Do the following steps as:

1. vi /etc/samba/smb.conf

[global]

netbios name=station?

workgroup = mygroup

server string=Share from Linux Server

security=user

smb passwd file=/etc/samba/smbpasswd

encrypt passwords=yes

[data]

path=/data

writable=no

public=no

browsable=yes

write list= user1 user2

2. smbpasswd –a user1

3. smbpasswd –a user2

……..

4. service smb start | restart

5. chkconfig smb on

Samba servers helps to share the data between linux and windows. Configuration file is /etc/samba/smb.conf. There are some pre-defined section, i. global  use to define the global options, ii. Printers  use to share the printers, iii. homes  use the share the user’s home directory.

Security=user  validation by samba username and password. May be there are other users also. To allow certain share to certain user we should use valid users option.

smbpasswd  Helps to change user’s smb password. –a option specifies that the username following should be added to the local smbpasswd file.

If any valid users option is not specified, then all samba users can access the shared data. By Default shared permission is on writable=no means read only sharing. Write list option is used to allow write access on shared directory to certain users or group members.

Do the following steps as:

1. vi /etc/httpd/conf.d/ssl.conf

< VirtualHost 192.100.0.2 >

ServerName www.rhce.com

DocumentRoot /var/www/rhce

DirectoryIndex index.html index.htm

ServerAdmin webmaster@rhce.com

SSLEngine on

SSLCertificateFile /etc/pki/tls/certs/localhost.crt

SSLCertificateKeyFile /etc/pki/tls/private/localhost.key

< /VirtualHost >

2. cd /etc/httpd/conf

3. make testcert

4. Create the directory and index page on specified path. (Index page can download from ftp://server1.example.com at exam time)

Check the SELinux context of index page , should like this:

-rw-r--r-- root root system_u:object_r:httpd_sys_content_t /var/www/html/index.html

If SELinux Context is mismatched, use the restorecon –R /var command

5. service httpd start|restart

6. chkconfig httpd on

Apache can provide encrypted communications using SSL (Secure Socket Layer). To make use of encrypted communication, a client must request to https protocol, which is uses port 443. For HTTPS protocol required the certificate file and key file.

Do the following steps as:

1. vi /etc/hosts.deny

sshd:ALL EXCEPT .example.com

or

1. vi /etc/hosts.deny

sshd:ALL

2. vi /etc/hosts.allow

sshd:.example.com

We can secure the services using tcp_wrappers. There are main two files, /etc/hosts.allow and /etc/hosts.deny.

There will be three stage access checking

- Is access explicitly permitted? Means permitted from /etc/hosts.allow?

- Otherwise, Is access explicitly denied? Means denied from /etc/hosts.deny?

- Otherwise, by default permit access if neither condition matched.

To deny the services we can configure /etc/hosts.deny file using ALL and EXCEPT operation. Pattern of /etc/hosts.allow and /etc/hosts.deny file is:

Demon_list:client_list:options

In Client list can be either domain name or IP address.

Do the following steps as:

vi /etc/mail/virtusertable

@cracker.org eric

service sendmail restart

/etc/mail/virtusertable file is used to send the mail coming for virtual user to real user. According to question, all mail to cracker.org should get by eric user so

@cracker.org eric : Which sends all mail of cracker.org to eric user.

Do the following steps as:

1. vi /etc/hosts.deny

vsftpd:ALL EXCEPT .example.com

or

1. vi /etc/hosts.deny

vsftpd:ALL

2. vi /etc/hosts.allow

vsftpd:.example.com

We can secure the services using tcp_wrappers. There are main two files, /etc/hosts.allow and /etc/hosts.deny.

There will be three stage access checking

- Is access explicitly permitted? Means permitted from /etc/hosts.allow?

- Otherwise, Is access explicitly denied? Means denied from /etc/hosts.deny?

- Otherwise, by default permit access if neither condition matched.

To deny the services we can configure /etc/hosts.deny file using ALL and EXCEPT operation. Pattern of /etc/hosts.allow and /etc/hosts.deny file is:

Demon_list:client_list:options

In Client list can be either domain name or IP address.

Do the following steps as:

1. vi /etc/vsftpd/vsftpd.conf

anon_upload_enable=yes

chown_uploads=yes

chown_username=username

2. service vsftpd start| restart

3. directory owner should be ftp user: chown ftp directory path allowed to upload files.

4. Write permission should be set to owner user.

By default anonymous user can only download files from the ftp. Should write anon_upload_enable=yes to enable anonymous upload files. Default Directory for anonymous is /var/ftp.

Do the following steps as:

useradd username

passwd username

usermod -e “date”

example: usermod -e “12 Feb 2006” user4

Verify: chage –l user4

Questions asking you to install the dialog package from the server. In your Lab FTP server as well as NFS server are configured. You can install either through FTP or NFS.

1. Just Login to server1.example.com through FTP: ftp server1.example.com

2. Enter to pub directory: cd pub

3. Enter to RedHat/RPMS: cd RedHat/RPMS

4. Download the Package: mget dialog-*

5. Logout from the FTP server: bye

6. Install the package: rpm -ivh dialog-*

7. Verify the package either installed or not: rpm -q dialog

Do the following steps as:

usermod -G training user1

usermod -G training user2

usermod -G training user3

Verify from : cat /etc/group

There are two types of group, I) primary group II) Secondary or supplementary group.

Primary Group: Primary group defines the files/directories and process owner group there can be only one primary group of one user.

Secondary Group is used for permission. Where permission are defined for group members, user can access by belonging to that group.

Here user1, user2 and user3 belong as supplementary to training group. So these users get the permission of group member.

Do the following steps as:

1. useradd jane

2. useradd john

useradd command is used to create the user. All user’s information stores in /etc/passwd and user;s shadow password stores in /etc/shadow.