you do not know your
pager's email address, simply call your paging provider and ask them if they
provide this service to you.
It is easy to setup your virtual server to page you whenever you get an email.
Simply follow the steps below:
1) Create a generic account on your virtual server using the vadduser command.
2) Name the account something like 'user1' or 'pageme' or whatever you want.
3) Edit your ~/etc/aliases file, and add the alias you want everyone to use.
Example: Suppose your name is Jim and you have jim@mydomain.com set up. You
would then have jim point to your user account, and to your pager's email
address like so:
jim: user1,5555555@mobile.att.net
4) Exit your aliases file and run the vnewaliases command to make the changes
take effect.
Email
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