What is Squid web server?and Configure squid web proxy server.

This summary is not available. Please <a href="http://ipv4-ipv6.blogspot.com/2013/11/what-is-squid-web-serverand-configure.html"> click here </a> to view the post.

What is Squid web server?and Configure squid web proxy server.

Tukiyooo 0 09:28

This summary is not available. Please click here to view the post.… Read more »

Read more »

What is Samba? Configure samba server.

<div dir="ltr" style="text-align: left;" trbidi="on">What is Samba? <br />Samba is a software package that gives network administrators flexibility and freedom in terms of setup, configuration, and choice of systems and equipment. Because of all that it offers, Samba has grown in popularity, and continues to do so, every year since its release in 1992.<br /><br />Most Linux systems are the part of networks that also run Windows systems. Using Linux <strong> Samba servers</strong>, your Linux and Windows systems can share directories and printers. This is most use full situation where your clients are window native and you want to use the linux security features.<br /><strong> Exam question</strong> There are mixed lots of System running on Linux and Windows OS. Some users are working on Windows Operating System. There is a <strong> /data</strong> directory on linux server should make available on windows to only vinita should have right to connect with samba server . Configure to make available.<br /><br /><div class="title"><b>Example 1.1. A minimal smb.conf</b></div><div class="example-contents"><table border="0" class="simplelist" summary="Simple list"><tbody><tr><td> </td></tr><tr><td><em class="parameter"><code>[global]</code></em></td></tr><tr><td><a class="indexterm" href="http://www.blogger.com/null" name="id2552290"></a><em class="parameter"><code>workgroup = WKG</code></em></td></tr><tr><td><a class="indexterm" href="http://www.blogger.com/null" name="id2552301"></a><em class="parameter"><code>netbios name = MYNAME</code></em></td></tr><tr><td> </td></tr><tr><td><em class="parameter"><code>[share1]</code></em></td></tr><tr><td><a class="indexterm" href="http://www.blogger.com/null" name="id2552320"></a><em class="parameter"><code>path = /tmp</code></em></td></tr><tr><td> </td></tr><tr><td><em class="parameter"><code>[share2]</code></em></td></tr><tr><td><a class="indexterm" href="http://www.blogger.com/null" name="id2552338"></a><em class="parameter"><code>path = /my_shared_folder</code></em></td></tr><tr><td><a class="indexterm" href="http://www.blogger.com/null" name="id2552349"></a><em class="parameter"><code>comment = Some random files</code></em></td></tr></tbody></table></div><h3>Configure samba server</h3>In this example we will configure a <strong> samba</strong> server and will transfer files from client side.For this example we are using two systems one linux server one window clients.<br />per quest of samba server<br /><ul class="ul_star"><li>A linux server with ip address 192.168.0.254 and hostname Server</li><li>A window client with ip address 192.168.0.2 and hostname Client2</li><li>Updated /etc/hosts file on linux system</li><li>Running portmap and xinetd services</li><li>Firewall should be off on server</li></ul>We have configured all these steps in our pervious article.<br />We suggest you to review that article before start configuration of samba server. Once you have completed the necessary steps follow this guide.<br /><strong> samba</strong> rpm is required to configure samba server. check them if not found then install<br /> <img alt="rpm for samba server" border="0" class="padded s5_lazyload" height="84" src="http://computernetworkingnotes.com/images/rhce_certification/image/ass36_rpm.jpg" style="opacity: 1;" width="291" /><br />Now check <strong> smb, portmap, xinetd</strong> service in system service it should be on<br /><div class="code"><pre> #setup Select <strong> System service</strong> from list<br /> [*]portmap<br /> [*]xinetd<br /> [*]smb</pre></div>Now restart <strong> xinetd</strong> and <strong> portmap</strong> and <strong> smb</strong> service<br /> <img alt="service restart" border="0" class="padded s5_lazyload" height="119" src="http://computernetworkingnotes.com/images/rhce_certification/image/ass24_service_restart.jpg" style="opacity: 1;" width="607" /><br /> To keep on these services after reboot on then via <strong> chkconfig</strong> command<br /> <img alt="chkconfig" border="0" class="padded s5_lazyload" height="55" src="http://computernetworkingnotes.com/images/rhce_certification/image/ass24_chkconfig.jpg" style="opacity: 1;" width="337" /><br /> After reboot verify their status. It must be in running condition<br /> <img alt="service status" border="0" class="padded s5_lazyload" height="84" src="http://computernetworkingnotes.com/images/rhce_certification/image/ass24_service_status.jpg" style="opacity: 1;" width="354" /><br />Create a normal user named<strong> vinita</strong> <br /> <img alt="useradd" border="0" class="padded s5_lazyload" height="129" src="http://computernetworkingnotes.com/images/rhce_certification/image/useradd_vinita.jpg" style="opacity: 1;" width="495" /><br />now create <strong> /data</strong> directory and grant it <strong> full permission</strong> <br /> <img alt="mkdir" border="0" class="padded s5_lazyload" height="56" src="http://computernetworkingnotes.com/images/rhce_certification/image/ass36_mkdir_data.jpg" style="opacity: 1;" width="299" /><br />open <strong> /etc/samba/smb.conf</strong> main samba configuration files <br /> <img alt="vi smb.conf" border="0" class="padded s5_lazyload" height="21" src="http://computernetworkingnotes.com/images/rhce_certification/image/ass36_vi_smb.jpg" style="opacity: 1;" width="380" /><br /> By default name of workgroup is <strong> MYGROUP</strong> in <strong> smb.conf</strong> file. you can change it with desire name <br /> <img alt="workgroup tag" border="0" class="padded s5_lazyload" height="91" src="http://computernetworkingnotes.com/images/rhce_certification/image/ass36_smb_file_workgroup.jpg" style="opacity: 1;" width="437" /><br /> our task is to share <strong> data</strong> folder for <strong> vinita</strong> user so go in the end of file and do editing as shown here in this image <br /> <img alt="share data folder in smb.conf" border="0" class="padded s5_lazyload" height="159" src="http://computernetworkingnotes.com/images/rhce_certification/image/ass36_share_data_smb.jpg" style="opacity: 1;" width="241" /><br /> save file with <strong> :wq</strong> and exit<br />Now add vinita user to <strong> samba user</strong><br /> <img alt="smbpasswd" border="0" class="padded s5_lazyload" height="69" src="http://computernetworkingnotes.com/images/rhce_certification/image/ass36_smbpasswd.jpg" style="opacity: 1;" width="328" /><br /> we have made necessary change now on <strong> smb service</strong> and check it status <br /> <img alt="service smb status" border="0" class="padded s5_lazyload" height="132" src="http://computernetworkingnotes.com/images/rhce_certification/image/ass36_service_status.jpg" style="opacity: 1;" width="324" /><br /> if you already have on this service then restart it with <strong> service smb restart</strong> commands.<br /><h3>Client configuration for samba server</h3>Go on windows system and <strong> ping</strong> samba server, change computer name to <strong> client2</strong> and workgroup name to <strong> MYGROUP</strong> <br /> <img alt="my computer properties" border="0" class="padded s5_lazyload" height="389" src="http://computernetworkingnotes.com/images/rhce_certification/image/ass36_my_computer_pro.jpg" style="opacity: 1;" width="316" /><br /> <strong> reboot</strong> system after changing workgroup name<br />After reboot open my network place here you can see <strong> samba server</strong> [ if not see then click on view workgroup computer in right pane, if still not see then use search button from tool bar and search computer samba server form ip ]<br /> <img alt="samba server in my network place" border="0" class="padded s5_lazyload" height="98" src="http://computernetworkingnotes.com/images/rhce_certification/image/ass36_win_show_samba.jpg" style="opacity: 1;" width="221" /><br /> First try to login from user <strong> nikita</strong> she will not successes as nikita have not permission to login <br /> <img alt="user nikita deny" border="0" class="padded s5_lazyload" height="217" src="http://computernetworkingnotes.com/images/rhce_certification/image/ass36_nikita_deny.jpg" style="opacity: 1;" width="267" /><br /> Now login from user <strong> vinita</strong> [ give the password which you set with <strong> smbpasswd</strong> command ]<br /><img alt="user vinita" border="0" class="padded s5_lazyload" height="259" src="http://computernetworkingnotes.com/images/rhce_certification/image/ass36_vinita_login.jpg" style="opacity: 1;" width="350" /><br />As you can see in image user vinita gets the <strong> /data</strong> folder which we share from <strong> samba server</strong> <br /> <img alt="data folder on widow" border="0" class="padded s5_lazyload" height="221" src="http://computernetworkingnotes.com/images/rhce_certification/image/ass36_win_data_folder.jpg" style="opacity: 1;" width="531" /><br /> Copy some window files in <strong> data</strong> folder <br /> <img alt="copy in data folder" border="0" class="padded s5_lazyload" height="189" src="http://computernetworkingnotes.com/images/rhce_certification/image/ass36_copy_in_data.jpg" style="opacity: 1;" width="383" /><br /><div class="custom"><div class="link_text_laybord"> <ins style="background-color: transparent; border: none; display: inline-table; height: 15px; margin: 0; padding: 0; position: relative; visibility: visible; width: 728px;"><ins id="aswift_3_anchor" style="background-color: transparent; border: none; display: block; height: 15px; margin: 0; padding: 0; position: relative; visibility: visible; width: 728px;"></ins></ins> </div></div><h3>Check status on samba server</h3>on <strong> samba server</strong> you can check runtime status of samba server to check it run <strong> smbstatus</strong> command <br /> <img alt="smbstatus" border="0" class="padded s5_lazyload" height="284" src="http://computernetworkingnotes.com/images/rhce_certification/image/ass36_smbstatus.jpg" style="opacity: 1;" width="600" /><br /> in output you see that one <strong> samba shared directory</strong> is used on window system<br /><br /></div>

What is Samba? Configure samba server.

Tukiyooo 0 09:02

What is Samba? Samba is a software package that gives network administrators flexibility and freedom in terms of setup, configuration, and choice of systems and equipment. Because of all that it offers, Samba has grown in popularity, and continue… Read more »

Read more »

What is ACL and Basic of Access Control List

<div dir="ltr" style="text-align: left;" trbidi="on"><h1 class="firstHeading" id="firstHeading" lang="en"><span dir="auto">Access Control Lists</span></h1><br /><b>ACL stand for A</b>ccess <b>C</b>ontrol <b>L</b>ist (ACL) provides an additional, more flexible permission mechanism for file systems. It is designed to assist with <code>UNIX</code> file permissions. ACL allows you to give permissions for any user or group to any disc resource.<br /><br />ACL is a listing containing one or more that tells a computer operating system or other network device what rights users have to each item on a computer or network device.<img alt="Securing Access Control Lists" class="attachment-post-thumbnail wp-post-image" height="165" src="http://blog.pluralsight.com/wp-content/uploads/2012/05/securing-access-control-lists_featured-image.jpg" title="Securing Access Control Lists" width="640" /> <br /><span style="color: blue;"><b><span style="font-size: x-large;"><br /></span></b></span><span style="color: blue;"><b><span style="font-size: x-large;">Syntax </span></b></span><br /><br />Displays or modifies access control lists (ACLs) of files<br /> CACLS filename [/T] [/E] [/C] [/G user:perm] [/R user [...]] [/P user:perm [...]] [/D user [...]]<br /> <table class="mtable"> <tbody><tr class="tcw"> <td>filename</td> <td>Displays ACLs.</td> </tr><tr class="tcw"> <td>/T</td> <td>Changes ACLs of specified files in the current directory and all subdirectories.</td> </tr><tr class="tcw"> <td>/E</td> <td>Edit ACL instead of replacing it.</td> </tr><tr class="tcw"> <td>/C</td> <td>Continue on access denied errors.</td> </tr><tr class="tcw"> <td>/G user:perm</td> <td>Grant specified user access rights. <table cellpadding="0" cellspacing="0"> <tbody><tr> <td>Perm can be: R</td> <td>Read</td> </tr><tr> <td align="right" width="50%">W</td> <td>Write</td> </tr><tr> <td align="right" width="50%">C</td> <td>Change (write)</td> </tr><tr> <td align="right" width="50%">F</td> <td>Full control</td> </tr></tbody></table></td> </tr><tr class="tcw"> <td>/R user</td> <td>Revoke specified user's access rights (only valid with /E).</td> </tr><tr class="tcw"> <td>/P user:perm</td> <td>Replace specified user's access rights. <table cellpadding="0" cellspacing="0"> <tbody><tr> <td>Perm can be: N</td> <td>None</td> </tr><tr> <td> <div align="right">R</div></td> <td>Read</td> </tr><tr> <td align="right" width="50%">W</td> <td>Write</td> </tr><tr> <td align="right" width="50%">C</td> <td>Change (write)</td> </tr><tr> <td align="right" width="50%">F</td> <td>Full control</td> </tr></tbody></table></td> </tr><tr class="tcw"> <td>/D user</td> <td>Deny specified user access.</td> </tr></tbody></table>Wildcards can be used to specify more that one file in a command. You can specify more than one user in a command.<br /> <div class="nb"><a href="http://www.blogger.com/null" name="04"></a>Examples</div><div class="tcy">cacls myfile.txt</div>Displays the ACLs for the myfile.txt file. Below is an example of what this may look like.<br /> <table cellpadding="0" cellspacing="0"> <tbody><tr> <td>C:\WINNT\MYFILE.TXT</td> <td>BUILTIN\Users:R<br />BUILTIN\Power Users:C<br />BUILTIN\Administrators:F<br />NT AUTHORITY\SYSTEM:F</td> </tr></tbody></table><div class="tcy">cacls myfile.txt /e /g mrhope:f</div><br /><br /><br /><br /><br /><br /><br /><br /><br /></div>

What is ACL and Basic of Access Control List

Tukiyooo 0 02:42

Access Control ListsACL stand for Access Control List (ACL) provides an additional, more flexible permission mechanism for file systems. It is designed to assist with UNIX file permissions. ACL allows you to give permissions for any user or group to … Read more »

Read more »

How to Installing the Red Hat Virtualization environment

<div dir="ltr" style="text-align: left;" trbidi="on"><span style="color: blue;"><b><span style="font-size: large;">Scenario:</span></b></span> In this sequence, you will install and configure an existing Red Hat<br />Enterprise Linux system with the software and tools needed to use Red Hat<br />Virtualization<br /><br /><span style="color: blue;"><b><span style="font-size: large;">Instructions:</span></b></span><br />1. Configure yum to get software packages from server1.example.com. Download a repository<br />configuration file from ftp://server1.example.com/pub/gls/server1.repo<br />and save it as /etc/yum.repos.d/server1.repo on your workstation.<br />2. Verify that your CPU supports the PAE feature required by Red Hat Virtualization.<br />3. Edit /etc/sysconfig/kernel to set kernel-xen to be your preferred kernel<br />package.<br />4. Install the packages required for Domain-0 in the virtualization environment: kernelxen,<br />xen, and virt-manager.<br />5. Verify that the kernel-xen kernel will be chosen by default at boot, and that the xend<br />service will start at boot.<br />6. Reboot the hardware to enable virtualization. Verify that the correct kernel is running.<br /><br /></div>

How to Installing the Red Hat Virtualization environment

Tukiyooo 0 22:33

Scenario: In this sequence, you will install and configure an existing Red HatEnterprise Linux system with the software and tools needed to use Red HatVirtualizationInstructions:1. Configure yum to get software packages from server1.example.com. Down… Read more »

Read more »

Linux FTP Server Configuration Setup & What is FTP Server?

<div dir="ltr" style="text-align: left;" trbidi="on"><span style="color: blue;"><span style="font-size: large;">What is FTP Server?</span></span><br /><br />FTP ( File Transfer Protocol ) it is Standard network protocol & used for file transferring protocol.<br />Or other miens  <br />File Transfer Protocol is a standard network protocol used to transfer files from one host to another host over a TCP-based network, such as the Internet. FTP is built on a client-server architecture and uses separate control and data connections between the client and the server.<br /><br /><span style="color: blue;"><span style="font-size: large;">Interdiction of FTP Server:</span></span><br />The File Transfer Protocol (FTP) is used as one of the most common means of copying files between servers over the Internet. Most web based download sites use the built in FTP capabilities of web browsers and therefore most server oriented operating systems usually include an FTP server application as part of the software suite. Linux is no exception. <br /><br />Step by Step :<br /><br /><br /><h2>FTP Server</h2>This section covers the File Transport Protocol (FTP) information needed for both the RHCSA and RHCE exams.<br /> <h3>FTP Server : Installation</h3>Issue the following command to install the FTP server.<br /> <blockquote><pre># yum install vsftpd</pre></blockquote>Turn on the FTP server and make sure it starts automatically on reboot.<br /> <blockquote><pre># service vsftpd start<br /># chkconfig vsftpd on</pre></blockquote>The FTP server is now installed and running. The FTP configuration files are located under the "/etc/vsftpd" directory, specifically the "/etc/vsftpd/vsftpd.conf" file. The default directory for anonymous connections is "/var/ftp". Changes to the "/etc/vsftpd/vsftpd.conf" file have to be followed by a reload or a restart of the httpd service.<br /> <blockquote><pre># service vsftpd reload<br /># # OR<br /># service vsftpd restart</pre></blockquote><h3>FTP Server : Firewall</h3>You need to punch a hole in the firewall for port 21 to make sure the FTP server can be accessed from the network. There are several ways to do this:<br /> <ul><li>The "Firewall Configuration" dialog from the menu (System > Administration > Firewall) or initiated from the command line by running the <code>system-config-firewall</code> command. On the "Trusted Services" section, scroll down the list and check the "FTP" option, then click the "Apply" button.</li><li>The text-based "Firewall Configuration" utility (<code>system-config-firewall-tui</code>). This is the text-based version of the above dialog.</li><li>Using the <code>iptables</code> service directly, as described <a href="http://www.oracle-base.com/articles/linux/linux-firewall.php">here</a>. In this case we could need the following entry.<br /> <blockquote><pre>iptables -A INPUT -p tcp --dport 21 -j ACCEPT</pre></blockquote></li></ul><h3>FTP Server : SELinux</h3>If you are using SELinux, you will need to consider the following points.<br /> The SELinux booleans associated with the <code>vsftpd</code> service are displayed using the <code>getsebool</code> command.<br /> <blockquote><pre># getsebool -a | grep ftpd<br />allow_ftpd_anon_write --> off<br />allow_ftpd_full_access --> off<br />allow_ftpd_use_cifs --> off<br />allow_ftpd_use_nfs --> off<br />ftpd_connect_db --> off<br />ftpd_use_passive_mode --> off<br />#</pre></blockquote>The <code>setsebool</code> command is used to set a specific boolean value.<br /> <blockquote><pre># setsebool ftpd_use_passive_mode on<br /># setsebool ftpd_use_passive_mode off</pre></blockquote>The <code>public_content_t</code> context should be assigned to all public content.<br /> <blockquote><pre># semanage fcontext -a -t public_content_t "/var/ftp(/.*)?"<br /># restorecon -F -R -v /var/ftp</pre></blockquote>You can check the current context setting on files and directories using the "ls -alZ" command.<br /> More information on SELinux can be found <a href="http://www.oracle-base.com/articles/linux/security-enhanced-linux.php">here</a>.<br /> <h3>FTP Server : Security</h3>By default the FTP installation allows anonymous access, which is potentially dangerous. This is fine for the RHCSA exam, but on real servers you would probably want to disable anonymous access. To do this, edit the "/etc/vsftpd/vsftpd.conf" file, setting the "anonymous_enable" entry as follows.<br /> <blockquote><pre>anonymous_enable=NO<br />local_enable=YES</pre></blockquote>The "local_enable" options indicates that local user accounts can be used for authentication.<br /> Restart or reload the FTP service for the changes to take effect.<br /> <blockquote><pre># service vsftpd reload</pre></blockquote>The RHCE exam has a requirement for configuring an anonymous-only download FTP server. This can be done by setting the following values in the "/etc/vsftpd/vsftpd.conf" file, then restarting the service.<br /> <blockquote><pre>anonymous_enable=YES<br />anon_upload_enable=NO<br />local_enable=NO</pre></blockquote>Try and ping ftp server connect for Example :<br /><br /><br />Go on client system and check banner it will appear before user login<br /><br /> <img alt="" border="0" class="padded s5_lazyload" height="85" src="http://computernetworkingnotes.com/images/rhce_certification/image/ass30_banner_xp.jpg" style="opacity: 1;" width="381" /> <br /><br /><br /><span style="font-size: large;"><u> EndCall:</u></span><br />FTP is a very useful software application that can have enormous benefit to a Web site or to collaborative computing in which files need to be shared between business partners. Although insecure, it is universally accessible, because FTP clients are a part of all operating systems and Web browsers. If data encryption security is of great importance to you, then you should probably consider SCP as a possible alternative <br /><br />For more information :<br /><br /><ul><li><a href="http://www.oracle-base.com/articles/linux/linux-http-server-configuration.php">Linux HTTP Server Configuration (RHCE)</a></li><li><a href="https://access.redhat.com/knowledge/docs/en-US/Red_Hat_Enterprise_Linux/6/html/Managing_Confined_Services/chap-Managing_Confined_Services-File_Transfer_Protocol.html">RHEL6 : Managing Confined Services : File Transfer Protocol (FTP)</a></li><li><a href="https://security.appspot.com/vsftpd/vsftpd_conf.html">vsftpd.conf</a></li><li><a href="http://docs.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/index.html">RHEL6 Documentation</a></li><li><a href="http://linux.die.net/man/">Linux man pages</a></li><li><a href="http://www.oracle-base.com/articles/linux/articles-linux.php#rhcsa_and_rhce">RHCSA and RHCE</a></li><li><a href="http://www.oracle-base.com/articles/linux/apache-tomcat-installation-on-linux.php">Apache Tomcat Installation on Linux</a></li><li><a href="http://www.oracle-base.com/articles/misc/apache-reverse-proxy-configuration.php">Apache : Reverse Proxy Configuration</a></li></ul><br /><br /><br /></div>

Linux FTP Server Configuration Setup & What is FTP Server?

Tukiyooo 0 21:21

What is FTP Server?FTP ( File Transfer Protocol ) it is Standard network protocol & used for file transferring protocol.Or other miens  File Transfer Protocol is a standard network protocol used to transfer files from one host to another host over a… Read more »

Read more »

NAT Configuration in Linux

<div dir="ltr" style="text-align: left;" trbidi="on"><a href="http://www.newstips24.blgspot.com/"></a><br /><div dir="ltr" style="text-align: left;" trbidi="on"><span style="font-size: large;"><b>NAT ( Network Address Translation) Configuration:</b></span><br /><br /><b><u>What is NAT ?</u> </b><br /><b>Network Address Translation is the process where a network device, usually a firewall, assigns a public address to a computer (or group of computers) inside a private network. The main use of NAT is to limit the number of public IP addresses an organization or company must use, for both economy and security purposes.</b><br /><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody><tr><td style="text-align: center;"><img alt="Computer Networking Image Gallery" height="116" src="http://static.ddmcdn.com/gif/nat-router.jpg" style="height: 146px; margin-left: auto; margin-right: auto; width: 400px;" title="Computer Networking Image Gallery" width="320" /></td></tr><tr><td class="tr-caption" style="text-align: center;">Add caption</td><td class="tr-caption" style="text-align: center;"></td><td class="tr-caption" style="text-align: center;"></td><td class="tr-caption" style="text-align: center;"></td><td class="tr-caption" style="text-align: center;"></td></tr></tbody></table><b> NAT Configure:</b><br /><b>You apply system that solve you nat problems----------</b><br /><h3>Configure Step by Step </h3><b>Step #1.</b> Add Two Network cards to the Linux box<br /><br /><b>Step #2.</b> Verify the Network cards, Wether they installed properly or not<br /><div class="command">ls /etc/sysconfig/network-scripts/ifcfg-eth* | wc -l</div>    ( The output should be "Two")<br /><br /><b>Step #3.</b> Configure eth0 for Internet with a Public ( IP Address External network or Internet)<br /><div class="command">cat /etc/sysconfig/network-scripts/ifcfg-eth0</div><div class="command"><br /></div><span class="system">DEVICE=eth0<br />BOOTPROTO=none<br />BROADCAST=xx.xx.xx.255    # Optional Entry<br />HWADDR=00:50:BA:88:72:D4    # Optional Entry<br />IPADDR=xx.xx.xx.xx<br />NETMASK=255.255.255.0    # Provided by the ISP<br />NETWORK=xx.xx.xx.0       # Optional<br />ONBOOT=yes<br />TYPE=Ethernet<br />USERCTL=no<br />IPV6INIT=no<br />PEERDNS=yes<br />GATEWAY=xx.xx.xx.1    # Provided by the ISP</span><br /><br /><b>Step #4.</b> Configure eth1 for LAN with a Private IP (Internal private network)<br /><div class="command">cat /etc/sysconfig/network-scripts/ifcfg-eth1</div><div class="command"><br /></div><span class="system">BOOTPROTO=none<br />PEERDNS=yes<br />HWADDR=00:50:8B:CF:9C:05    # Optional <br />TYPE=Ethernet<br />IPV6INIT=no<br />DEVICE=eth1<br />NETMASK=255.255.0.0        # Specify based on your requirement<br />BROADCAST=""<br />IPADDR=192.168.2.1        # Gateway of the LAN<br />NETWORK=192.168.0.0        # Optional<br />USERCTL=no<br />ONBOOT=yes</span><br /><br /><b>Step #5.</b> Host Configuration   <br /><div class="command">cat /etc/hosts</div><div class="command">   127.0.0.1       nat localhost.localdomain   localhost</div><span class="system"></span><br /><b>Step #6.</b> Gateway Configuration  (really set Getway)  <br /><div class="command">cat /etc/sysconfig/network</div><span class="system">   </span><br /><span class="system"> NETWORKING=yes<br />    HOSTNAME=nat<br />    GATEWAY=xx.xx.xx.1    # Internet Gateway, provided by the ISP</span><br /><br /><b>Step #7. </b>DNS Configuration<br /><div class="command">cat /etc/resolv.conf</div><span class="system">    nameserver 102.108.184.25      # Primary DNS Server provided by the ISP<br />    nameserver 102.56.250.5        # Secondary DNS Server provided by the ISP</span><br /><br /><b>Step #8.</b> NAT configuration with IP Tables<br />    # Delete and flush. Default table is "filter". Others like "nat" must be explicitly stated.<br /><div class="command">iptables --flush            # Flush all the rules in filter and nat tables</div><div class="command">iptables --table nat --flush</div><div class="command">iptables --delete-chain</div># Delete all chains that are not in default filter and nat table<br /><div class="command">iptables --table nat --delete-chain</div># Set up IP FORWARDing and Masquerading<br /><div class="command">iptables --table nat --append POSTROUTING --out-interface eth0 -j MASQUERADE</div><div class="command">iptables --append FORWARD --in-interface eth1 -j ACCEPT</div># Enables packet forwarding by kernel<br /><div class="command">echo 1 > /proc/sys/net/ipv4/ip_forward</div> #Apply the configuration<br /><div class="command">service iptables restart</div><br /><b>Step #9. </b>Testing<br /> # Ping the Gateway of the network from client system<br /><div class="command">ping 192.168.2.1</div>Try it on your client systems<br /><div class="command">ping google.com</div><h3> Configuring PCs on the network (Clients)</h3>•    All PC's on the private office network should set their "gateway" to be the local private network IP address of the Linux gateway computer. <br />•    The DNS should be set to that of the ISP on the internet. <br />Windows '95, 2000, XP,  Configuration:<br /><br />•    Select "Start" + Settings" + "Control Panel" <br />•    Select the "Network" icon <br />•    Select the tab "Configuration" and double click the component "TCP/IP" for the ethernet card. (NOT the TCP/IP -> Dial-Up Adapter) <br />•    Select the tabs: <br />o    "Gateway": Use the internal network IP address of the Linux box. (192.168.2.1) <br />o    "DNS Configuration": Use the IP addresses of the ISP Domain Name Servers. (Actual internet IP address) <br />o    "IP Address": The IP address (192.168.XXX.XXX - static) and netmask (typically 255.255.0.0 for a small local office network) of the PC can also be set here. <br /><h3><u>Common Problems in Linux:</u></h3><h3>The most common problem or question I receive about this is related to DNS. The instructions above setup the network to route the packets for you, but if your DNS isn't setup correctly (or at all) you won't be able to reference sites by their domain or hostnames. If at first you think this isn't working for you, plese try to ping an external IP address. If you can do this, then your problem is with DNS and not iptables. </h3><br /><b>Related Books And Tips :</b><br /><ul><li><a href="http://www.amazon.com/gp/product/0596005695/ref=as_li_ss_tl?ie=UTF8&tag=linux-nat-20&linkCode=as2&camp=217145&creative=399349&creativeASIN=0596005695">Linux iptables Pocket Reference</a><img alt="" border="0" height="1" src="http://www.assoc-amazon.com/e/ir?t=&l=as2&o=1&a=0596005695&camp=217145&creative=399349" style="border: none !important; margin: 0px !important;" width="1" /></li><li><a href="http://www.amazon.com/gp/product/0596102488/ref=as_li_ss_tl?ie=UTF8&tag=linux-nat-20&linkCode=as2&camp=217145&creative=399349&creativeASIN=0596102488">Linux Networking Cookbook</a><img alt="" border="0" height="1" src="http://www.assoc-amazon.com/e/ir?t=&l=as2&o=1&a=0596102488&camp=217145&creative=399349" style="border: none !important; margin: 0px !important;" width="1" /></li><li><a href="http://www.amazon.com/gp/product/0596005482/ref=as_li_ss_tl?ie=UTF8&tag=linux-nat-20&linkCode=as2&camp=217145&creative=399349&creativeASIN=0596005482">Linux Network Administrator's Guide</a></li><li><a href="http://whatismyipaddress.com/routers">What is a router?</a></li><li><a href="http://whatismyipaddress.com/private-ip">What is a private IP address?</a></li><li><a href="http://whatismyipaddress.com/firewall">What is firewall?</a></li><li><a href="http://whatismyipaddress.com/dhcp">What is DHCP?</a></li><li><span style="color: blue;"><img alt="" border="0" height="1" src="http://www.assoc-amazon.com/e/ir?t=&l=as2&o=1&a=0596005482&camp=217145&creative=399349" style="border: none !important; margin: 0px !important;" width="1" /><a href="http://www.ipv4-ipv6.blogspot.com/" target="_blank">www.ipv4-ipv6.blogspot.com</a></span></li></ul></div></div>

NAT Configuration in Linux

Tukiyooo 0 01:59

NAT ( Network Address Translation) Configuration:What is NAT ? Network Address Translation is the process where a network device, usually a firewall, assigns a public address to a computer (or group of computers) inside a private network. The main … Read more »

Read more »

Smbclient or samba Client Configure

<div dir="ltr" style="text-align: left;" trbidi="on"><a href="http://www.ipv4-ipv6.blogspot.com/"></a><b><span style="font-size: x-large;">SMB or Samba Discription:</span></b><br />An SMB client program for UNIX machines is included with the Samba distribution. It provides an ftp-like interface on the command line. You can use this utility to transfer files between a Windows 'server' and a Linux client.<br /><br />This Command is used for see smbclient file or directory share :<br /><br />[root@myhost~]#smbclient -L Server1<br /><br />For access smb share  command :<br />[root@myhost~]#smbclient -U student // Server1/homes<br /><br />Now ssh service is must be do you running  or  you will Check command for SSH Service.<br />[root@myhost~]#service sshd status<br />[root@myhost~]#chkconfig --list | grep telnet<br /><br />And Client machine command for used:<br /><br />[root@myhost~]#telnet hostname<br />[root@myhost~]#telnet myshost1.example.com<br />[root@myhost~]#ssh user@hostname<br />[root@myhost~]#ssh user@hostname command<br />[root@myhost~]#<br /><br /><br />For Example:<br />[root@myhost~]#ssh asraful@myhost1.example.com <br /><br />[root@myhost~]#ssh asraful@server1 'df -h'<br /><br />Now You will Copy, Cut , Past Command is 'scp -r '  'scp -p'  'scp -c'<br />For More help: <span style="font-size: large;"><a href="http://www.linux.org/" target="_blank">www.linux.org</a></span><br /><br /><br /><br />Briefing for SMB Server:  <br />An SMB client program for UNIX machines is included with the Samba distribution. It provides an ftp-like interface on the command line. You can use this utility to transfer files between a Windows 'server' and a Linux clien</div>

Smbclient or samba Client Configure

Tukiyooo 0 22:00

SMB or Samba Discription:An SMB client program for UNIX machines is included with the Samba distribution. It provides an ftp-like interface on the command line. You can use this utility to transfer files between a Windows 'server' and a Linux cl… Read more »

Read more »

NFS Server Red Hat Enterprise in system Administration

<div dir="ltr" style="text-align: left;" trbidi="on"><span style="color: blue;"><span style="font-size: x-large;"><b>What is NFS Server:</b></span></span><br /><strong>Network File System,</strong> is a server-client protocol for sharing files system between computers on a common network. NFS enables you to mount a file system on a remote computer as if it were local to your own system. You can then directly access any of the files on that SSH / Telnet / remote file system. The server and client do not have to use the same operating system. The client system just needs to be running an <strong> NFS client</strong> compatible with the <strong> NFS server</strong>.<br /><br /><strong>For example:</strong><br /><strong> NFS server</strong> could be a Linux system and Unix could be a client. But it can’t be a window system because window is not NFS compatible. The NFS server exports one or more directories to the client systems, and the client systems mount one or more of the shared directories to local directories called mount points. After the share is mounted, all I/O operations are written back to the server, and all clients notice the change as if it occurred on the local filesystem.<br />A manual refresh is not needed because the client accesses the remote filesystem as if it were local.because access is granted by IP address, a username and password are not required. However, there are security risks to consider because the <strong> NFS server</strong> knows nothing about the users on the client system.<br /><br /><b>Therefore</b> NFS System is the best System in the world . it is very easy , or very best system than  windows system  .<br /><br /><br /><br /><a href="http://computernetworkingnotes.com/linux-network-administrations/network-configurations.html">Network configuration in Linux </a><br /><ul class="ul_arrow"><li>A linux server with ip address 192.168.0.254 and hostname Server</li><li>A linux client with ip address 192.168.0.1 and hostname Client1</li><li>Updated /etc/hosts file on both linux system</li><li>Running portmap and xinetd services</li><li>Firewall should be off on server</li></ul>We suggest you to review that article before start configuration of nfs server. Once you have completed the necessary steps follow this guide.Three rpm are required to configure nfs server. <strong> nfs, portmap, xinetd </strong> check them if not found then install<br /> <img alt="rpm" border="0" class="padded s5_lazyload" height="135" src="http://computernetworkingnotes.com/images/rhce_certification/image/ass33_ser_rpm.jpg" style="opacity: 1;" width="310" /><br />Now check <strong> nfs, portmap, xinetd</strong> service in system service it should be on<br /><div class="code"><pre>#setup<br />Select <strong> System service</strong><br />from list<br />[*]portmap [*]xinetd [*]nfs<br /></pre></div>Now restart <strong> xinetd</strong> and <strong> portmap</strong> service<br /> <img alt="service restart" border="0" class="padded s5_lazyload" height="119" src="http://computernetworkingnotes.com/images/rhce_certification/image/ass24_service_restart.jpg" style="opacity: 1;" width="607" /><br /> To keep on these services after reboot on then via <strong> chkconfig</strong> command<br /> <img alt="chkconfig" border="0" class="padded s5_lazyload" height="55" src="http://computernetworkingnotes.com/images/rhce_certification/image/ass24_chkconfig.jpg" style="opacity: 1;" width="337" /><br /> After <strong> reboot</strong> verify their status. It must be in<strong> running</strong> condition<br /> <img alt="service status" border="0" class="padded s5_lazyload" height="84" src="http://computernetworkingnotes.com/images/rhce_certification/image/ass24_service_status.jpg" style="opacity: 1;" width="354" /><br />now create a <strong> /data</strong> directory and grant full permission to it<br /> <img alt="mkdir" border="0" class="padded s5_lazyload" height="53" src="http://computernetworkingnotes.com/images/rhce_certification/image/ass33_ser_mkdir.jpg" style="opacity: 1;" width="299" /><br />now open <strong> /etc/exports</strong> file <br /> <img alt="vi exports" border="0" class="padded s5_lazyload" height="25" src="http://computernetworkingnotes.com/images/rhce_certification/image/ass33_ser_vi_file.jpg" style="opacity: 1;" width="318" /><br /> share<strong> data</strong> folder for the network of <strong> 192.168.0.254/24 </strong>with read and write access <br /> <img alt="editing in exports" border="0" class="padded s5_lazyload" height="22" src="http://computernetworkingnotes.com/images/rhce_certification/image/ass33_ser_file_edit.jpg" style="opacity: 1;" width="369" /><br /> save file with <strong> :wq</strong> and exit<br />now restart the <strong> nfs service</strong> and also on it with<strong> chkconfig</strong> <br /> <img alt="service nfs restart" border="0" class="padded s5_lazyload" height="263" src="http://computernetworkingnotes.com/images/rhce_certification/image/ass33_ser_service_restart.jpg" style="opacity: 1;" width="622" /><br /> also restart <strong> nfs daemons</strong> with <strong> expotfs</strong> <br /> <img alt="exportfs" border="0" class="padded s5_lazyload" height="41" src="http://computernetworkingnotes.com/images/rhce_certification/image/ass33_ser_export_r.jpg" style="opacity: 1;" width="258" /><br />verify with <strong> showmount</strong> command that you have successfully shared <strong> data folder</strong><br /> <br /><br /><br /><br /><br /><img alt="showmount" border="0" class="padded s5_lazyload" height="67" src="http://computernetworkingnotes.com/images/rhce_certification/image/ass33_ser_showmount.jpg" style="opacity: 1;" width="269" /><br /><h3>Or apply this system:</h3>Every file system being exported to remote users via NFS, as well as the access level for those file systems, are listed in the <tt class="FILENAME">/etc/exports</tt> file. When the <tt class="COMMAND">nfs</tt> service starts, the <tt class="COMMAND">/usr/sbin/exportfs</tt> command launches and reads this file, passes control to <tt class="COMMAND">rpc.mountd</tt> (if NFSv2 or NFSv3) for the actual mounting process, then to <tt class="COMMAND">rpc.nfsd</tt> where the file systems are then available to remote users. <br /> When issued manually, the <tt class="COMMAND">/usr/sbin/exportfs</tt> command allows the root user to selectively export or unexport directories without restarting the NFS service. When given the proper options, the <tt class="COMMAND">/usr/sbin/exportfs</tt> command writes the exported file systems to <tt class="FILENAME">/var/lib/nfs/xtab</tt>. Since <tt class="COMMAND">rpc.mountd</tt> refers to the <tt class="FILENAME">xtab</tt> file when deciding access privileges to a file system, changes to the list of exported file systems take effect immediately. <br /> The following is a list of commonly used options available for <tt class="COMMAND">/usr/sbin/exportfs</tt>: <br /><h3> </h3><h3>configure client system</h3>ping form <strong> nfs server</strong> and check the<strong> share folder</strong> <br /> <img alt="showmount" border="0" class="padded s5_lazyload" height="69" src="http://computernetworkingnotes.com/images/rhce_certification/image/ass33_cl_showmount.jpg" style="opacity: 1;" width="402" /><br />now <strong> mount</strong> this share folder on<strong> mnt </strong>mount point. To test this share folder change directory to<strong> mnt</strong> and create a <strong> test file</strong> <br /> <img alt="mount server directory" border="0" class="padded s5_lazyload" height="83" src="http://computernetworkingnotes.com/images/rhce_certification/image/ass33_cl_mount.jpg" style="opacity: 1;" width="500" /><br />After use you should always <strong> unmount</strong> from <strong> mnt</strong> mount point<br /> <img alt="unmount" border="0" class="padded s5_lazyload" height="56" src="http://computernetworkingnotes.com/images/rhce_certification/image/ass33_cl_unmount.jpg" style="opacity: 1;" width="269" /><br />In this way you can use <strong> shared folder</strong>. But this share folder will be available till system is <strong> up</strong>. It will not be available after <strong> reboot</strong>. To keep it available after reboot make its entry in <strong> fstab</strong><br />create a<strong> mount point</strong>, by making a directory <br /> <img alt="mkdir" border="0" class="padded s5_lazyload" height="22" src="http://computernetworkingnotes.com/images/rhce_certification/image/ass33_cl_mkdir_temp.jpg" style="opacity: 1;" width="274" /><br />now open <strong> /etc/fstab</strong> file <br /> <img alt="vi fstab" border="0" class="padded s5_lazyload" height="19" src="http://computernetworkingnotes.com/images/rhce_certification/image/ass33_vi_fstab.jpg" style="opacity: 1;" width="309" /><br /> make entry for <strong> nfs</strong> shared directory and define<strong> /temp to mount point</strong><br /><img alt="file fstab" border="0" class="padded s5_lazyload" height="166" src="http://computernetworkingnotes.com/images/rhce_certification/image/ass33_cl_file_fstab.jpg" style="opacity: 1;" width="682" /><br /><div class="custom"><div class="link_text_laybord"> <ins style="background-color: transparent; border: none; display: inline-table; height: 15px; margin: 0; padding: 0; position: relative; visibility: visible; width: 728px;"><ins id="aswift_3_anchor" style="background-color: transparent; border: none; display: block; height: 15px; margin: 0; padding: 0; position: relative; visibility: visible; width: 728px;"></ins></ins> </div></div>save the with<strong> :wq</strong> and exit reboot the system with <strong> reboot -f</strong> command<br /><div class="code"><pre><strong> #reboot -f </strong></pre></div>after reboot check <strong> /temp</strong> directory it should show all the <strong> shared data</strong> <br /> <img alt="cd temp" border="0" class="padded s5_lazyload" height="71" src="http://computernetworkingnotes.com/images/rhce_certification/image/ass33_cl_cd_temp.jpg" style="opacity: 1;" width="248" /><br /><br />For more information:<br /><span style="font-size: large;"><a href="http://www.linux.org/"><span style="color: blue;"><cite><b>www</b>.<b>linux</b>.<b>org</b>/</cite></span></a></span><br /><br /><br /><span style="font-size: large;"><span style="color: blue;"><cite> </cite></span>‎</span></div>

NFS Server Red Hat Enterprise in system Administration

Tukiyooo 0 09:09

What is NFS Server:Network File System, is a server-client protocol for sharing files system between computers on a common network. NFS enables you to mount a file system on a remote computer as if it were local to your own system. You can then di… Read more »

Read more »