How to Easily Pass the RedHat RH302 Exam: Expert Advice

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 allowedto 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:

1.vi /etc/vsftpd/ftpusers

user1

user2

2.service vsftpd start| restart

Using /etc/vsftpd/ftpusers file we can deny to certain users to access files via ftp. As wellas there is another file named /etc/vsftpd.user_list can be used to allow or to deny to users.

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

hosts allow=192.168.0.

[data]

path=/data

writable=yes

public=no

browsable=yes

2.service smb start| restart

3.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 to 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.

To allow access the shared directory only from certain network or hosts, there is a option hosts allow= host or network. If this option is applied on global option, then it will apply to all shared directory.

Do the following steps as:

1.vi /etc/httpd/conf/httpd.conf

ServerNamewww.abc.com

DocumentRoot /var/www/abc/

AllowOverrideauthconfig

DirectoryIndexindex.html

ServerAdminwebmaster@abc.com

ErrorLog logs/error_abc.logs

CustomLog logs/custom_abc.logs common

2.Create the directory and index page on specified path. (Index page can download fromftp://server1.example.comat exam time)

Check the SELinux context of index.html file, should be 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

3.vi /var/www/abc/.htaccess

AuthName“Only to Authorized Users”

AuthTypebasic

AuthUserFile/etc/httpd/conf/mypasswd

requirevalid-user

Check the SELinux Context, should like this:

-rw-r--r-- root root root:object_r:httpd_sys_content_t .htaccess

htpasswd –c /etc/httpd/conf/mypasswd user5

htpasswd –m /etc/httpd/conf/mypasswd user6

chgrp apache /etc/httpd/conf/mypasswd

chmod g+r /etc/httpd/conf/mypasswd

Check the SELinux Context, should like this:

-rw-r--r-- root root system_u:object_r:httpd_config_t /etc/httpd/conf/mypasswd

Use restorecon command to restore the mismatched SELinux Context of the file.

service httpd restart

chkconfig httpd on

AllowOverride Authconfig is used to specify which and how much configuration can be overridden by directory specific .htaccess files.

One of the most common tasks performed in users’ .htaccess files is adding authorization. Typically, a user will setup authorization for directories that hold sensitive information with a configuration.

Do the following steps as:

1.vi /etc/samba/smb.conf

[global]

netbios name=station?

workgroup=station?

security=user

smb passwd file=/etc/samba/smbpasswd

encrypt passwords=yes

hosts allow= .example.com

[data]

path=/storage

public=no

writable=no

write list=harold

browsable=yes

2.smbpasswd -a harold

3.service smb start

4.chkconfig smb on

/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/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.

At exam Lab example.com domain resides on 172.24.0.0/16 Network and my133t.org resides on 172.25.0.0/16 Network.

1.vi /etc/squid/squid.conf

#detault:

http_port8080

#Recommended minimum configuration:

# Near the src acl src section

acl allownet src 172.24.0.0/255.255.0.0

acl denynet src 172.25.0.0/255.255.0.0

#Default:

# http_access deny all

#Under Herehttp_access allow allownet

http_access deny denynet

2.service squid start

3.chkconfig squid on

squid is a proxy caching server, using squid we can share the internet, block the internet, to certain network. First we should define the port for squid, the standard port for squid is 3128. We can run squid on different port by specifying http_port portnumber.

Do the following steps as:

1.vi /etc/samba/smb.conf

[global]

netbios name=station?

workgroup=linuxgroup

security=share

printcap name=/etc/printcap

load printers=yes

printing=cups

[printers]

path=/var/spool/samba

browsable=yes

printable=yes

guest ok=no

writable=no

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 to share the user’s home directory.

/etc/printcap file contains all installed printers name. Printing is print system used on server.

Do the following steps as:

1.vi /etc/hosts.deny

dovecot:ALL EXCEPT .example.com EXCEPT station20.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.

Outside the LAN means my133t.org. All host on exam on example.com domain and outside domain means cracker.org.

To block the mail coming from cracker.org

1.vi /etc/mail/access

@my133t.orgREJECT

2.service sendmail start | restart

3.chkconfig sendmail on