Racker Hacker Words of wisdom from a server administrator

If you need to change to a different primary IP in Plesk, here’s the easiest way:
In Plesk 7 there is no concept of the Primary IP address for the server. From the Control panels point of view all IP addresses are equal. The only difference between the main IP address and aliases is that the [...]

To disable SSLv2 server-wide on a Plesk server, add this in your /etc/httpd/conf.d/ssl.conf:
SSLCipherSuite ALL:!ADH:!LOW:!SSLv2:!EXP:+HIGH:+MEDIUM
SSLProtocol all -SSLv2
Put the directive very high in the file, outside the VirtualHost directive, preferably right below the Listen directive. This will work for all SSL VirtualHosts.
How can I ensure that Apache does not allow SSL 2.0 protocol that has known [...]

To send e-mail properly to AOL and Hotmail, three things must match:

Your IP must have reverse DNS.
If you ask for the forward DNS record for the reverse, it must match.
Your mail server’s HELO must match the DNS records.

If you need to test your setup, use these commands.
$ host mhtx.net
mhtx.net has address 209.61.157.17
$ host 209.61.157.17
17.157.61.209.in-addr.arpa domain [...]

You can edit /etc/drweb/drweb_qmail.conf to eliminate receiving notification messages when Dr. Web has an issue:
[VirusNotifications]
SenderNotify = no
AdminNotify = no
RcptsNotify = no
Then just restart Dr. Web with:
/etc/init.d/drwebd restart
Plesk has a KB article about this issue as well.

If you want to hide the current version of Apache and your OS, just replace
ServerTokens OS
with
ServerTokens Prod
and restart Apache.