Network Discovery using NMAP

Network Discovery using NMAP

Nmap is a network scanning and host detection tool that is very useful during several steps of penetration testing. It can be used for following purposes:

1. Detect the live host on the network.

2. Detect the open ports on the host.

3. Detect the software and the version to the respective port.

4. Detect the operating system, MAC address, software version etc.

Below are some commands to demonstrate the use of the NMAP.

# nmap ip/hostname

# nmap 10.14.153.31

The above command will show the information about the given host.

We can also specify the whole subnet for this purpose.

# nmap 10.14.153.0/24

Or

# nmap 10.14.153.142 10.14.153.212 10.14.153.25

We can also specify the range of IP address,

# nmap 10.14.153.10-100

We can also refer the hosts from a list of IPs.

# nmap –iL hosts.txt

Or

#nmap –sL hosts.txt

We can also use - - exclude option,

# nmap –sL 10.14.153.0/24 – exclude

We can specify the port number to scan them manually.

# nmap –p80,443,22 10.14.153.1-100

# nmap –sT 10.14.153.142

The above command can be used to check the open ports, the command will connect to every open port on the target machine and lists the open ports.

# nmap –sS 10.14.153.142

The above command is used to check open ports again, however the difference is that the T option will establish a real connection but S option will not make a full TCP connection to target machine. This type of scanning is logged to very less extent.

# nmap –sP 10.14.153.1/24

This is a simple ping scan to the complete network.

# nmap –PT80 10.14.153.5

This is an example for TCP ping scan.

RAID Concept

 

RAID CONCEPTS

How to calculate the various sizes after RAID implementations?

RAID 0(Stripe Set)

RAID 0 splits data across drives, resulting in higher data throughput. The performance of this configuration is extremely high, but a loss of any drive in the array will result in data loss. This level is commonly referred to as striping.




Space efficiency = 1 (100%)
Fault tolerance = 0 disk(s) (none)
Total Disks X Size of DISK = Total Size
Size after implementation = Total Size X Space Efficiency

Suppose we are using 3 disks of 250GB size, after RAID 0 implementation we get the total size out to be:

3 * 250 = 750
750 * 1 = 750

Hence we get 750 as final disk size.

RAID 1(Mirror)

RAID 1 writes all data to two or more drives for 100% redundancy: if either drive fails, no data is lost. Compared to a single drive, RAID 1 tends to be faster on reads, slower on writes. This is a good entry-level redundant configuration. However, since an entire drive is a duplicate, the cost per megabyte is high. This is commonly referred to as mirroring.



Space efficiency = 0.5 (50%)
Fault tolerance = 1 disk(s)
Total Disks X Size of DISK = Total Size
Size after implementation = Total Size X Space Efficiency

Suppose we are using 3 disks of 250GB size, after RAID 1 implementation we get the total size out to be:

3 * 250 = 750
750 * 0.5 = 375

Hence we get 375 as final disk size.

RAID 5

RAID 5 stripes data at a block level across several drives, with parity equality distributed among the drives. The parity information allows recovery from the failure of any single drive. Write performance is rather quick, but because parity data must be skipped on each drive during reads, reads are slower. The low ratio of parity to data means low redundancy overhead.




Space efficiency = 0.666666666666667 (66.6666666666667%)
Fault tolerance = 1 disk(s)
Total Disks X Size of DISK = Total Size
Size after implementation = Total Size X Space Efficiency

Suppose we are using 3 disks of 250GB size, after RAID 5 implementation we get the total size out to be:

3 * 250 = 750
750 * 0.667 = 500

Hence we get 500 as final disk size.

RAID 6

RAID 6 is an upgrade from RAID 5: data is striped at a block level across several drives with double parity distributed among the drives. As in RAID 5, parity information allows recovery from the failure of any single drive. The double parity gives RAID 6 additional redundancy at the cost of lower write performance (read performance is the same), and redundancy overhead remains low.




Space efficiency = 0.5 (50%)
Fault tolerance = 2 disk(s)
Total Disks X Size of DISK = Total Size
Size after implementation = Total Size X Space Efficiency

Suppose we are using 4 disks of 250GB size, after RAID 6 implementation we get the total size out to be:

4 * 250 = 1000
1000 * 0.5 = 500

Hence we get 500 as final disk size.

RAID 10

RAID 10 is a striped (RAID 0) array whose segments are mirrored (RAID 1). RAID 10 is a popular configuration for environments where high performance and security are required. In terms of performance it is similar to RAID 0+1. However, it has superior fault tolerance and rebuild performance.




Space efficiency = 0.5 (50%)
Fault tolerance = 1 disk (min) to 2 disks (max)
Total Disks X Size of DISK = Total Size
Size after implementation = Total Size X Space Efficiency

Suppose we are using 4 disks of 250GB size, after RAID 10 implementation we get the total size out to be:

4 * 250 = 1000
1000 * 0.5 = 500

Hence we get 500 as final disk size.

RAID 50

RAID 50 combines RAID 5 parity and stripes it as in a RAID 0 configuration. Although high in cost and complexity, performance and fault tolerance are superior to RAID 5.

RAID 60

RAID 60 combines RAID 6 double parity and stripes it as in a RAID 0 configuration. Although high in cost and complexity, performance and fault tolerance are superior to RAID 6.




RAID 01

RAID 0+1 is a mirror (RAID 1) array whose segments are striped (RAID 0) arrays. This configuration combines the security of RAID 1 with an extra performance boost from the RAID 0 striping.

What to do when you have deleted /etc/fstab file from Linux and rebooted the server?

/etc/fstab is one of the most critical file in the Linux system. It contains the filesystem tables and information of the mount points. We need this file information at the time of reboot. Partition information is required to mount / partition and other partition table. When this is deleted or missed, our PC will definitely ran into some problem. But we can rather save our PC, if we miss our file.

This blog will tell how to recover from a missing /etc/fstab file.

When you rebooted the server without the /etc/fstab file, we will get some error on the screen on the booting time. But it is important to debug if it is really a fstab error or something else.
For this we have to know the boot process also. As we know that the fstab information is required by the kernel at the time of the reboot. So you will see BIOS is loading, MBR is loading and then GrUB loaded successfully but after that at the time of kernel starting the services, we will ran to an error screen.

Read the error carefully, as the error itself gives the detailed description of the problem. It will say, filesystem table is missing or /etc/fstab not found etc.

At this stage, you know that the error is related to the filesystem table.

This problem can be resolved by a number of ways. We will discuss them one by one.

1. By creating the required file in single user mode.
2. By booting the system in rescue mode and then creating the file.


1. Using single user mode.

1. Reboot the server.
2. Press e when kernel listing is there on the grub screen, add 1 to the kernel parameters to boot the system in single user mode.
3. When the server boots into single user mode, check the UUID using command, blkid as shown in the snapshot.
# blkid
4. Now try to create the file /etc/fstab using vi. But you will not be able to create the file as the server is mounted in the read only mode. So remount the server in rw mode again.
# mount -o loop rw,remount /dev/sda2 /
5. Now create file /etc/fstab and write all the mount points required to boot the server.

6. Unmount the / again and reboot the server. The server will surely boot and come up.


2. Using Rescue Mode.

1. Reboot the server using a rescue CD or bootable media.
2. When menu appears for installation from CD, select from menu the rescue the previous installation.
3. Follow the instruction and it will finally give a command prompt.
4. Try mounting the / partition on /tmp or /mnt of your server in read write mode using above method.
5. After that follow the same above procedure and create /etc/fstab file on the server. If we don't want to go in all this mess, you can also copy the file /proc/mounts to /etc/fstab.
# cat /proc/mounts > /etc/fstab
6. This option will let you reboot the server next time, but your filesystem may or may not be mounted at this time. So after rebooting the server you can mannually add the partition information and then reboot the server.

Domain Name Server - A Simple Name Resolving Model

DNS (Domain Name System), also known as a nameserver, is a network system that associates hostnames with their respective IP addresses. For users, this has the advantage that they can refer to machines on the network by names that are usually easier to remember than the numerical network addresses called IPs. For system administrators, using the nameserver allows them to change the IP address for a host without ever affecting the name-based queries, or to decide which machines handle these queries.


DNS is usually implemented using one or more centralized servers that are authoritative for certain domains. When a client host requests information from a nameserver, it usually connects to port 53. The nameserver then attempts to resolve the name requested. If it does not have an authoritative answer, or does not already have the answer cached from an earlier query, it queries other nameservers, called root nameservers, to determine which nameservers are authoritative for the name in question, and then queries them to get the requested name. Nameserver Zones:In a DNS server such as BIND (Berkeley Internet Name Domain), all information is stored in basic data elements called resource records (RR). The resource record is usually a fully qualified domain name (FQDN) of a host, and is broken down into multiple sections organized into a tree-like hierarchy. This hierarchy consists of a main trunk, primary branches, secondary branches, and so on.Here is a simple guide to install DNS on RHEL6. Consider a fresh installation of redhat enterprise linux on a machine, to make it simple.BIND consists of a set of DNS-related programs. It contains a nameserver called named, an administration utility called rndc, and a debugging tool called dig.


Note the following:


Host machine IP Address: 10.14.153.24

Hostname: desktop24.example.com


Make following enteries in the following files:


# vim /etc/resolv.conf


nameserver 10.14.153.24

search example.com


# vim /etc/hosts
10.14.153.24 desktop24.example.com desktop24

127.0.0.1 localhost.localdomain localhost


Make sure to assign static IP address to the machine.First check the Ethernet LAN port on which the machine is connected using following commands:


# mii-tools# ethtool eth0


After that edit the network file:


# vim /etc/sysconfig/network-scripts/ifcfg-eth0


DEVICE=eth0

TYPE=Ethernet

BOOTPROTO=static

ONBOOT=yes

IPADDR=10.14.153.24

NETMASK=255.255.255.0

GATEWAY=10.14.153.1


save and quit


Now stop the service of NetworkManager and restart the service of network.


# /etc/init.d/NetworkManager stop;chkconfig NetworkManager off

#/etc/init.d/network restart;chkconfig network on


Now, make sure YUM is working on your machine.

Install the following packages on the machine using YUM.

# yum install -y bind*
When installation is completed, we proceed with the configuration,main configuration files are:

/etc/named/named.conf

/var/named/chroot/etc/named.conf

also we need to include some files, we discuss about them later.Edit the configuration file as:

# vim /var/named/chroot/etc/named.conf

//
// named.conf
//
// Provided by Red Hat bind package to configure the ISC BIND named(8) DNS
// server as a caching only nameserver (as a localhost DNS resolver only).
//
// See /usr/share/doc/bind*/sample/ for example named configuration files.
//

options {
        listen-on port 53 { 127.0.0.1;10.14.153.24; };
        listen-on-v6 port 53 { ::1; };
        directory       "/var/named";
        dump-file       "/var/named/data/cache_dump.db";
        statistics-file "/var/named/data/named_stats.txt";
        memstatistics-file "/var/named/data/named_mem_stats.txt";
        allow-query     { localhost; };
        recursion yes;

        dnssec-enable yes;
        dnssec-validation yes;
        dnssec-lookaside auto;

        /* Path to ISC DLV key */
        bindkeys-file "/etc/named.iscdlv.key";
};

logging {
        channel default_debug {
                file "data/named.run";
                severity dynamic;
        };
};

zone "." IN {
        type hint;
        file "named.ca";
};

zone "example.com" IN {
        type master;
        file "forward.zone";
        allow-update { none; };
};
zone "153.14.10.in-addr.arpa" IN {
        type master;
        file "reverse.zone";
        allow-update { none; };
};

Save and quit the file.

Write only the above lines in the file, if you don't know how to customize DNS.
Also create the new files that you have added in the above file:
# vim /var/named/chroot/var/named/forward.zone
$TTL 1D
@       IN SOA  desktop24.example.com. root.desktop24.example.com. (
                                        0       ; serial
                                        1D      ; refresh
                                        1H      ; retry
                                        1W      ; expire
                                        3H )    ; minimum
        NS      desktop24.example.com.
desktop24       A       10.14.153.24

desktop23       A       10.14.153.23

save and quit.

# vim /var/named/chroot/var/named/reverse.zone
$TTL 3H
@       IN SOA  desktop24.example.com. root.desktop24.example.com. (
                                        0       ; serial
                                        1D      ; refresh
                                        1H      ; retry
                                        1W      ; expire
                                        3H )    ; minimum
        NS      desktop24.example.com.
24      PTR     desktop24.

Save and quit.


Make sure that the firewall and SELinux is off, also the owner ship of the above two files is as:

# cd /var/named/chroot/var/named/

# chown root.named reverse.zone

# chown root.named forward.zone

These lines may be at any sequence.
Now restart the service and send query to the DNS.

# /etc/init.d/named restart;chkconfig named on
Stopping named:                                            [  OK  ]
Starting named:                                            [  OK  ]

[root@desktop24 ~]# nslookup desktop24.example.com

Server:         10.14.153.24

Address:        10.14.153.24#53

Name:   desktop24.example.com

Address: 10.14.153.24

[root@desktop24 ~]# dig desktop24.example.com

; <<>> DiG 9.7.0-P2-RedHat-9.7.0-5.P2.el6 <<>> desktop24.example.com

;; global options: +cmd

;; Got answer:

;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 22786

;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 1, ADDITIONAL: 0

;; QUESTION SECTION:

;desktop24.example.com.         IN      A

;; ANSWER SECTION:

desktop24.example.com.  86400   IN      A       10.14.153.24

;; AUTHORITY SECTION:

example.com.            86400   IN      NS      desktop24.example.com.

;; Query time: 0 msec

;; SERVER: 10.14.153.24#53(10.14.153.24)

;; WHEN: Sat Oct  4 05:18:13 2014

;; MSG SIZE  rcvd: 69

[root@desktop24 ~]# dig desktop23.example.com

; <<>> DiG 9.7.0-P2-RedHat-9.7.0-5.P2.el6 <<>> desktop23.example.com
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 14385
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 1, ADDITIONAL: 1

;; QUESTION SECTION:
;desktop23.example.com.         IN      A

;; ANSWER SECTION:
desktop23.example.com.  86400   IN      A       10.14.153.23

;; AUTHORITY SECTION:
example.com.            86400   IN      NS      desktop24.example.com.

;; ADDITIONAL SECTION:
desktop24.example.com.  86400   IN      A       10.14.153.24

;; Query time: 0 msec
;; SERVER: 10.14.153.24#53(10.14.153.24)
;; WHEN: Sat Oct  4 05:19:32 2014
;; MSG SIZE  rcvd: 95

If some reply is received, means your dns is resolving.

save and quit.

Mail Server Configuration with courier-imap on RHEL5

This is simple doc to install Mail server on RHEL 5 with courier-imap.

1. First of  all install rhel5 on the system.

2. Copy the Server directory from ISO/CD to the location:

/var/www/html/

#rsync –avz /media/RHEL_5.6/Server /var/www/html/Server/

3. Create yum on the freshly created system.

# vim /etc/yum.repos.d/server.repo

[server]

name=test

baseurl=file:///var/www/html/Server/

esc :wq

4. Now install the following packages using yum.

# yum install *mysql* *php* *rpm* *http* *system-sw* -y

5. Download postfixadmin-2.2.1.1.tar.gz.

6. [root@mail~] # mkdir /var/www/html/mailadmin

7. [root@mail~] # cp Dosktop/postfixadmin-2.2.1.1.tar.gz /var/www/html/

8. [root@mail html] # tar -zxf /postfixadmin-2.2.1.1.tar.gz

9. [root@mail postfixadmin-2.2.1.1] # cp config.inc.php config.inc.php-org 

10. [root@mail postfixadmin-2.2.1.1]# vi config.inc.php

$CONF['database_type'] = 'mysql';

$CONF['database_host'] = 'localhost';

$CONF['database_user'] = 'postfix';

$CONF['database_password'] = 'postfix';

$CONF['database_name'] = 'postfix';

$CONF['admin_email'] = 'postmaster@iic.com';

$CONF['encrypt'] = 'cleartext';

// Default Aliases

// The default aliases that need to be created for all domains.

$CONF['default_aliases'] = array (

    'abuse' => 'abuse@fooster.com',

    'hostmaster' => 'hostmaster@iic.com',

    'postmaster' => 'postmaster@iic.com',

    'webmaster' => 'webmaster@iic.com'

$CONF['domain_path'] = 'YES';

$CONF['domain_in_mailbox'] = 'YES';

$CONF['vacation_domain'] = 'autoreply.change-this-toyour.domain.tld';

$CONF['show_footer_text'] = 'YES';

$CONF['footer_text'] = 'www.dell.com';

$CONF['footer_link'] = 'www.dell.com';

CONF['emailcheck_resolve_domain']='YES'; 

11. [root@mail html]# mv  postfixadmin-2.2.1.1 mailadmin

12. [root@mail mailadmin]# service httpd restart

13. [root@mail mailadmin]# service mysqld  restart

14. [root@mail html]# mysqladmin password "postfix" (set password database user)

15. [root@mail html]# mysql -u root -p

Enter password:   

  mysql>

  mysql> CREATE DATABASE postfix; 

  mysql> CREATE USER 'postfix'@'localhost' IDENTIFIED BY 'postfix';

  mysql>  GRANT ALL PRIVILEGES ON `postfix` . * TO 'postfix'@'localhost';

  mysql> show databases;

+--------------------+

| Database           |

+--------------------+

| information_schema |

| mysql              |

| postfix            |

| test               |

+--------------------+

4 rows in set (0.00 sec) 

mysql> quit

16. [root@mail mailadmin]# /etc/init.d/httpd restart

17.  Now open web-browser and enter the following address.

http://localhost/mailadmin

18.  Click on the SETUP link on the page opened.

19. [root@mail mailadmin]# vim config.inc.php 

$CONF['configured'] = false;  

20. Now add the account of the super user at the end and rename the setup.php file in mailadmin/.

21. [root@mail mailadmin]# mv setup.php setup.php-org

22. [root@mail mailadmin]# service httpd restart 

23.  Create a new user, to build the rpms.

 

# useradd rpmbuild

# passwd rpmbuild

24.  Download the source rpm from internet and copy to home directory of user.

# cp Desktop/postfix-2.5.5-1.src.rpm /home/rpmbuild/

# chown rpmbuild.rpmbuild /home/rpmbuild/postfix-2.5.5-1.src.rpm

25.  Now switch to new user and create following directory set:

# su - rpmbuild

[rpmbuild@mail ~]$ mkdir rpm

[rpmbuild@mail ~]$  mkdir rpm/SOURCES

[rpmbuild@mail ~]$  mkdir rpm/SPECS

[rpmbuild@mail ~]$  mkdir rpm/BUILD

[rpmbuild@mail ~]$  mkdir rpm/SRPMS

[rpmbuild@mail ~]$  mkdir rpm/RPMS

[rpmbuild@mail ~]$  mkdir rpm/RPMS/x86_64

[rpmbuild@mail ~]$  echo "%_topdir    $HOME/rpm" >> $HOME/.rpmmacros

26.  Now install the source RPM that was downloaded.

[rpmbuild@mail ~]$  rpm -ivh postfix-2.5.5-1.src.rpm

27.  Now edit the postfix.spec file, that is automatically created under rpm/SPECS/

[rpmbuild@mail ~]$ cd rpm/SPECS

[rpmbuild@mail SPECS]$ ls

   postfix.spec

[rpmbuild@mail SPECS]$ vim postfix.spec

%define with_mysql_redhat 1

    %define with_sasl         2

    %define with_vda       1 

{Replace every occurrence of rhel4 with rhel5 in the file.}

28.  Now build the rpm using RPMBUILD.

[rampal@mail SPECS]$ rpmbuild -ba postfix.spec 

29. This will create rpms on following locations:

/home/rampal/rpm/RPMS/i386/postfix-2.5.5-1.rhel5.i386.rpm

/home/rampal/rpm/RPMS/i386/postfix-debuginfo-2.5.5-1.rhel5.i386.rpm 

[rampal@mail SPECS]$  logout 

30.  Install these packages as root.

[root@mail i386]# rpm -Uvh postfix-2.5.5-1.rhel5.i386.rpm

[root@mail i386]# rpm -Uvh postfix-debuginfo-2.5.5-1.rhel5.i386.rpm  

[root@mail i386]# postconf -m    

      btree

      cidr

      environ

      hash

      ldap

      mysql

      nis

      proxy

      regexp

      static

      unix

31.  Download courier-imap-4.4.1.tar.bz2 from internet and copy this to home directory of the user. Change the user ownership of the file.

32. Also download  the file courier-authlib-0.61.0.tar.bz2 and copy this file also to the home directory of the user, also change the ownership.

[root@mail Desktop]# cp courier-imap-4.1.1.tar.bz2 /home/rampal/

[root@mail Desktop]# chown rampal.rampal /home/rampal/courier-imap-4.1.1.tar.bz2  

[root@mail Desktop]# cp courier-authlib-0.58.tar.bz2 /home/rampal/

[root@mail Desktop]# chown rampal.rampal /home/rampal/courier-authlib-0.58.tar.bz2

33.  Now switch to user and build the rpm using rpmbuild.

[root@mail Desktop]# su - rampal

[rampal@mail ~]$  rpmbuild -ta  courier-authlib-0.58.tar.bz2

[rampal@mail~]$ logout

34.  Install the dependencies of the rpmbuild as the root user using yum.

[root@mail Desktop]# yum install *libtool*

[root@mail Desktop]# yum install *postgresql-devel*

[root@mail Desktop]# yum install *gdbm-devel*

[root@mail Desktop]# yum install *pam-devel

[root@mail Desktop]# yum install *expect*

[root@mail Desktop]# yum install *gcc-c++*

[root@mail Desktop]# su - rampal

[rampal@mail ~]$  rpmbuild -ta  courier-authlib-0.58.tar.bz2

[rampal@mail~]$ logout

35.  Now packages are created on the following location. Install these packages.

[root@mail ~]$ cd /home/rampal/rpm/RPMS/i386/

[root@mail i386]$ rpm -ivh courier-authlib-0.58-1.5Server.i386.rpm

[root@mail i368]$ rpm -ivh  courier-authlib-debuginfo-0.58-1.5Server.i386.rpm

[root@mail i386]$ rpm -ivh courier-authlib-devel-0.58-1.5Server.i386.rpm

[root@mail i386]$ rpm -ivh  courier-authlib-ldap-0.58-1.5Server.i386.rpm

[root@mail i386]$ rpm -ivh courier-authlib-mysql-0.58-1.5Server.i386.rpm

[root@mail i386]$ rpm -ivh courier-authlib-pgsql-0.58-1.5Server.i386.rpm

[root@mail i386]$ rpm -ivh courier-authlib-pipe-0.58-1.5Server.i386.rpm

[root@mail i386]$ rpm -ivh courier-authlib-userdb-0.58-1.5Server.i386.rpm

[root@mail ~]# su - rampal

36.  Now untar the courier-imap file , make following changes in the file and copy it to rpm/SPEC/ location.

[rampal@mail ~]$  tar -jxvf courier-imap-4.1.1.tar.bz2

[rampal@mail ~]$ cd courier-imap-4.1.1

[rampal@mail courier-imap-4.1.1]$ cp courier-imap.spec courier-imap.spec-org

[rampal@mail courier-imap-4.1.1]$ vi courier-imap.spec  

BuildPreReq: rpm >= 3.0.5 /usr/bin/sed openldap2 openldap2-devel

%else

BuildPreReq: rpm >= 4.0.2 sed openldap-devel openldap-servers

%endif

{remove every thing except these in the above lines in the file}

37.  Now run the rpmbuild command to build the rpm packages. If it shows some dependencies, install those dependencies using yum as root. When the command completes building packages, install those packages as root.

[rampal@mail] courier-imap-4.1.1]$  cp courier-imap.spec /home/rampal/rpm/SPECS/

[rampal@mail]courier-imap-4.1.1]$  cp courier-imap-4.1.1.tar.bz2 /home/rampal/rpm/SOURCES

[rampal@mail~]$  cd rpm/SPECS/

[rampal@mail] SPECS]$ rpmbuild -ba courier-imap.spec

    dependencies: openldap* rpm

[ramapl@mail~] logout

[root@mail~]# yum install  openldap*

[root@mail~]# su - rampal

[rampal@mail] SPECS]$ rpmbuild -ba courier-imap.spec

[rampal@mail] SPECS]$ logout

[root@mail ~] cd /home/rampal/rpm/RPMS/i386/

[root@mail i386]# rpm -ivh courier-imap-4.1.1-1.5Server.i386.rpm

[root@mail i386]# rpm -ivh courier-imap-debuginfo-4.1.1-1.5Server.i386.rpm

38.  Now add a virtual user with uid=1001 and gid=1001.

[root@mail ~]#  useradd virtual ( useradd only virtual uid-1001 gid-1001)

[root@mail ~]# passwd virtual 

virtual:x:1001:1001::/home/virtual:/bin/bash 

[root@mail ~]# vi /etc/passwd 

virtual:x:1001: 

[root@mail ~]# vi /etc/group 

[root@mail ~]# chmod -R 777 /home/virtual/

[root@mail ~]# chown virtual.virtual /home/virtual 

39.  Now copy the main.cf file to a temp file and make following changes in the file.

[root@mail postfix]# cp /etc/postfix/main.cf main.cf_org

[root@mail postfix]#  vi /etc/postfix/main.cf 

Add these line in the end of file : 

virtual_alias_maps = mysql:/etc/postfix/mysql_virtual_alias_maps.cf

virtual_gid_maps = static:1001

virtual_mailbox_base = /home/virtual

virtual_mailbox_domains = mysql:/etc/postfix/mysql_virtual_domains_maps.cf

virtual_mailbox_limit = 51200000

virtual_mailbox_maps = mysql:/etc/postfix/mysql_virtual_mailbox_maps.cf

virtual_minimum_uid = 1001

virtual_transport = virtual

virtual_uid_maps = static:1001

#Additional for quota support

virtual_create_maildirsize = yes

virtual_mailbox_extended = yes

virtual_mailbox_limit_maps = mysql:/etc/postfix/mysql_virtual_mailbox_limit_maps.cf

virtual_mailbox_limit_override = yes

virtual_maildir_limit_message = Sorry, the user's maildir has overdrawn his diskspace quota,   please try again later.

virtual_overquota_bounce = yes

relay_domains = mysql:/etc/postfix/mysql_relay_domains_maps.cf

mynetworks = 192.168.0.0/24, 127.0.0.0/8 

[root@mail postfix]#  postmap hash:/etc/postfix/aliases

[root@mail postfix]#  service postfix restart 

40.  Add following files in the /etc/postfix directory:

[root@mail ~]# vi /etc/postfix/mysql_relay_domains_maps.cf

user = postfix

password = postfix

hosts = localhost

dbname = postfix

query = SELECT domain FROM domain WHERE domain='%s' and backupmx = '1' 

[root@mail ~]# vi /etc/postfix/mysql_virtual_mailbox_limit_maps.cf

user = postfix

password = postfix

hosts = localhost

dbname = postfix

query = SELECT quota FROM mailbox WHERE username='%s' 

[root@mail ~]# vi /etc/postfix/mysql_virtual_alias_maps.cf

user = postfix

password = postfix

hosts = localhost

dbname = postfix

query = SELECT goto FROM alias WHERE address='%s' AND active = 1 

[root@mail ~]# vi /etc/postfix/mysql_virtual_mailbox_maps.cf

user = postfix

password = postfix

hosts = localhost

dbname = postfix

query = SELECT maildir FROM mailbox WHERE username='%s' AND active = 1 

#  [root@mail~]# vi /etc/postfix/mysql_virtual_domains_maps.cf

user = postfix

password = postfix

hosts = localhost

dbname = postfix

query = SELECT domain FROM domain WHERE domain='%s'

#optional query to use when relaying for backup MX

#query = SELECT domain FROM domain WHERE domain='%s' and backupmx = '0' and active = '1' 

41.  Also make changes in following files:

/etc/authlib/authmysqlrc:

[root@mail ~]# cd /etc/authlib/

[root@mail authlib]#  cp authmysqlrc authmysqlrc_org

[root@mail authlib]# vi authmysqlrc ( This file authentusen file mysql and database 

MYSQL_SERVER            localhost

MYSQL_USERNAME          postfix

MYSQL_PASSWORD          postfix

MYSQL_PORT              0

MYSQL_OPT               0

MYSQL_DATABASE          postfix

MYSQL_USER_TABLE        mailbox

#MYSQL_CRYPT_PWFILED     crypt

MYSQL_CLEAR_PWFIELD     password

MYSQL_UID_FIELD         1001

MYSQL_GID_FIELD         1001

MYSQL_LOGIN_FIELD       username

MYSQL_HOME_FIELD        '/home/virtual'

MYSQL_NAME_FIELD        name

MYSQL_MAILDIR_FIELD     maildir 

[root@mail ~]# vim /etc/authlib/authdaemonrc  

authmodulelist=" authmysql "

[root@mail ~]# /etc/init.d/courier-authlib restart

[root@mail ~]# /etc/init.d/courier-imap restart

[root@mail ~]# /etc/init.d/httpd restart

42.  Open web-browser and open following url:

http://localhost/mailadmin/

login email = user name@domain name

password=  ******

43.  Now you can add new mailbox, domains and send mails to user from your server.