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DNS, LDAP and JMS on Linux – More Cost Effective and Reliable!

April 30th, 2012 No comments

DNS, LDAP and JMS are Linux based web servers, which are more cost effective and reliable than other expensive operating systems. Main advantages of these servers are that they are running smoothly on the less expensive hardware. However, the other operating systems require specific hardware and setting.   These are also having advanced security systems that are more essential for the users to protect their important data from outside interference.   These servers are completely customized both in the built and design for the users to keep it at their home.  Due to these reasons, the users can access these Linux based servers easily than any other server designs. You may set up the DNS server for many different reasons:

Internet Domain Support: In case, you have the domain name & you are operating the Web, FTP, e-mail, and other servers, you can then use the DNS server for responding to the resolution queries thus others will find access your servers. It is the serious undertaking & you would need to set up the minimum of 2. On the page we can refer these kinds of the DNS servers as the authoritative servers for the reasons you can see later. But, there are some alternatives of having your DNS server in case, you have your domain name. You may also have somebody host the DNS records for you. Even though somebody is taking good care of the domain’s DNS records you can set up one of following kinds of the DNS servers.

Local Name Resolution: Same to above case, this kind of the DNS server will resolve hostnames of the systems on LAN. Generally, in this case there is a DNS server & it does both the jobs. First being it gets the queries from the workstations and second being it serves as authoritative source for responses (this is clear when we progress). To have this kind of the DNS server will eliminate need of having (and update) the HOSTS file on every system on the LAN. On this webpage we can refer as LAN DNS servers.

Categories: General, linux Tags: ,

DNS, LDAP and JMS on Linux – Offering Speed Processing Of the Server!

April 29th, 2012 No comments

DNS, LDAP and JMS are the Linux based server that is making the networking process easier. The DNS based Linux requires a local name resolution. These types of servers should determine the hostname of the system on the users LAN. Basically, the DNS server is making entire web based programs more faster that the users can easily access any application. All the web masters are known the advantage and processing speed of the server. So, the use of the DNS, LDAP and JMS servers are replacing other server in the web processing work. These servers are not required the hosts files like other server manufactures. For this reason, real Internet server requires the static (and unchanging) IP address.

Do not take from this you require 3 different kinds of the DNS servers. In case, you were setting up the couple authoritative then DNS servers can as well give functionality of the LAN as well as simple DNS servers. The LAN DNS server will simultaneously give functionality of the simple DNS server and it is the progressive type of the thing. Finding the single server from all of servers on Internet is just like trying to find the single file on the drive with many files. In both the cases it helps having a few hierarchy built in a directory to logically group the things.

DNS “namespace” is the hierarchical in same kind of the upside down tree structure that was seen with the file systems. As you have root of the partition and drive, DNS namespace has the root that is been signified by the period. Internet sources are generally specified by the domain name as well as server hostname. WWW part of the URL is the hostname of Web server (and it can be the alias to server with different host name). The DNS is generally the database with the records for hostnames. Directory for entire telephone system is not at all stored in a huge phone book.

Categories: General, linux Tags: ,

DNS, LDAP and JMS on Linux – Creating Possibility to Draw More Internet Traffic!

April 28th, 2012 No comments

Domain name for any server is playing a major role to boost the flow of Internet traffic.  However, the DNS server is an element of the global networks of the server that decode the host name into numerical Internet Protocol address. These are also more essential for the computers to connect with each other and make the communication process easier. It is also permitting the users to simply memorize the URLs and Email address in place of large string of numbers.  The main advantage of the DNS server on the Linux is to develop the needs of traffic on the user’s internal network without having to rely on other DNS server that located out of their network.

Thus, which DNS server has DNS records for the domain? Whenever you register the domain name with somebody like the Network Solutions, one things that they ask you are server names & addresses of 2 and 3 “name servers” (the DNS servers). And these are servers where DNS records for the domain are been stored (as well queried by DNS servers of the browsing to site). Thus, where you get “name servers” information for the domain? Generally, when you host the Web site using the Web hosting service also they not just give the Web server for domain’s site files however they can as well give the DNS server for storing the domain’s DNS records. In some other words, you would like to know who the Web hosting provider will be prior to you register the domain name (thus you may enter provider’s DNS server information in name servers segment of domain name application).

Linux LDAP authentication

Whenever you want to administer the network of machines, you fast find out how much of duplication is involved with the normal administrative tasks. The routine operations such as canceling accounts, changing passwords, as well as modifying the groups become very time consuming in case, repeated on a lot of individual machines. Also, centralizing user & authentication information will solve the issues.

Categories: General, linux Tags: ,

DNS, LDAP and JMS on Linux – Easy For Users to Search JMS Related Topic!

April 27th, 2012 No comments

Users of java on the Linux are searching for the JMS related topic by JNDI Context. Once the connection of this topic is open and server is connecting with the powered down or not accessible to the network.  Also, the JNDI links will not timeout, so it is permitting the failover system required to use the secondary server. The similar code is also required for the Windows users to run the Linux server. It is also easy to access for the users that the users never required vast expertise to run it. So, the DNS, LDAP and JMS are working smoothly in the Linux.  As mentioned on Networking page, each system on Internet should have the unique IP address. (It will not include the systems, which are behind NAT firewall as they are not on Internet.)

The DNS acts as directory service for these systems, and allowing you specify every one by the hostname. The telephone book lets you look up the individual person by name as well as get the phone number, the unique identifier on telephone system’s network. The DNS also allows you look up the individual server by name as well as get the IP address, unique identifer on Internet. There are some other hostname to the IP directory services in the use, primarily for the LANs. The windows LANs will make use of WINS.

UNIX LANs will make use of NIS and because DNS is a directory service for Internet (and is used for the LANs) it is most widely used. The UNIX LANs can always make use of DNS in place of NIS, starting with the Windows 2000 Server, the Windows LANs can make use of DNS in place of, or WINS. On small LANs where you will see there are just some machines you can use the HOSTS files on every system in place of setting up the server running NIS, DNS, and WINS.

Categories: General, linux Tags: ,

Firewalls, Switches, Routers and VPN – Provide High Speed Network Communication!

April 26th, 2012 No comments

A switch is a hardware device that links the data where the Ethernet protocol works.  The switch is using the table to distinguish where to send all future frames that it receives. In technological term this tables is known as CAM table which is used for the bridge forwarding table. If a switch receives a frame with a destination then table floods that frame to all switch ports. It also put the Mac address in the table when it usually receives a frame. As we know switch is a high speed multiport bridge and most routers can also function as bridges.

The example of the SPI hardware firewall is the Cisco PIX firewall. It is the dedicated appliance as well as it looks like the Cisco router. The SPI firewall is stateful as it understands different states of TCP (the transmission control protocol). It knows what comes & what it goes & keeps the track of that all. Therefore, in case, the packet tried and come in however it was not requested, firewall knows that & drops that. Here is what we learned:

  • Routers work in Layer 3 & route IP packets between the networks.
  • Routers are been used to connect the LAN to WAN (like small network to Internet) however they will as well get used to connect the segments of large LAN, which is subnetted in the smaller segments.
  • Routers route the packets that are based on the information in IP routing table. You may see the table with show ip route command on the Cisco router.
  • Switches work in Layer 2 as well as switch Ethernet frames and switches connect the multiple devices on the local area network.
  • Switches keep the table of the Ethernet MAC addresses named the CAM Table or Bridge forwarding table. You may also see the table with show mac-address-table command at the Cisco switch.
  • Firewalls work in Layers 3 & 4 however some will work at the higher layers.

 

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Firewalls, Switches, Routers and VPN – Offering Quality Network Communication!

April 25th, 2012 No comments

These days, every types of business are hugely depending on the quality of its communication network. Information technology is much required for the business and your business will definitely struggle without the expertise of networking solution. Networking solution in relation to firewall, switches, router and VPN are the most respected communication solution in the business communication world. There is no further option than Cisco, when it comes to communications network. You will need expert assistance in the configuration of your system, once the right system has been determined. You can’t just guess what the right configuration for your company is. While it gets the response, it puts MAC address in a table so it will not need to flood the next time.

Router gets this, replaces source address, changes destination address to original address as well as sends this packet back to original sender. It is the complex topic, which we can spend the whole article covering thus this is just meant to give most basic understanding how it actually works. In order, to show routing table on a router, make use of show ip route command. So, here is the example of what the routing table looks very much like on the router:

Switch

The switch is the hardware device , which works at the Layer 2 of OSI model – the data link. Data link layer is actually where Ethernet protocol works. The switch switches the Ethernet frames just by keeping the table of what the MAC addresses are seen on what of the switch port. Switch makes use of the table to determine where you can send all the future frames, which it gets. In the Cisco terminology, table is named CAM table (the content addressable memory). Generally, proper term for the table is bridge forwarding table. In case, the switch gets the frame with destination MAC address it will not have in he table, it also floods frame to all the switch ports.

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Firewalls, Switches, Routers and VPN – Improving Capabilities of Every Device!

April 23rd, 2012 No comments

Business devices have become more and more unite over time just like home devices. Network administrators in a business network are always comfortable with separate devices because they like to be cut off problems to a certain device to know the performance capabilities of every device. If you are using integrated router, firewall, switches all into one device then understanding the performance capabilities of every device can be get complicated. You should remember that these integrated devices won’t work well for medium or large size business because they don’t offer all the features required. The firewall, switches, routers and VPN has all the features that you require.

In an event that destination is not at all listed in routing table, router can either send a packet to the default router (in case, it has one) and drop packet. The routers are generally used to connect the local area network to the wide area network (LAN to WAN) but will as well get used to segment the large local area (LAN’s). The routers stop broadcasts and one more method to save this is routers form the broadcast domain. Thus, in case, the network is to be deluged by the IP broadcasts, you have to subnet the network in 2 and more smaller networks.

These networks will get connected by the router and this router will not allow the broadcast traffic to flow it between the subnets. The routers make use of routing dynamic protocols such as RIP, OSPF, and BGP to learn the routes from some other routers. The router will as well make use of static routes, which are entered by administrator. The routers replace Ethernet MAC address of source device with the own MAC address while they send the packet out the interface. While response to this packet comes back, new source of a packet is now sending response to destination of a router.

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Firewalls, Switches, Routers and Vpn – Much Required for Network Configuration!

April 22nd, 2012 No comments

If you are working with your home networking gear, then you must use such integrated device that does it all. You may have 1 box that is a router, firewall, and switch on a home network all in one. Really it’s quite interesting that all the function can fit into one box. Now, there is a quicker and simpler way to get more performance and value out of your network. A router is a hardware device works at layer 3 of the network layer. These days, most of the routers are verifying the source and destination IP address of each packet and route that packet on its way. In case, you are been used to working with the home networking gear that you are used to integrated device “does it all”. On the home network, you might have a box, which is the cable or DSL modem, firewall, router, wireless access point and switch, in one. Also, it is very amazing all functions they will fit in a box today.

In case, you study the Cisco networking & learning about how the businesses make use of the devices, you are thinking wondering why there is a lot of importance on differences between the switch, firewall, router, as well as other devices. In case, home user will have all the devices combined in one, why does not business user do as well? The article can try to answer this question as well as cover differences between the devices.

Integrated devices

Like home devices, and business devices have now become more consolidated with time however not to an extent that home devices have. The network administrators in the business network are comfortable to have the separate devices and like an idea. It is because the network administrators love to isolate the problems down to the certain device as well as they love to know performance abilities of each device. In case, you make use of the integrated router, firewall and switch, all in a device, troubleshooting, understanding and managing, performance capabilities of this device gets very complicated.

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Performance Tuning Apache Web Server on Linux – Available With Easy Features!

April 21st, 2012 No comments

If you are looking for easy access and high performance web server, then the Linux based Apache web server is right for you.  It is also faster and reliable than the Windows NT and UNIX based server.  Only the users are required some easy cords to operate it.  You can also remind that all the files required httpd before search in the Apache web server.  However, it is never so critical to access like the Windows NT and UNIX due to easy features.   In case of new web master, it is always better to access the Apache web server of the Linux system as per instruction.

Enable compression of the HTML just by putting in php.ini:

output_handler = ob_gzhandler

In case, you think about that, then it may take you around 0.1 seconds for generating 40K of the HTML in PHP page. But it most likely takes around 6 seconds for user to download page by using the 56k modem without any compresson. With the compression, download can probably take around 2 to 3 seconds. Thus, time taken for the page generation is miniscule when compared to transit time of HTML from server to browser. Thus, biggest speedup you may perform for the modem users is making use of ob_gzhandler! The feature is just recommended for the PHP 4.1.0 and later.

The point was been moved closer to top of list on 9July 2002 while experienced personally benefits of the compression. The PHP scripts are been recompiled each time till scripts are cached. Install the PHP caching product (and I suggest Turck MMCache) to generally increase the performance by around 25 to 100% just by removing the compile times. Switch from the file based sessions to the shared memory sessions. You can compile the PHP with –with-mm choice as well as set session.save_handler=mm in the php.ini. The informal benchmarks suggest session management time is been halved by simple change.

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Performance Tuning Apache Web Server on Linux – Faster in Both Performance and Access!

April 20th, 2012 No comments

Now, the use of Apache web server of Linux system is high on demand due to its excellent performance and access.  It is also loaded with attractive features that the webmaster can easily access according to the instruction. Like Linux OS system, Apache web server is also easy to access due to simple menus.  It is also never so critical like the Windows NT and UNIX types web server. So, the users are never required more expertise to access it.  It is also required some easy cords that the users can use at the time of operating to boost the server performance.

This can speed up the PHP code by around 5 to 15% in case, you print or else echo in the code. Note output buffering is enabled in case, you are making use of above ob_gzhandler hint. ASP does in IIS. On Windows, the FastCGI is highest performance way to run PHP with the Apache. Though PHP4 will run in the threaded environment, few global locks prevent that from making complete use of the threads. As well PHP is not stable in the threaded environments as a lot of common extensions aren’t thread safe.  In PHP4, the objects & arrays must get passed in & out of the functions by reference and everything by value. In the PHP5, objects are passed automatically by the reference. Example following gives good performance:

function &test(&$obj_or_array)

{

return $obj_or_array;

}

$var =& test($obj);

Be miserly & sparse with the server as well as web pages. Do not run XWindows on server as well as other unneeded processes. The Apache Today has guide on how you can remove them. Also, added 1 Dec 2001 and this hint must just get used for the PHP 4.2.0 as well as above there were the bugs before this. The alternative caching method while you have the pages that do not change very frequently is cache HTML output of the PHP pages and try Smarty or else Cache Lite. Make use of  output buffering.

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