nmap - Network exploration tool and security / port scanner
Nmap (“Network Mapper”) is an open source tool for network exploration and security auditing. It was designed to rapidly scan large networks, although it works fine against single hosts. Nmap uses raw IP packets in novel ways to determine what hosts are available on the network, what services (application name and version) those hosts are offering, what operating systems (and OS versions) they are running, what type of packet filters/firewalls are in use, and dozens of other characteristics. While Nmap is commonly used for security audits, many systems and network administrators find it useful for routine tasks such as network inventory, managing service upgrade schedules, and monitoring host or service uptime.
A typical Nmap scan is shown in Example 1. The only Nmap arguments used in this example are -A, to enable OS and version detection,script scanning, and traceroute; -T4 for faster execution; and then the two target hostnames.
Example 1. A representative Nmap scan
# nmap -A -T4 scanme.nmap.org
How to Run Apache and lighthttpd on port 80
We need to have 2 IP in the server then only we can run both apache and lighthttpd on the same port. Assume that you have already installed both apache and lighthttpd in the server.
Lighthttpd will help to increase the speed with a small memory consumption.
Go to apache configuration and locate Listen directive.
Here, Add “Listen” directive to all IP addresses of the server, except the IP for lighthttpd.
Now, restart apache and then lighthttpd.
How to do this in WHM/cPanel.
Instead of modifying the file manually you need to exclude the IP address for lighttpd at
Main >> Service Configuration >> Apache Configuration >> Reserved IPs Editor
Reserved IPs Editor: By default, Apache is configured to listen on all available IPs. Apache can be configured to only respond on specific IPs. This editor provides an interface to specify the Apache IP restrictions. To reserve new IPs not found in this list, please add the IP to the server first.
You can try to access IP in browser and make sure both are listening on port 80.
Changing the SSH Port Number
To change the SSH port number login as root, and edit /etc/ssh/sshd_config
Find the line that says Port 22 and change 22 to any number between 1024->65535 (above 30000 is best) and save the file.
Once done, run:
Now start a new SSH session (don’t close your existing one), to make sure that you can get in.
-p port
Port to connect to on the remote host. This can be specified on a per-host basis in the configuration file.
Enable Alternate Port other than 25 or 587 (via SSH) in Plesk
Make a copy of /etc/xinetd.d/smtp_psa. For this walkthrough the new filename created is smtp_nonstandard. A command like this should work:
cp /etc/xinetd.d/smtp_psa /etc/xinetd.d/smtp_nonstandard
Add these lines to the copy you just made:
vi /etc/xinetd.d/smtp_nonstandard
type = UNLISTED
port = 2525
and change the service name to match the name of the file. A sample smtp_nonstandard looks like this:
service = smtp_nonstandard
type = UNLISTED
socket_type = stream
protocol = tcp
port = 2525
wait = no
disable = no
user = root
instances = UNLIMITED
server = /var/qmail/bin/tcp-env
server_args = -Rt0 /var/qmail/bin/relaylock /var/qmail/bin/qmail-smtpd /var/qmail/bin/smtp_auth /var/qmail/bin/true /var/qmail/bin/cmd5checkpw /var/qmail/bin/true
# Restart xinetd:
/etc/init.d/xinetd restart
# You should now be able to send mail through your server on port 2525. You may pick a different port if you use this method. We suggest choosing a high port number to avoid using commonly used ports on the internet.
How to change default 19368 port of control panel interface.
To change default 19638 port it is enough to change it in /etc/ensim/epl.conf file and restart epld service. In other configuration files it will be substituted accordingly.
Note that the sites configuration files are located in /etc/httpd/conf/virtual/ and include “RedirectMatch” directive that contain redirect to 19638 port.
