how to distinguish between Server and Client versions of Cent OS

[nitinkumar]

I understand ( may be i am wrong !!!) that there is no proper distinction between CentOS client software and server software. Server version
has few more packages installed which are not available in client version. If it is not true, then please inform.

If it is true, then my questions are as follows:-

1) How to determine whether the version i am having is client version OR Server version of CentOS?

2) Which command from shell prompt I should type to know what packages are installed in my OS? e.g. rpm .....??

3) If i do not know the full name of package and i want to know whether it is installed or not, then is there any way to search?

for example, i wanted to see whether nfs package is installed or not on my centOS 7. I typed "$ rpm -q nfs < return>" I got answer as "$ nfs not installed." but when I typed " $ rpm -q nfs-utils <return>" I got message that nfs-utils are available. It means rpm utility looks for complete name
of the package. Hence how to know the full name of the package for searching ???

[jlehtone]

To list (some) packages:

Code: Select all

rpm -qa
rpm -qa nfs\*
yum list installed
yum list installed \*util\*
yum list \*util\*

For the details, see

Code: Select all

man rpm
man yum

There is no "Server version" or "Client version". There is only CentOS.

Each machine has some packages installed. It either has the packages that you need, or doesn't.
If it doesn't, then you install those required packages.

[desertcat]

I understand ( may be i am wrong !!!) that there is no proper distinction between CentOS client software and server software. Server version
has few more packages installed which are not available in client version. If it is not true, then please inform.

If it is true, then my questions are as follows:-

1) How to determine whether the version i am having is client version OR Server version of CentOS?

2) Which command from shell prompt I should type to know what packages are installed in my OS? e.g. rpm .....??

3) If i do not know the full name of package and i want to know whether it is installed or not, then is there any way to search?

for example, i wanted to see whether nfs package is installed or not on my centOS 7. I typed "$ rpm -q nfs < return>" I got answer as "$ nfs not installed." but when I typed " $ rpm -q nfs-utils <return>" I got message that nfs-utils are available. It means rpm utility looks for complete name
of the package. Hence how to know the full name of the package for searching ???

As the previous poster said there is no "client" or "server" version of CentOS, there is only "CentOS", though occasionally you will see specific "spins" which are versions of CentOS that are directed at a particular group of users, thus you have a "Scientific", a "KDE" spin, a "Workstation" spin, etc. When I set up my workstation I set it up to be extremely flexible, so it can work as either a "client" or a "server"; now my buddy has two old computers in his house which he converted into two strict servers: One computer he converted is used as a Timeserver -- that is all it dos is keep accurate time -- the other computer is used simply used as a Print Server. My workstation is a multi-function machinen it can either work as server/s or as client/s. I am a client on my buddy's Timeserver, but need be he can access data from my workstation.

If you want to install nfs-utils simply run yum install nfs-utils. I was pretty sure I had once installed nfs-utils but just for FUN -- and because I can -- I just ran yum install nfs-utils. It came back and said,

" Package 1:nfs-utils-1.3.0-0.66.el7.x86_64 already installed and latest version.
Nothing to do"

Running yum install <package> is a cheap and easy way to find out if it is on your machine. You can always hit N if it has not been installed and you are not sure if you really want to install it. It will however give you a lot of information. If you always use yum update <package> in much the same way.

[MartinR]

Don't overlook yum info. For a package that is already installed:

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$ yum info nfs-utils
Loaded plugins: fastestmirror, langpacks, priorities
Determining fastest mirrors
...
Installed Packages
Name        : nfs-utils
Arch        : x86_64
Epoch       : 1
Version     : 1.3.0
Release     : 0.66.el7
Size        : 1.1 M
Repo        : installed
From repo   : base
Summary     : NFS utilities and supporting clients and daemons for the kernel
            : NFS server
URL         : http://sourceforge.net/projects/nfs
Licence     : MIT and GPLv2 and GPLv2+ and BSD
Description : The nfs-utils package provides a daemon for the kernel NFS server
            : and related tools, which provides a much higher level of
            : performance than the traditional Linux NFS server used by most
            : users.
...

Note that:

• The Repo is shown as "installed"
• The output starts with "Installed Packages".

Now for a package that is not installed:

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$ yum info corosync
...
Available Packages
Name        : corosync
Arch        : x86_64
Version     : 2.4.5
Release     : 4.el7
Size        : 221 k
Repo        : base/7/x86_64
Summary     : The Corosync Cluster Engine and Application Programming Interfaces
URL         : http://corosync.github.io/corosync/
Licence     : BSD
Description : This package contains the Corosync Cluster Engine Executive, several default
            : APIs and libraries, default configuration files, and an init script.

Now the Repo is shown as the source (base/7/x86_64) and the output starts with "Available Packages". Finally a package that doesn't exist:

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$ yum info nfs-utilsZ
...
Error: No matching Packages to list

I would recommend using yum list when searching for a package name since the output is briefer, but then use yum info to ensure that it is the package you want. You can use wildcards with yum info just as others have shown you with yum list but the output may be very lengthy.