Step 1: A customer makes a connection to domain.com on an SSL port, typically 443. This connection is denoted with https instead of http.

Step 2: domain.com sends back its public key to the customer. Once customer receives it, his/her browser decides if it is alright to proceed.

• The domain.com public key must NOT be expired
• The domain.com public key must be for domain.com only
• The client must have the public key for Third Party SSL issuer, installed in their browser certificate store. 99.9% of all modern browsers (1998+) include the most of the Third Party SSL issuer’s  root certificate. If the customer has hird Party SSL issuer’s trusted public key, then they can trust that they are really communicating with Domain, Inc.

Step 3: If the customer decides to trust the certificate, then the customer will be sent to domain.com his/her public key.

Step 4: domain.com will next create a unique hash and encrypt it using both the customer’s public key and domain.com‘s private key, and send this back to the client.

Step 5: Customer’s browser will decrypt the hash. This process shows that the domain.com sent the hash and only the customer is able to read it.

Step 6: Customer and website can now securely exchange information.

You can upload multiple files uisng ‘lftp’ command.
steps:
lftp hostname
>user ftpusername ftppassword
> mirror source destination [To download entire directory]
> mirror -R source destination [To upload entire directory]

1. Top

The  top  program  provides a dynamic real-time view of a running system.  It can display system summary information as

well as a list of tasks currently being managed by the Linux kernel.  The types of system summary information shown and

the  types,  order  and size of information displayed for tasks are all user configurable and that configuration can be

made persistent across restarts.

The program provides a limited interactive interface for process manipulation as well as a much more  extensive  inter-

face for personal configuration  –  encompassing every aspect of its operation.  And while top is referred to through-

out this document, you are free to name the program anything you wish.  That new name, possibly an alias, will then  be

reflected on topâs display and used when reading and writing a configuration file.

2. Atop

The  program  atop  is  an interactive monitor to view the load on a Linux system.  It shows the occupation of the most

critical hardware resources (from a performance point of view) on system level, i.e. cpu, memory, disk and network.

It also shows which processes are responsible for the indicated load with respect to cpu- and memory  load  on  process

level.  Disk load is shown if per process “storage accounting” is active in the kernel or if the kernel patch âcntâ has

been installed.  Network load is only shown per process if the kernel patch has been installed.

3. Iftop

iftop listens to network traffic on a named interface, or on the first interface it can find which looks like an exter-

nal interface if none is specified, and displays a table of current bandwidth usage by pairs of hosts.  iftop  must  be

run  with sufficient permissions to monitor all network traffic on the interface, on most systems this means that it must be run as root.

By default, iftop will look up the hostnames associated with addresses it finds in packets. This can cause  substantial

traffic of itself, and may result in a confusing display. You may wish to suppress display of DNS traffic by using fil-

ter code such as not port domain, or switch it off entirely, by using the -n option or by pressing n when  the  program

is running.

By  default,  iftop  counts  all IP packets that pass through the filter, and the direction of the packet is determined

according to the direction the packet is moving across the interface.  Using the -F option it is possible to get  iftop

to  show  packets  entering and leaving a given network.  For example, iftop -F 10.0.0.0/255.0.0.0 will analyse packets

flowing in and out of the 10.* network

4. Mytop

mytop – display MySQL server performance info like `top’

In order for mytop to function properly, you must have the following:

* Perl 5.005 or newer

* Getopt::Long

* DBI and DBD::mysql

* Term::ReadKey from CPAN

Most systems are likely to have all of those installed–except for Term::ReadKey. You will need to pick that up from

the CPAN.

Enter into cpan shell and install the module

[root@dev-01 ~]# cpan

cpan> install Term::ReadKey

Install the packages using cpan shell interface

5. Htop

This program is a free (GPL) ncurses-based process viewer.

It  is  similar  to  top, but allows to scroll the list vertically and horizontally to see all processes and their full

command lines.

Tasks related to processes (killing, renicing) can be done without entering their PIDs

- Definition of a Fork bomb:

This is a bash function. It gets called recursively (recursive function).

This is often used by system administrators to test user processes limitations .Once a successful fork bomb has been activated in a system it may not be possible to resume back to normal operation without rebooting, as the only option to a fork bomb is to destroy all instances of it.

(more…)

Please make a copy of  configuration files before editing the same.

Steps:

Go to the following file and add the domain name.

/var/cpanel/maxemails

Eg: example.com = 1000

Just add an entry like “example.com = 1000 . Now 1000 will be the maximum email per hour limit for domain.

Execute the following script after updating the file /var/cpanel/maxemails, this will update the email settings in cpanel database.

#/scripts/build_maxemails_config