Thursday, August 13, 2015

Solaris 10 - `host` and `nslookup` resolves hostnames while `ping` and `telnet` does not?

  • /etc/resolv.conf contains a nameserver that is alive (as reported by the ping command)
  • host or nslookup is able to resolve google.com

    $ host google.com
    google.com has address 74.125.228.3
    google.com has address 74.125.228.4
    ...
    $ nslookup google.com
    ...
    Non-authorative answer:
    Name:   google.com
    Address: 74.125.228.0
    Name:   google.com
    Address: 74.125.228.1
    ..
     
  • ping or telnet is not able to resolve google.com

    $ ping google.com
    ping: unknown host google.com
    
    $ telnet google.com
    google.com: node name or service name not known
     
     
    Fix Solution:
     
    Your /etc/nsswitch.conf should have an entry like this:
    
    hosts:  files dns
    
    
    
    This tells the Solaris Naming Service that hosts should be looked up first in the local file (i.e. /etc/hosts) and then in DNS. You can of course also only have "dns" here but people will normally want it so that /etc/hosts can override what is in DNS.

    You may now have to restart the naming service daemon:
    $svcadm restart /system/name-service-cache
     

Solaris 10 - Configure a Physical Ethernet Interface After System Installation

  1. On the system with the interfaces to be configured, assume the Primary Administrator role or become superuser.
    The Primary Administrator role includes the Primary Administrator profile. To create the role and assign the role to a user, see Chapter 2, Working With the Solaris Management Console (Tasks), in System Administration Guide: Basic Administration.
  2. Determine which interfaces are currently installed on the system.

    # dladm show-link  
  3.  Configure and plumb each interface.

    # ifconfig interface plumb up
    

    For example, for qfe0 you would type:

    # ifconfig qfe0 plumb up
    

    Note: Interfaces that are explicitly configured with the ifconfig command do not persist across a reboot.

  4. Assign an IPv4 address and netmask to the interface.

    # ifconfig interface IPv4-address netmask+netmask
    
    For example, for qfe0 you would type:

    # ifconfig
    qfe0 192.168.84.3 netmask + 255.255.255.0
    

    Note: You can specify an IPv4 address in either traditional IPv4 notation or CIDR notation.

  5. Verify that the newly configured interfaces are plumbed and configured, or “UP.”

    # ifconfig
    -a
    
    Check the status line for each interface that is displayed. Ensure that the output contains an UP flag on the status line, for example:

    qfe0: flags=1000843 <UP,BROADCAST,RUNNING,MULTICAST,IPv4>
    mtu 1500 index 2
  6. (Optional) To make the interface configuration persist across reboots, perform the following steps:
    1. Create an /etc/hostname.interface file for each interface to be configured.
      For example, to add a qfe0 interface, you would create the following file:

      # vi /etc/hostname.qfe0
      

      Note – If you create alternate hostname files for the same interface, the alternate files must also follow the naming format hostname.[0–9]*, such as hostname.qfe0.a123. Names such as hostname.qfe0.bak or hostname.qfe0.old are invalid and will be ignored by scripts during system boot.
      Note, too, that a given interface must have only one corresponding hostname file. If you create an alternate hostname file for an interface with a valid filename, such as /etc/hostname.qfe and /etc/hostname.qfe.a123, the boot scripts will attempt to configure by referencing the contents of both hostname files and would therefore generate errors. To prevent these errors, provide an invalid file name to the hostname file that you do not want to use in a given configuration.

    2. Edit the /etc/hostname.interface file.
      At a minimum, add the IPv4 address of the interface to the file. You can use traditional IPv4 notation or CIDR notation to specify the IP address of the interface. You can also add a netmask and other configuration information to the file.

      Note – To add an IPv6 address to an interface, refer to Modifying an IPv6 Interface Configuration for Hosts and Servers

    3. For Solaris 10 11/06 and earlier releases of Oracle Solaris 10, add entries for the new interfaces into the /etc/inet/ipnodes file.
    4. Add entries for the new interfaces into the /etc/inet/hosts file.
    5. Perform a reconfiguration boot.

      # reboot -- -r
      
    6. Verify that the interface you created in the /etc/hostname.interface file has been configured.

      # ifconfig -a
      
      For examples, refer to Example 6–2.

Example 6–2 Adding Persistent Interface Configurations
The example shows how to configure the interfaces qfe0 and qfe1 to a host. These interfaces remain persistent across reboots.


# dladm show-link
eri0    type: legacy    mtu: 1500       device: eri0 
qfe0    type: legacy    mtu: 1500       device: qfe0 
qfe1    type: legacy    mtu: 1500       device: qfe1 
qfe2    type: legacy    mtu: 1500       device: qfe2 
qfe3    type: legacy    mtu: 1500       device: qfe3 
bge0    type: non-vlan  mtu: 1500       device: bge0
# vi /etc/hostname.qfe0
192.168.84.3 netmask 255.255.255.0
# vi /etc/hostname.qfe1 
192.168.84.72 netmask 255.255.255.0
# vi /etc/inet/hosts
# Internet host table 
# 
127.0.0.1       localhost 
10.0.0.14       myhost
192.168.84.3       interface-2 
192.168.84.72       interface-3
For Solaris 10 11/06 and earlier releases:# vi /etc/inet/ipnodes
10.0.0.14 myhost
192.168.84.3       interface-2 
192.168.84.72       interface-3

At this point, you would reboot the system.

# reboot -- -r

After the system boots, you would then verify the interface configuration.

ifconfig -a
# ifconfig -a lo0: flags=1000849 <UP,LOOPBACK,RUNNING,MULTICAST,IPv4> mtu
8232 index 1
         inet 127.0.0.1 netmask ff000000  
eri0: flags=1000843<UP,BROADCAST,RUNNING,MULTICAST,IPv4> mtu 1500 index 2
         inet 10.0.0.14netmask ff000000 broadcast 10.255.255.255
         ether 8:0:20:c1:8b:c3  
qfe0:flags=1000843 <UP,BROADCAST,RUNNING,MULTICAST,IPv4> mtu 1500 index 3  
      inet 192.168.84.3 netmask ffffff00 broadcast 192.255.255.255
      ether 8:0:20:c8:f4:1d  
qfe1: flags=1000843 <UP,BROADCAST,RUNNING,MULTICAST,IPv4>mtu 1500 index 4
         inet 192.168.84.72 netmask ffffff00 broadcast 10.255.255.255
        ether 8:0:20:c8:f4:1e 

Tuesday, August 11, 2015

Install Firefox 39 on CentOS, Ubuntu & Other Linux Systems

Remove Existing Version’s

First remove any existing version of Firefox from your system if installed using rpm. Redhat based system use following command.
# yum remove firefox

Downloading Latest Firefox Archive

Download the latest Firefox archive from here (32 bit) and here (64 bit). At the time of last update of this article Firefox 39 is the latest version available. Download Firefox 39 source code as per your system architecture using one of following commands.

32-Bit Systems

# cd /usr/local
# wget http://ftp.mozilla.org/pub/mozilla.org/firefox/releases/39.0/linux-i686/en-US/firefox-39.0.tar.bz2

64-Bit Systems

# cd /usr/local
# wget http://ftp.mozilla.org/pub/mozilla.org/firefox/releases/39.0/linux-x86_64/en-US/firefox-39.0.tar.bz2

Extract Archive on System

After downloading latest version of Firefox archive on your system, let’s extract is using following command.
# tar xvjf firefox-39.0.tar.bz2

Configure Firefox

Firefox source is completely pre compiled and we don’t have to do anything to make it running on system. We just need to create a soft-link of Firefox binary file to systems bin directory to make it accessible from anywhere in system.
# ln -s /usr/local/firefox/firefox /usr/bin/firefox

Now start Firefox using following command from Linux terminal.
# firefox &

Wednesday, August 5, 2015

TAR Commands,examples for Linux

1. Create tar Archive File

The below example command will create a tar archive file tecmint-14-09-12.tar for a directory /home/tecmint in current working directory. See the example command in action.
# tar -cvf tecmint-14-09-12.tar /home/tecmint/

/home/tecmint/
/home/tecmint/cleanfiles.sh
/home/tecmint/openvpn-2.1.4.tar.gz
/home/tecmint/tecmint-14-09-12.tar
/home/tecmint/phpmyadmin-2.11.11.3-1.el5.rf.noarch.rpm
/home/tecmint/rpmforge-release-0.5.2-2.el5.rf.i386.rpm
Let’s discuss the each option we have used in the above command for creating tar archive file.
  1. c – Creates a new .tar archive file.
  2. v – Verbosely show the .tar file progress.
  3. f – File name type of the archive file.

2. Create tar.gz Archive File

To create a compressed gzip archive file we use the option as z. For example the below command will create a compressed MyImages-14-09-12.tar.gz file for the directory /home/MyImages. (Note : tar.gz and tgz both are similar).
# tar cvzf MyImages-14-09-12.tar.gz /home/MyImages
OR
# tar cvzf MyImages-14-09-12.tgz /home/MyImages

/home/MyImages/
/home/MyImages/Sara-Khan-and-model-Priyanka-Shah.jpg
/home/MyImages/RobertKristenviolent101201.jpg
/home/MyImages/Justintimerlake101125.jpg
/home/MyImages/Mileyphoto101203.jpg
/home/MyImages/JenniferRobert101130.jpg
/home/MyImages/katrinabarbiedoll231110.jpg
/home/MyImages/the-japanese-wife-press-conference.jpg
/home/MyImages/ReesewitherspoonCIA101202.jpg
/home/MyImages/yanaguptabaresf231110.jpg

3. Create tar.bz2 Archive File

The bz2 feature compress and create archive file less than the size of the gzip. The bz2 compression takes more time to compress and decompress files as compared to gzip which takes less time. To create highly compressed tar file we use option as j. The following example of command will create a Phpfiles-org.tar.bz2 file for a directory /home/php. (Note: tar.bz2 and tbz is similar as tb2).
# tar cvfj Phpfiles-org.tar.bz2 /home/php
OR
# tar cvfj Phpfiles-org.tar.tbz /home/php
OR 
# tar cvfj Phpfiles-org.tar.tb2 /home/php

/home/php/
/home/php/iframe_ew.php
/home/php/videos_all.php
/home/php/rss.php
/home/php/index.php
/home/php/vendor.php
/home/php/video_title.php
/home/php/report.php
/home/php/object.html
/home/php/video.php

4. Untar tar Archive File

To untar or extract a tar file, just issue following command using option x (extract). For example the below command will untar the file public_html-14-09-12.tar in present working directory. If you want untar in a different directory then use option as -C (specified directory).
## Untar files in Current Directory ##
# tar -xvf public_html-14-09-12.tar

## Untar files in specified Directory ##
# tar -xvf public_html-14-09-12.tar -C /home/public_html/videos/

/home/public_html/videos/
/home/public_html/videos/views.php
/home/public_html/videos/index.php
/home/public_html/videos/logout.php
/home/public_html/videos/all_categories.php
/home/public_html/videos/feeds.xml

5. Uncompress tar.gz Archive File

To Uncompress tar.gz archive file, just run following command. If would like to untar in different directory just use option -C and the path of the directory,  like we shown in the above example.
# tar -xvf thumbnails-14-09-12.tar.gz

/home/public_html/videos/thumbnails/
/home/public_html/videos/thumbnails/katdeepika231110.jpg
/home/public_html/videos/thumbnails/katrinabarbiedoll231110.jpg
/home/public_html/videos/thumbnails/onceuponatime101125.jpg
/home/public_html/videos/thumbnails/playbutton.png
/home/public_html/videos/thumbnails/ReesewitherspoonCIA101202.jpg
/home/public_html/videos/thumbnails/snagItNarration.jpg
/home/public_html/videos/thumbnails/Minissha-Lamba.jpg
/home/public_html/videos/thumbnails/Lindsaydance101201.jpg
/home/public_html/videos/thumbnails/Mileyphoto101203.jpg

6. Uncompress tar.bz2 Archive File

To Uncompress highly compressed tar.bz2 file, just use the following command. The below example command will untar all the .flv files from the archive file.
# tar -xvf videos-14-09-12.tar.bz2

/home/public_html/videos/flv/katrinabarbiedoll231110.flv
/home/public_html/videos/flv/BrookmuellerCIA101125.flv
/home/public_html/videos/flv/dollybackinbb4101125.flv
/home/public_html/videos/flv/JenniferRobert101130.flv
/home/public_html/videos/flv/JustinAwardmovie101125.flv
/home/public_html/videos/flv/Lakme-Fashion-Week.flv
/home/public_html/videos/flv/Mileyphoto101203.flv
/home/public_html/videos/flv/Minissha-Lamba.flv

7. List Content of tar Archive File

To list the content of tar archive file, just run the following command with option t (list content). The below command will list the content of uploadprogress.tar file.
# tar -tvf uploadprogress.tar

-rw-r--r-- chregu/staff   2276 2011-08-15 18:51:10 package2.xml
-rw-r--r-- chregu/staff   7877 2011-08-15 18:51:10 uploadprogress/examples/index.php
-rw-r--r-- chregu/staff   1685 2011-08-15 18:51:10 uploadprogress/examples/server.php
-rw-r--r-- chregu/staff   1697 2011-08-15 18:51:10 uploadprogress/examples/info.php
-rw-r--r-- chregu/staff    367 2011-08-15 18:51:10 uploadprogress/config.m4
-rw-r--r-- chregu/staff    303 2011-08-15 18:51:10 uploadprogress/config.w32
-rw-r--r-- chregu/staff   3563 2011-08-15 18:51:10 uploadprogress/php_uploadprogress.h
-rw-r--r-- chregu/staff  15433 2011-08-15 18:51:10 uploadprogress/uploadprogress.c
-rw-r--r-- chregu/staff   1433 2011-08-15 18:51:10 package.xml

8. List Content tar.gz Archive File

Use the following command to list the content of tar.gz file.
# tar -tvf staging.tecmint.com.tar.gz

-rw-r--r-- root/root         0 2012-08-30 04:03:57 staging.tecmint.com-access_log
-rw-r--r-- root/root       587 2012-08-29 18:35:12 staging.tecmint.com-access_log.1
-rw-r--r-- root/root       156 2012-01-21 07:17:56 staging.tecmint.com-access_log.2
-rw-r--r-- root/root       156 2011-12-21 11:30:56 staging.tecmint.com-access_log.3
-rw-r--r-- root/root       156 2011-11-20 17:28:24 staging.tecmint.com-access_log.4
-rw-r--r-- root/root         0 2012-08-30 04:03:57 staging.tecmint.com-error_log
-rw-r--r-- root/root      3981 2012-08-29 18:35:12 staging.tecmint.com-error_log.1
-rw-r--r-- root/root       211 2012-01-21 07:17:56 staging.tecmint.com-error_log.2
-rw-r--r-- root/root       211 2011-12-21 11:30:56 staging.tecmint.com-error_log.3
-rw-r--r-- root/root       211 2011-11-20 17:28:24 staging.tecmint.com-error_log.4

9. List Content tar.bz2 Archive File

To list the content of tar.bz2 file, issue the following command.
# tar -tvf Phpfiles-org.tar.bz2

drwxr-xr-x root/root         0 2012-09-15 03:06:08 /home/php/
-rw-r--r-- root/root      1751 2012-09-15 03:06:08 /home/php/iframe_ew.php
-rw-r--r-- root/root     11220 2012-09-15 03:06:08 /home/php/videos_all.php
-rw-r--r-- root/root      2152 2012-09-15 03:06:08 /home/php/rss.php
-rw-r--r-- root/root      3021 2012-09-15 03:06:08 /home/php/index.php
-rw-r--r-- root/root      2554 2012-09-15 03:06:08 /home/php/vendor.php
-rw-r--r-- root/root       406 2012-09-15 03:06:08 /home/php/video_title.php
-rw-r--r-- root/root      4116 2012-09-15 03:06:08 /home/php/report.php
-rw-r--r-- root/root      1273 2012-09-15 03:06:08 /home/php/object.html

10. Untar Single file from tar File

To extract a single file called cleanfiles.sh from cleanfiles.sh.tar use the following command.
# tar -xvf cleanfiles.sh.tar cleanfiles.sh
OR
# tar --extract --file=cleanfiles.sh.tar cleanfiles.sh

cleanfiles.sh

11. Untar Single file from tar.gz File

To extract a single file tecmintbackup.xml from tecmintbackup.tar.gz archive file, use the command as follows.
# tar -zxvf tecmintbackup.tar.gz tecmintbackup.xml
OR
# tar --extract --file=tecmintbackup.tar.gz tecmintbackup.xml

tecmintbackup.xml

12. Untar Single file from tar.bz2 File

To extract a single file called index.php from the file Phpfiles-org.tar.bz2 use the following option.
# tar -jxvf Phpfiles-org.tar.bz2 home/php/index.php
OR
# tar --extract --file=Phpfiles-org.tar.bz2 /home/php/index.php

/home/php/index.php

13. Untar Multiple files from tar, tar.gz and tar.bz2 File

To extract or untar multiple files from the tar, tar.gz and tar.bz2 archive file. For example the below command will extract “file 1” “file 2” from the archive files.
# tar -xvf tecmint-14-09-12.tar "file 1" "file 2" 

# tar -zxvf MyImages-14-09-12.tar.gz "file 1" "file 2" 

# tar -jxvf Phpfiles-org.tar.bz2 "file 1" "file 2"

14. Extract Group of Files using Wildcard

To extract a group of files we use wildcard based extracting. For example, to extract a group of all files whose pattern begins with .php from a tar, tar.gz and tar.bz2 archive file.
# tar -xvf Phpfiles-org.tar --wildcards '*.php'

# tar -zxvf Phpfiles-org.tar.gz --wildcards '*.php'

# tar -jxvf Phpfiles-org.tar.bz2 --wildcards '*.php'

/home/php/iframe_ew.php
/home/php/videos_all.php
/home/php/rss.php
/home/php/index.php
/home/php/vendor.php
/home/php/video_title.php
/home/php/report.php
/home/php/video.php

15. Add Files or Directories to tar Archive File

To add files or directories to existing tar archived file we use the option r (append). For example we add file xyz.txt and directory php to existing tecmint-14-09-12.tar archive file.
# tar -rvf tecmint-14-09-12.tar xyz.txt

# tar -rvf tecmint-14-09-12.tar php

drwxr-xr-x root/root         0 2012-09-15 02:24:21 home/tecmint/
-rw-r--r-- root/root  15740615 2012-09-15 02:23:42 home/tecmint/cleanfiles.sh
-rw-r--r-- root/root    863726 2012-09-15 02:23:41 home/tecmint/openvpn-2.1.4.tar.gz
-rw-r--r-- root/root  21063680 2012-09-15 02:24:21 home/tecmint/tecmint-14-09-12.tar
-rw-r--r-- root/root   4437600 2012-09-15 02:23:41 home/tecmint/phpmyadmin-2.11.11.3-1.el5.rf.noarch.rpm
-rw-r--r-- root/root     12680 2012-09-15 02:23:41 home/tecmint/rpmforge-release-0.5.2-2.el5.rf.i386.rpm
-rw-r--r-- root/root 0 2012-08-18 19:11:04 xyz.txt
drwxr-xr-x root/root 0 2012-09-15 03:06:08 php/ 
-rw-r--r-- root/root 1751 2012-09-15 03:06:08 php/iframe_ew.php 
-rw-r--r-- root/root 11220 2012-09-15 03:06:08 php/videos_all.php 
-rw-r--r-- root/root 2152 2012-09-15 03:06:08 php/rss.php 
-rw-r--r-- root/root 3021 2012-09-15 03:06:08 php/index.php 
-rw-r--r-- root/root 2554 2012-09-15 03:06:08 php/vendor.php 
-rw-r--r-- root/root 406 2012-09-15 03:06:08 php/video_title.php

16. Add Files or Directories to tar.gz and tar.bz2 files

The tar command don’t have a option to add files or directories to a existing compressed tar.gz and tar.bz2 archive file. If we do try will get tbe following error.
# tar -rvf MyImages-14-09-12.tar.gz xyz.txt

# tar -rvf Phpfiles-org.tar.bz2 xyz.txt

tar: This does not look like a tar archive
tar: Skipping to next header
xyz.txt
tar: Error exit delayed from previous errors

17. How To Verify tar, tar.gz and tar.bz2 Archive File

To verfify any tar or compressed archived file we use option as W (verify). To do, just use the following examples of command. (Note : You cannot do verification on a compressed ( *.tar.gz, *.tar.bz2 ) archive file).
# tar tvfW tecmint-14-09-12.tar

tar: This does not look like a tar archive
tar: Skipping to next header
tar: Archive contains obsolescent base-64 headers
tar: VERIFY FAILURE: 30740 invalid headers detected
Verify -rw-r--r-- root/root    863726 2012-09-15 02:23:41 /home/tecmint/openvpn-2.1.4.tar.gz
Verify -rw-r--r-- root/root  21063680 2012-09-15 02:24:21 /home/tecmint/tecmint-14-09-12.tar
tar: /home/tecmint/tecmint-14-09-12.tar: Warning: Cannot stat: No such file or directory
Verify -rw-r--r-- root/root   4437600 2012-09-15 02:23:41 home/tecmint/phpmyadmin-2.11.11.3-1.el5.rf.noarch.rpm
tar: /home/tecmint/phpmyadmin-2.11.11.3-1.el5.rf.noarch.rpm: Warning: Cannot stat: No such file or directory
Verify -rw-r--r-- root/root     12680 2012-09-15 02:23:41 home/tecmint/rpmforge-release-0.5.2-2.el5.rf.i386.rpm
tar: /home/tecmint/rpmforge-release-0.5.2-2.el5.rf.i386.rpm: Warning: Cannot stat: No such file or directory
Verify -rw-r--r-- root/root         0 2012-08-18 19:11:04 xyz.txt
Verify drwxr-xr-x root/root         0 2012-09-15 03:06:08 php/

18. Check the Size of the tar, tar.gz and tar.bz2 Archive File

To check the size of any tar, tar.gz and tar.bz2 archive file, use the following command. For example the below command will display the size of archvie file in Kilobytes (KB).
# tar -czf - tecmint-14-09-12.tar | wc -c
12820480

# tar -czf - MyImages-14-09-12.tar.gz | wc -c
112640

# tar -czf - Phpfiles-org.tar.bz2 | wc -c
20480

Monday, August 3, 2015

RPM Commands, examples for Linux

There are five basic modes for RPM command

  1. Install : It is used to install any RPM package.
  2. Remove : It is used to erase, remove or un-install any RPM package.
  3. Upgrade : It is used to update the existing RPM package.
  4. Verify : It is used to query about different RPM packages.
  5. Query : It is used for the verification of any RPM package.

Where to find RPM packages

Below is the list of rpm sites, where you can find and download all RPM packages.
  1. http://rpmfind.net
  2. http://www.redhat.com
  3. http://freshrpms.net/
  4. http://rpm.pbone.net/

1. How to Check an RPM Signature Package

Always check the PGP signature of packages before installing them on your Linux systems and make sure its integrity and origin is OK. Use the following command with –checksig (check signature) option to check the signature of a package called pidgin.
[root@tecmint]# rpm --checksig pidgin-2.7.9-5.el6.2.i686.rpm

pidgin-2.7.9-5.el6.2.i686.rpm: rsa sha1 (md5) pgp md5 OK
 

2. How to Install an RPM Package

For installing an rpm software package, use the following command with -i option. For example, to install an rpm package called pidgin-2.7.9-5.el6.2.i686.rpm.
[root@tecmint]# rpm -ivh pidgin-2.7.9-5.el6.2.i686.rpm Preparing... ########################################### [100%] 1:pidgin ########################################### [100%]
RPM command and options
  1. -i : install a package
  2. -v : verbose for a nicer display
  3. -h: print hash marks as the package archive is unpacked.

3. How to check dependencies of RPM Package before Installing

Let’s say you would like to do a dependency check before installing or upgrading a package. For example, use the following command to check the dependencies of BitTorrent-5.2.2-1-Python2.4.noarch.rpm package. It will display the list of dependencies of package.
[root@tecmint]# rpm -qpR BitTorrent-5.2.2-1-Python2.4.noarch.rpm /usr/bin/python2.4 python >= 2.3 python(abi) = 2.4 python-crypto >= 2.0 python-psyco python-twisted >= 2.0 python-zopeinterface rpmlib(CompressedFileNames) = 2.6
RPM command and options
  1. -q : Query a package
  2. -p : List capabilities this package provides.
  3. -R: List capabilities on which this package depends..

4. How to Install a RPM Package Without Dependencies

If you know that all needed packages are already installed and RPM is just being stupid, you can ignore those dependencies by using the option –nodeps (no dependencies check) before installing the package.
[root@tecmint]# rpm -ivh --nodeps BitTorrent-5.2.2-1-Python2.4.noarch.rpm Preparing... ########################################### [100%] 1:BitTorrent ########################################### [100%] The above command forcefully install
rpm package by ignoring dependencies errors, but if those dependency files are missing, then the program will not work at all, until you install them.

5. How to check an Installed RPM Package

Using -q option with package name, will show whether an rpm installed or not.
[root@tecmint]# rpm -q BitTorrent BitTorrent-5.2.2-1.noarch

6. How to List all files of an installed RPM package

To view all the files of an installed rpm packages, use the -ql (query list) with rpm command.
[root@tecmint]# rpm -ql BitTorrent /usr/bin/bittorrent /usr/bin/bittorrent-console /usr/bin/bittorrent-curses /usr/bin/bittorrent-tracker /usr/bin/changetracker-console /usr/bin/launchmany-console /usr/bin/launchmany-curses /usr/bin/maketorrent /usr/bin/maketorrent-console /usr/bin/torrentinfo-console

7. How to List Recently Installed RPM Packages

Use the following rpm command with -qa (query all) option, will list all the recently installed rpm packages.
[root@tecmint]# rpm -qa --last BitTorrent-5.2.2-1.noarch Tue 04 Dec 2012 05:14:06 PM BDT pidgin-2.7.9-5.el6.2.i686 Tue 04 Dec 2012 05:13:51 PM BDT cyrus-sasl-devel-2.1.23-13.el6_3.1.i686 Tue 04 Dec 2012 04:43:06 PM BDT cyrus-sasl-2.1.23-13.el6_3.1.i686 Tue 04 Dec 2012 04:43:05 PM BDT cyrus-sasl-md5-2.1.23-13.el6_3.1.i686 Tue 04 Dec 2012 04:43:04 PM BDT cyrus-sasl-plain-2.1.23-13.el6_3.1.i686 Tue 04 Dec 2012 04:43:03 PM BDT

8. How to List All Installed RPM Packages

Type the following command to print the all the names of installed packages on your Linux system.
[root@tecmint]# rpm -qa initscripts-9.03.31-2.el6.centos.i686 polkit-desktop-policy-0.96-2.el6_0.1.noarch thunderbird-17.0-1.el6.remi.i686

9. How to Upgrade a RPM Package

If we want to upgrade any RPM package “–U” (upgrade) option will be used. One of the major advantages of using this option is that it will not only upgrade the latest version of any package, but it will also maintain the backup of the older package so that in case if the newer upgraded package does not run the previously installed package can be used again.
[root@tecmint]# rpm -Uvh nx-3.5.0-2.el6.centos.i686.rpm Preparing... ########################################### [100%] 1:nx ########################################### [100%]

10. How to Remove a RPM Package

To un-install an RPM package, for example we use the package name nx, not the original package name nx-3.5.0-2.el6.centos.i686.rpm. The -e (erase) option is used to remove package.
[root@tecmint]# rpm -evv nx

11. How to Remove an RPM Package Without Dependencies

The –nodeps (Do not check dependencies) option forcefully remove the rpm package from the system. But keep in mind removing particular package may break other working applications.
[root@tecmint]# rpm -ev --nodeps vsftpd

12. How to Query a file that belongs which RPM Package

Let’s say, you have list of files and you would like to find out which package belongs to these files. For example, the following command with -qf (query file) option will show you a file /usr/bin/htpasswd is own by package httpd-tools-2.2.15-15.el6.centos.1.i686.
[root@tecmint]# rpm -qf /usr/bin/htpasswd httpd-tools-2.2.15-15.el6.centos.1.i686

13. How to Query a Information of Installed RPM Package

Let’s say you have installed an rpm package and want to know the information about the package. The following -qi (query info) option will print the available information of the installed package.
[root@tecmint]# rpm -qi vsftpd Name : vsftpd Relocations: (not relocatable) Version : 2.2.2 Vendor: CentOS Release : 11.el6 Build Date: Fri 22 Jun 2012 01:54:24 PM BDT Install Date: Mon 17 Sep 2012 07:55:28 PM BDT Build Host: c6b8.bsys.dev.centos.org Group : System Environment/Daemons Source RPM: vsftpd-2.2.2-11.el6.src.rpm Size : 351932 License: GPLv2 with exceptions Signature : RSA/SHA1, Mon 25 Jun 2012 04:07:34 AM BDT, Key ID 0946fca2c105b9de Packager : CentOS BuildSystem <http://bugs.centos.org> URL : http://vsftpd.beasts.org/ Summary : Very Secure Ftp Daemon Description : vsftpd is a Very Secure FTP daemon. It was written completely from scratch.

14. Get the Information of RPM Package Before Installing

You have download a package from the internet and want to know the information of a package before installing. For example, the following option -qip (query info package) will print the information of a package sqlbuddy.
[root@tecmint]# rpm -qip sqlbuddy-1.3.3-1.noarch.rpm Name : sqlbuddy Relocations: (not relocatable) Version : 1.3.3 Vendor: (none) Release : 1 Build Date: Wed 02 Nov 2011 11:01:21 PM BDT Install Date: (not installed) Build Host: rpm.bar.baz Group : Applications/Internet Source RPM: sqlbuddy-1.3.3-1.src.rpm Size : 1155804 License: MIT Signature : (none) Packager : Erik M Jacobs URL : http://www.sqlbuddy.com/ Summary : SQL Buddy รข Web based MySQL administration Description : SQLBuddy is a PHP script that allows for web-based MySQL administration.

15. How to Query documentation of Installed RPM Package

To get the list of available documentation of an installed package, use the following command with option -qdf (query document file) will display the manual pages related to vmstat package.
[root@tecmint]# rpm -qdf /usr/bin/vmstat /usr/share/doc/procps-3.2.8/BUGS /usr/share/doc/procps-3.2.8/COPYING /usr/share/doc/procps-3.2.8/COPYING.LIB /usr/share/doc/procps-3.2.8/FAQ /usr/share/doc/procps-3.2.8/NEWS /usr/share/doc/procps-3.2.8/TODO

16. How to Verify a RPM Package

Verifying a package compares information of installed files of the package against the rpm database. The -Vp (verify package) is used to verify a package.
[root@tecmint downloads]# rpm -Vp sqlbuddy-1.3.3-1.noarch.rpm S.5....T. c /etc/httpd/conf.d/sqlbuddy.conf

17. How to Verify all RPM Packages

Type the following command to verify all the installed rpm packages.
[root@tecmint]# rpm -Va S.5....T. c /etc/rc.d/rc.local .......T. c /etc/dnsmasq.conf .......T. /etc/ld.so.conf.d/kernel-2.6.32-279.5.2.el6.i686.conf S.5....T. c /etc/yum.conf S.5....T. c /etc/yum.repos.d/epel.repo

18. How to Import an RPM GPG key

To verify RHEL/CentOS/Fedora packages, you must import the GPG key. To do so, execute the following command. It will import CentOS 6 GPG key.
[root@tecmint]# rpm --import /etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-6

19. How to List all Imported RPM GPG keys

To print all the imported GPG keys in your system, use the following command.
[root@tecmint]# rpm -qa gpg-pubkey* gpg-pubkey-0608b895-4bd22942 gpg-pubkey-7fac5991-4615767f gpg-pubkey-0f2672c8-4cd950ee gpg-pubkey-c105b9de-4e0fd3a3 gpg-pubkey-00f97f56-467e318a gpg-pubkey-6b8d79e6-3f49313d gpg-pubkey-849c449f-4cb9df30

20. How To rebuild Corrupted RPM Database

Sometimes rpm database gets corrupted and stops all the functionality of rpm and other applications on the system. So, at the time we need to rebuild the rpm database and restore it with the help of following command.
[root@tecmint]# cd /var/lib [root@tecmint]# rm __db* [root@tecmint]# rpm --rebuilddb [root@tecmint]# rpmdb_verify Packages