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Showing posts with label Linux. Show all posts
Showing posts with label Linux. Show all posts

Friday, May 10, 2019

Linux SysAdmin] 2. What is a server?

People who are interested in server hardware maybe have thought about it once. 'What is a server?' A server is a device or software that provides a service. 

For example, you might be using a Wi-Fi router at home. When you get home, your smartphone will automatically get an IP address from it and you will use the Internet through it. So what service does the Wi-Fi router provide for your smartphone? 

It is a DHCP service. The Wi-Fi Router acts as a DHCP server and your smartphone as a DHCP client. In other words, the DHCP server software is installed on your Wi-Fi router and the DHCP client software is installed on your smartphone. A client is a device or software that accesses a service provided by a server. 

In general, when people hear the server, they will think of the following hardware:


But a device that provides a service can be called a server.

What is different between a server and a desktop?

Anyway, let's take a look at the server. How is it different from the desktop you use at home?

The first is a price difference. The server is more expensive than the desktop. In general, servers use larger and more expensive components than desktop. For Example, the following kinds of CPU are installed within the x86 desktop and the x86 server.

Desktop
x86 Server
 - Intel Core X Processor
 - AMD Ryzen Processor
 - Intel Xeon E Processor
 - AMD EPYC Processors


What companies are the x86 server manufacturer? HP, Dell, Fujitsu, Lenovo, Gigabyte, ASUS, Tyan, Supermicro and so on. Examples of Unix server CPUs are IBM Power CPU and Oracle SPARC CPU. Have you ever thought about how expensive a server CPU would be?



The second is performance. The desktop usually uses a single CPU. But the server can use multiple CPUs. The Intel Xeon E5 product support two and four-socket systems. And The Intel Xeon E7 product support from two to eight sockets. Unix processor product support up to dozens of sockets systems.

How much memory supported per CPU?

Intel Core i9
Intel Xeon Platinum 9282
AMD EPYC 7601
 128GB
 2TB
 2TB

How many cores supported per CPU?

Intel Core i9
Intel Xeon Platinum 9282
AMD EPYC 7601
 16
 56
 32

How peaceful will be the programs running on a system with 4TB memory? I would like to use such a system. :D

The third is the availability. You will turn off your desktop when work is finish, but the server should be stable 24/7. Servers are designed to provide reliable services in a mission-critical enterprise environment and are typically installed and operating in a data center. Stable power supply, optimum temperature, and humidity maintenance, the dust-free environment is very important.


Certain parts of the server are modular and are designed to be easily replaceable if they fail. Also, it has a fault-tolerant structure. For example, the power supply has an N + 1 structure. So even if one power supply fails, the server service goes back to normal.

The fourth is scalability. After the server is installed, it is likely that the service will gradually increase over time. Depending on the service load, CPU power may be needed more and there may be insufficient memory size for applications or storage capacity for data. At the point, the server should be able to be scalable enough for the resources you need.


For example, suppose you installed an FC HBA card on a server and then connected it to a SAN network and allocated a certain amount of external storage space for storing data. When storage space runs out at some point over time, it must be able to increase external storage capacity and allocate additional space to servers without rebooting.

So far, you've looked at the features of the server.

I am not familiar with English yet and I don't know if it was explained well. It will improve gradually. So see you next post. Thank you.



Tuesday, May 7, 2019

Linux SysAdmin] 1. Starting Linux SysAdmin

Hello, guys. Over the next few weeks, I will post how to manage Linux. Linux is one of the operating systems installed and operated on many servers. There are various Linux operating systems such as Red Hat Enterprise Linux, SUSE Linux Enterprise Server, Fedora, CentOS, Ubuntu and so on. Among these operating systems, I will post about how to manage CentOS and Ubuntu.


Linux is installed and running on a wide variety of hardware and maybe you see servers with an Intel or AMD CPU(s). The above picture is Fujitsu PRIMERGY RX300 S8 server with dual Intel Xeon E5 CPU. We bought this server 4 years ago and it is still working without any problem. I installed Ubuntu Linux at that time and it is still in good use. You can see what the inside of the server looks like from the photo above. Middle or high-end servers are more complex.

Using a physical server for personal learning is costly. Because it costs thousands to tens of thousands of dollars per server. If you want to test the network, you need several servers. So how much money do you need for the test?

Don't worry. With virtualization technology, you can create and use multiple virtual machines on your computer. So I posted several posts about VMware Workstation Pro. It is hosted hypervisor to do intuitive and easy to use. The disadvantage is that it is commercial software. But it will be cheaper than the value of technology that can be acquired through it.

If you don't know how to use VMware Workstation Pro, please refer the following post.

https://sunguruitchannel01.blogspot.com/2013/12/categories-quick-link.html

In the next post, you will know what the server is.

See you next. Thank you.


Thursday, May 4, 2017

How to install CentOS 7.3 Linux on a Virtual Machine in VMware Workstation Pro 12.5

Linux has become a popular operating system. Linux is installed and used in various systems, from desktop to high-performance server. CentOS is a kind of Linux., which is installed on the server, is used for various services such as the web, web application, database, mail and so on.

You can install and test it on a physical server to learn how to use CentOS, but the server is quite expensive. Imagine if you are studying Linux to become an infrastructure engineer. How can you test Linux like CentOS? Nowadays, hardware and software technology has developed a lot. You know this too.

A hypervisor (VMware Workstation, VMware Fusion, VirtualBox, Parallels...) is a useful software that allows anyone without a server to easily test the server operating system. You only need a desktop or laptop to install the hypervisor. We will use VMware Workstation as a hypervisor and it can be installed on Windows or Linux operating systems.

We have already installed Windows 10 with VMware Workstation. And now you will install CentOS 7.3 on a virtual machine using this hypervisor. The virtual machine specification for CentOS 7.3 Linux installation is shown below.

 Hardware
 Requirements
 VM Name
 C01
 CPU
 1 Socket / 2 Core
 Memory
 2GB
 HDD
 20GB
 NIC
 1NIC / NAT

■ Download CentOS 7.3 Linux ISO file

Please, click the hyperlink to download the CentOS 7.3 Linux ISO file.

http://isoredirect.centos.org/centos/7/isos/x86_64/CentOS-7-x86_64-Everything-1611.iso




■ Installing CentOS 7.3 in the virtual machine

Now that you have downloaded the ISO file, let's install CentOS 7.3

- Select the CD / DVD of the virtual machine as shown below and connect the CentOS 7.3 Everything ISO file to the virtual machine.


- Select 'Power on this virtual machine'.


- When the Console View appears as shown below, select 'Install CentOS Linux 7' using up/down arrow buttons and press the Enter key.


- Select your Language and click on the continue button.


- Select Data & Time to set the time zone.


-Set the timezone and click on the Done button.


- Select 'SOFTWARE SELECTION' to set the operating system installation type.


- Select 'Server with GUI' and click on the Done button.


- Select 'INSTALLATION DESTINATION' to select the device which the operating system will be installed.



- Select local disk and click on the Done button.


- Select 'NETWORK & HOSTNAME' to set IP Address and hostname.



- Set the host name and IP address referring to the table and figure below.

 Hostname
 c01
 IP Address
 192.168.80.202
 Netmask
 24
 Gateway
 192.168.80.2
 DNS
 168.126.63.1





- Now, click on the Begin Installation button for CentOS 7.3 installation.


- You can see that the installation progresses in the next screen. Now select 'ROOT PASSWORD' to set the root account password.


- After defining the password, click on the Done button.


- Select 'USER CREATION' to create a generic account.


- After defining the account name and password, click on the Done button.


- Now, be patient and wait a few minutes to complete the installation. :D When the installation is complete, click on the Reboot button.


- After rebooting, the following screen appears. Select 'LICENSE INFORMATION' to set the license agreement.


- Check the check box and click on the Done button.


- Press FINISH CONFIGURATION to exit the installation.


- After the installation is complete, the login screen will appear as shown below.


Well done. In the next post, I will show you how to install VMware Tools on the Guest OS See you next. Bye Bye. :D


Tuesday, December 24, 2013

How to install Ubuntu 12 04 Linux in VMware Workstation

Ubuntu is a famous Linux OS. It is freely available. Many people install and use this OS in their PC, laptop, smartpad. it is one of the widely deployed Linux. You can also install it in VMware Workstation.

Please refer to the following to install Ubuntu Linux.


Thank you~! :)

Thursday, December 19, 2013

Installing Linux CentOS 6.4 on VMware Workstation

If you want to test Linux CentOS on VMware Workstation, first download ISO files of CentOS and install.

■ CentOS 6.4 ISO download website 

http://vault.centos.org/6.4/isos/x86_64/

Please refer to the following for the installation.