HOW-TO: Change Exim IP Address – cPanel

Change the IP exim uses to send mail – bypass sorbs (or other useless blacklists)

On shared hosting server’s you’ll probably find yourself blocked by other mail providers because of high mail volume or one of your users spamming. To change your exim IP for outgoing mail, you can edit your /etc/exim.conf file and locate this section:

remote_smtp:
driver = smtp

And below this add:

interface – xxx.xxx.xxx.xxx

Replace the x’s with the backup mail IP. Note that the backup mail IP needs to be added to the server, and should have a valid PTR and A-record.

Note:  On newer versions of cPanel where domainkeys are installed, you will need to add another interface line:

dk_remote_smtp:
driver = smtp
dk_private_key = “/var/cpanel/domain_keys/private/${dk_domain}”
dk_canon = nofws
dk_selector = default
interface = xxx.xxx.xxx.xxx

Now restart exim.

Note: If there is an exim update when you upgrade your cpanel server you will need to re-enter the interface again.

How to forward a website to another url using PHP

There are several ways to accomplish this task, but the simplest to understand is to use php.

To do this, you need to create the page that will do the forwarding. This can be any page, as long as it ends in “.php”. If you are trying to redirect a domain, you’d create “index.php” inside the public_html directory.

Once you decide which page you will use, then create the file and enter the following text:

<?php
header(“Location: http://whereyouwant.com/to/go.html“);
?>

Where http://whereyouwant.com/to/go.html is the location that you want the page to forward to. You can use local values, ie: /page.html, or full urls as in the above example (http://..etc.)

Apache : Showing files in a directory

Showing files in a directory
If you want to list all files in a directory that doesn’t use an index.html (or index.php) file, you can create an .htaccess file with the following contents:

Options +Indexes

This will tell apache that you want to list all files in the directory.

Securing CPanel

Running a WHM like Cpanel can sure make hosting easy, but unfortunately running a WHM often makes your server much less secure than it was before!

We do not guaranty that the following steps will make your server hack proof, but it will greatly reduce your chances of compromise. Also note that Layered Technologies does not manage your server and if you do not feel comfortable making system level changes to your server we recommend you open a level2 support ticket (for a fee) or hire a third party sysadmin service to help you.

Basic Steps to Securing CPanel (Linux based OS):

These are items inside of WHM/Cpanel that should be changed to secure your server.

Goto Server Setup =>> Tweak Settings

Check the following items…

Under Domains
Prevent users from parking/adding on common internet domains. (ie hotmail.com, aol.com)

Under Mail
Attempt to prevent pop3 connection floods
Default catch-all/default address behavior for new accounts – blackhole

Under System
Use jailshell as the default shell for all new accounts and modified accounts

Goto Server Setup =>> Tweak Security
Enable php open_basedir Protection
Enable mod_userdir Protection
Disabled Compilers for unprivileged users.

Goto Server Setup =>> Manage Wheel Group Users
Remove all users except for root and your main account from the wheel group.

Goto Server Setup =>> Shell Fork Bomb Protection
Enable Shell Fork Bomb/Memory Protection

When setting up Feature Limits for resellers in Resellers =>> Reseller Center, under Privileges always disable Allow Creation of Packages with Shell Access and enable Never allow creation of accounts with shell access; under Root Access disable All Features.

Goto Service Configuration =>> FTP Configuration
Disable Anonymous FTP

Goto Account Functions =>> Manage Shell Access
Disable Shell Access for all users (except yourself)

Goto Mysql =>> MySQL Root Password
Change root password for MySQL

Goto Security and run Quick Security Scan and Scan for Trojan Horses often. The following and similar items are not Trojans:
/sbin/depmod
/sbin/insmod
/sbin/insmod.static
/sbin/modinfo
/sbin/modprobe
/sbin/rmmod

These are measures that can be taken to secure your server, with SSH access.

Udate OS, Apache and CPanel to the latest stable versions.

This can be done from WHM/CPanel.

Restrict SSH Access

To restrict and secure SSH access, bind sshd to a single IP that is different than the main IP to the server, and on a different port than port 22.

SSH into server and login as root.

Note: You can download Putty by Clicking Here. It’s a clean running application that will not require installation on Windows-boxes.

At command prompt type: pico /etc/ssh/sshd_config

Scroll down to the section of the file that looks like this:
Code:

#Port 22
#Protocol 2, 1
#ListenAddress 0.0.0.0
#ListenAddress ::

Uncomment and change

#Port 22

to look like

Port 5678 (choose your own 4 to 5 digit port number (49151 is the highest port number)

Uncomment and change

#Protocol 2, 1

to look like

Protocol 2

Uncomment and change

#ListenAddress 0.0.0.0

to look like

ListenAddress 123.123.123.15 (use one of your own IP Addresses that has been assigned to your server)

Note 1: If you would like to disable direct Root Login, scroll down until you find

#PermitRootLogin yes

and uncomment it and make it look like

PermitRootLogin no

Save by pressing Ctrl o on your keyboard, and then exit by pressing Ctrl x on your keyboard.

Now restart SSH

At command prompt type: /etc/rc.d/init.d/sshd restart

Exit out of SSH, and then re-login to SSH using the new IP or nameserver, and the new port.

Disable Telnet

To disable telnet, SSH into server and login as root.

At command prompt type: pico -w /etc/xinetd.d/telnet

change disable = no to disable = yes

Save and Exit

At command prompt type: /etc/init.d/xinetd restart

Server e-mail everytime someone logs in as root

To have the server e-mail you everytime someone logs in as root, SSH into server and login as root.

At command prompt type: pico .bash_profile

Scroll down to the end of the file and add the following line:

echo ‘ALERT – Root Shell Access on:’ `date` `who` | mail -s “Alert: Root Access from `who | awk ‘{print $6}’`” your@email.com

Save and exit.

Set an SSH Legal Message

To an SSH legal message, SSH into server and login as root.

At command prompt type: pico /etc/motd

Enter your message, save and exit.

Note: I use the following message…
Code:

ALERT! You are entering a secured area! Your IP and login information
have been recorded. System administration has been notified.

This system is restricted to authorized access only. All activities on
this system are recorded and logged. Unauthorized access will be fully
investigated and reported to the appropriate law enforcement agencies.

Now everytime someone logs in, they will see this message… go ahead a try it.

Disable Shell Accounts

To disable any shell accounts hosted on your server SSH into server and login as root.

At command prompt type: locate shell.php

Also check for:

locate irc
locate eggdrop
locate bnc
locate BNC
locate ptlink
locate BitchX
locate guardservices
locate psyBNC
locate .rhosts

Note: There will be several listings that will be OS/CPanel related. Examples are

/home/cpapachebuild/buildapache/php-4.3.1/ext/ircg
/usr/local/cpanel/etc/sym/eggdrop.sym
/usr/local/cpanel/etc/sym/bnc.sym
/usr/local/cpanel/etc/sym/psyBNC.sym
/usr/local/cpanel/etc/sym/ptlink.sym
/usr/lib/libncurses.so
/usr/lib/libncurses.a
etc.

Disable identification output for Apache

To disable the version output for proftp, SSH into server and login as root.

At command prompt type: pico /etc/httpd/conf/httpd.conf

Scroll (way) down and change the following line to

ServerSignature Off

Restart Apache

At command prompt type: /etc/rc.d/init.d/httpd restart

These are applications that will help to secure your server.

Install chkrootkit

To install chrootkit, SSH into server and login as root.

At command prompt type: cd /root/

At command prompt type: wget ftp://ftp.pangeia.com.br/pub/seg/pac/chkrootkit.tar.gz

At command prompt type: tar xvzf chkrootkit.tar.gz

At command prompt type: cd chkrootkit-0.44

At command prompt type: make sense

To run chkrootkit

At command prompt type: /root/chkrootkit-0.44/chkrootkit

Make sure you run it on a regular basis, perhaps including it in a cron job.

Creating domain on a freshly added IP address fails in Parallels Panel for Windows

Symptoms
Creating domain with hosting on the IP address that has just been added fails and the following error is returned:

dnsmng::update() failed: dnsmng failed: Unknown error 0x80131501 (COM Error 80131501, Description: Generic failure ) at resetSecondaries ZoneName = '' transfer={ "" } notify={ "" }
at (dnsmng::msdns::MsDnsManager::resetSecondaries line 385)
at createPrimaryZone ZoneName = ''(dnsmng::msdns::MsDnsManager::createPrimaryZone line 373)
at execute "C:\Program Files (x86)\Parallels\Plesk\/admin/bin/dnsmng" update (vconsoleapp::run line 140)

Cause
As soon as an IP address is added to the system, Microsoft Windows performs the IP verification procedure, Windows checks up if the IP is unique. Until check-up is complete, the IP address is marked as ‘tentative’. If trying to create domain with physical hosting during the verification, creating DNS zone for the domain fails, which prevents from creating the domain.
Resolution
To avoid this issue, delay creating a domain for about 30 seconds after you add new IP address.

Parallels Power Panel show “Forbidden” error for all containers

Parallels Power Panel show “Forbidden” error for all containers,

APPLIES TO:
Virtuozzo Containers for Windows 4.0
Virtuozzo for Linux 3.x
Virtuozzo Containers for Windows 4.5
Virtuozzo Containers for Linux 4.0
Virtuozzo for Windows 3.5.1 SP1

Symptoms
The following error appears for all containers in the Parallels Power Panel:

Forbidden

The IP address of a physical server cannot be used with its Parallels Power Panel port number.

Do one of the following:

* If you want to open the Parallels Virtual Automation Control Center, use the IP address of the management server with the default port number.
* If you want to open the Parallels Power Panel, use the IP address or hostname of the Virtual Environment.

Cause
This issue may appear if the service container has no disk space remaining.

Resolution
To resolve this issue, users must find what has caused the lack of free disk space or increase the service container disk limit by the following command:

vzctl set 1 --diskspace 2000000 --save