Wednesday, March 22, 2017

Sun Solaris zonecfg commands

In the last post, I had explained the usage of zoneadm command for Solaris servers, now in this post we will get the information about the "zonecfg" command. 

This is very useful command which is mostly used during configuration of new zone or installed zone as well as for removal of any zone configuration files.

1. Command for creating a Solaris zone:

Please find the below commands to creating a zone on Sun Solaris server. The command must be run on Global zone with root user.

[sun]#zonecfg -z <zone>

Example: [sun]#zonecfg -z sunz01

Once you run the above command, you can enter in the configuration file, where you can add or edit the configuration for the zone.

2. Command for deleting a Solaris zone:

Please find the below command to deleting a Solaris zone from Global zone.

[sun]#zonecfg -z <zone> delete -F

Example: [sun]#zonecfg -z sunz01 delete -F

using above command you can delete or remove the configuration file of solaris local zone.

Note: You need to shutdown and uninstall the local zone before deleting the configuration files of Sun Solaris local zone.

3. Command for display zone current configuration:

Please find the below command to display the current configuration of local Solaris zones.

[sun]#zonecfg -z <zone> info

Example: [sun]#zonecfg -z sunz01 info

This command output show you the zonename, zonepath, autoboot etc attributes information of the solaris zone.

4. Command for zone creation file:

Please find the below command to create a solaris zone creation file.

[sun]#zonecfg -z <zone> export

Example: [sun]#zonecfg -z sunz0 export

Once the creation file has been export you can use this file to another zone creation as well as for restoration of this local zone if any problem occur on this zone.

How to use zoneadm command in Solaris Servers

When you are working on the Solaris operating system then you must aware about this command "zoneadm" which is basic command in Solaris operating system. In this post I would like to explain you how to use the zoneadm command in Solaris servers.

"zoneadm" command are used for verification, installation, boot or viewing of the local zones which are created on the Solaris Server. Please find the below syntax with an example.

1. Verify a Solaris zone:

To verify the local solaris zone you need to run the below command with syntax.

[sun]#zoneadm -z <zone> verify

Example: [sun]#zoneadm -z sunz01 verify

In this example once you run the above command, if your zone is installed properly without any error then this is not showing you any output, that's means it is verified. After running the command if it is showing a message then you need to check the configuration of this zone.

2. Installing a Solaris zone:

To install the local Solaris zone you need to run the below command with syntax.

[sun]#zoneadm -z <zone> install

Example: [sun]#zoneadm -z sunz01 install

In this example when you run the above command then your local zone has been started for installation. It is installed the local zone using the Solaris repostiory or flar images which you are kept at server location.

3. Ready a Solaris zone:

To move the local zone in ready or maintainance state you need to run the below command.

[sun]#zoneadm -z <zone> ready

Example: [sun]#zoneadm -z sunz01 ready

In this example, when we run the above command then your local zone moved in to ready or maintianance state.

4. Boot a Solaris zone:

To boot the solaris zone on global system, you need to run the below command with syantx.

[sun]#zoneadm -z <zone> boot

Example: [sun]#zoneadm -z sunz01 boot

After running the above command your local solaris zone has been boot successfully if it is not showing any error during boot time. If you see any message during the boot time then please check where is the issue.

5. Reboot a Solaris zone:

To reboot or restart the solaris zone on Solaris server, you need to perform the below command on global zone.

[sun]#zoneadm -z <zone> reboot

Example: [sun]#zoneadm -z sunz01 reboot

Using this command the local zone "sunz01" has been restart again successfully. You need to run this command from global zone only.

6. Shutdown/Halt a Solaris zone:

If you want to shutdown or halt your local zone without login it, then you need to run the below command from global zone.

[sun]#zoneadm -z <zone> halt

Example: [sun]#zoneadm -z sunz01 halt

After running this command local solaris zone state change from running to installed state that's means your server is shutdown now.

7. Uninstall a Solaris zone:

If you want to uninstall any solaris zone then you need to run the below command for uninstall the zone.

[sun]#zoneadm -z <zone> uninstall -F

Example: [sun]#zoneadm -z sunz01 uninstall -F

"-F" syntax is used to uninstall the zone forcefully. 

8. Viewing a Solaris zone:

if you want to local zone current status and any other display information you need to run the below command. 

[sun]#zoneadm list -icv

 ID NAME       STATUS      PATH               BRAND   IP
   0 global         running        /                        solaris      shared
   1 sunz01        running       /zones/sunz01   solaris      excl
   2 sunz02        running       /zones/sunz02   solaris      excl

Using above command you can check the current status of all installed zones on Solaris server. It is show you the zone path and zone information. All the above command you need to run from Global zone with root privileges.

Monday, March 20, 2017

10 Practical Examples of RPM Commands in Linux

In this post, I will explain you the usage of RPM (Red Hat Package Manager) command with an example. RPM commands are widely used in Linux operating system to install, remove or update the packages on operating system.

RPM (Red Hat Package Manager) is a default open source and package management utlity which is widely used on Redhat, CentOS linux operating system. You can install , remove, upgrade the packages using this commnad. In this post We will explain each syntax with an example so you can understand how this command is very useful on linux operating system. So here, we will explain best 20 example which is related to Red Hat Package Manager.

1. How to Check an RPM Signature Package:

This command with syntax is used for to check the PGP signature of packages before installing them on your Linux systems and make sure its integrity and origin is fine.

[root@locahost]# rpm --checksig vsftpd-2.2.2-14.el6.x86_64.rpm
vsftpd-2.2.2-14.el6.x86_64.rpm: rsa sha1 (md5) pgp md5 OK

2. How to Install an RPM Package:

Using below syntax you can install the rpm packages on the linux system.

[root@localhost]# rpm -ivh vsftpd-2.2.2-14.el6.x86_64.rpm
Preparing...               ########################################### [100%]
1:vsftpd                    ########################################### [100%]

On the above syantx we are using "-i" option to install the rpm packages on Linux operating system.

3. How to check dependencies of RPM Package before Installing:

If you want to check which packages or dependency is required for RPM packages then you can run the below command to check the dependency.

[root@localhost]# rpm -qpR samba-winbind-3.6.23-12.el6.x86_64.rpm

Here, you can find the syantx meaning of the above command.
-q : Query a package.
-p : List capabilities this package provides.
-R: List capabilities on which this package depends.

4. How to Install a RPM Package Without Dependencies:

If you want to install the packages without any dependency please use the below syntax.

[root@localhost]# rpm -ivh --nodeps samba-winbind-3.6.23-12.el6.x86_64.rpm
Preparing...                       ########################################### [100%]
1:Samba-winbind             ########################################### [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:

If you want to check which RPM package is installed on the operating system then please use -q option with package name.

[root@localhost]# rpm -q samba
package samba is not installed

If you see the samba packages is not installed on my system so it is show you this message.

[root@localhost]# rpm -q vsftpd
vsftpd-2.2.2-14.el6.x86_64

You can see the above ftp server packages is installed on the system.

6. How to Upgrade a RPM Package:

If you want to upgrade any RPM packages then please use "-U" syntax with rpm name.

[root@localhost]# rpm -Uvh vsftpd-3.0.2-11.el6.x86_64.rpm
Preparing...             ########################################### [100%]
1:vsftpd                 ########################################### [100%]

If you see the above example the packages is upgrade with the new version of vsftpd.

7. How to Remove a RPM Package:

If you want to uninstall or remove the package from the server then please use "-e" erase option is used to remove package.

[root@localhost]# rpm -evv vsftpd

Using above command we can remove the packages with all dependency.

8. How to Remove an RPM Package Without Dependencies:

If you want to remove installed packages without any dependecy then use the below syntax to remove the rpm.

[root@localhost]# rpm -ev --nodeps vsftpd

Using above syntax "--nodeps" we can remove the packages without dependency.

9. How to Import an RPM GPG key:

If you want to import the RPM GPG key then please verify RHEL/CentOS/Fedora packages, you must import the GPG key.

[root@localhost]# rpm --import /etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-6

So using above syantx we can import the GPG key on the server.

10. How to List all Imported RPM GPG keys:

To print all the imported GPG keys in your system, use the following command.

[root@localhost]# rpm -qa gpg-pubkey*
gpg-pubkey-0608b895-4bd22942
gpg-pubkey-7fac5991-4615767f

You can see the above entry these are the GPG key which is installed on the server.

Thursday, March 16, 2017

Step by Step Configuration of NTP Server on HP-UX Server

In this post, I would like to explain how we configure the NTP (network time protocol) server on HP-UX operating system server. In my recent post you can found the NTP configuration on Solaris and AIX platform. 

As you know NTP ( Network time Protocol) is one of the oldest internet protocol still in use and it allows the synchronization of computer clocks distributing UTC (Coordinated Universal Time) over the network. It is basaiclly used for time synchronization on Unix servers.

Step by Step Configuration of NTP Server on HP-UX:

1. In the first step we will check the configuration files of "xntpd" daemon. By default the configuration file for this daemon is "/etc/rc.config.d/netdaemons".

# vi /etc/rc.config.d/netdaemons

######################################
# xntp configuration.  See xntpd(1m) #
######################################
#
#  Time synchronization daemon
#
# NTPDATE_SERVER: name of trusted timeserver to synchronize with at boot
# (default is rootserver for diskess clients)
# XNTPD:        Set to 1 to start xntpd (0 to not run xntpd)
# XNTPD_ARGS:  command line arguments for xntpd
#
# Also, see the /etc/ntp.conf and /etc/ntp.keys file for additional
# configuration.
#
export NTPDATE_SERVER=
export XNTPD=0
export XNTPD_ARGS=

This is default configuration entry of this file so for xntpd daemon we need to change the variable which is defined.

export NTPDATE_SERVER='ntp.in.pool.org'
export XNTPD=1
export XNTPD_ARGS=

Note: You must change the NTPDATE server name.

2. For ntp config please set the correct timezone is setup in /etc/TIMEZONE file.

hpx:/> cat /etc/TIMEZONE
TZ=IST-5:30
export TZ

You can edit the file in vi editor and change the time zone as per your location.

3. Now, we need to make some changes in NTP configuration files. 

hpx29:/> cat /etc/ntp.conf
#Configuration NTP des serveurs
server ntp.in.org.com
server ntpin.in.org.com

You need to replace ntp server name accordingly. In my post I will use dummy server name.

4. After setting the NTP server name we need to restart the NTP service on HP-UX operating system and verify the ntp configuration.

hpx:/> /sbin/init.d/xntpd restart

hpx:/> ntpq -p

If it is showing you correct ntp server information now. You can match these information with the NTP server name which we use in above step.

Tuesday, March 14, 2017

How to configure NTP Server on AIX Operating system

In the last post, I had explained the NTP (Network Time Protocol) on Solaris 10 & 11 server. Now in this post, I will explain the same NTP server and client configuration for AIX operating system.

As you know NTP ( Network time Protocol) is one of the oldest internet protocol still in use and it allows the synchronization of computer clocks distributing UTC (Coordinated Universal Time) over the network.

Step by Step Configuration of NTP:

1. In the initial step we must verify that we have check the available NTP server on AIX server. For this please run the below command.

AIX:/>lssrc -ls xntpd
-----------------------------------------------
 Program name:    /usr/sbin/xntpd
 Version:         3
 Leap indicator:  00 (No leap second today.)
 Sys peer:        ntp.aix.in.com
 Sys stratum:     4
 Sys precision:   -18
 Debug/Tracing:   DISABLED
 Root distance:   0.014709
 Root dispersion: 0.066422
 Reference ID:    192.168.1.22
 Reference time:  dc721077.d3a8e000  Tue, Mar 14 2017  7:47:19.826
 Broadcast delay: 0.003906 (sec)
 Auth delay:      0.000122 (sec)
 System flags:    pll monitor filegen
 System uptime:   19248381 (sec)
 Clock stability: 0.000107 (sec)
 Clock frequency: 0.000000 (sec)
 Peer: ntp.aix.in.com
      flags: (configured)(sys peer)
      stratum:  3, version: 3
      our mode: client, his mode: server
 Peer: ntpuk.aix.in.com
      flags: (configured)(sys peer)
      stratum:  3, version: 3
      our mode: client, his mode: server
Subsystem         Group            PID          Status
xntpd            tcpip            8520514      active
------------------------------------------------------

You can found the above output once you run the above command to check the available NTP server. On my AIX machine if you see the sys peer should show a valid server (ntp.aix.in.com). If the server is not showing any ntp server then we need to correct it by adding a server line into /etc/ntp.conf and will take restart of "xntpd" services.

Note : In this post I will use my dummy NTP name instead of real NTP server because of security reason.

2. As your NTP server is not configured and it is show "insame" then you need to add manual entry on the NTP configuration file.

AIX:/>vi /etc/ntp.conf

server ntp.aix.in.com
server ntpuk.aix.in.com

Once you added these ntp server entry manually on the configuration file then please take a restart of NTP services.

AIX:/>stopsrc -s xntpd
AIX:/>startsrc -s xntpd

Using above command we can stop and start the "xntpd" service on AIX operating system.

3. In this step you need to again verify the status of newly added NTP server.

AIX:/>lssrc -ls xntpd

It is taking some time that time because it synchronize process is running. Once the synchronization has been complete and you run the above command you can found the NTP server entry as describe in Step 1.

Step by Step configuration of NTP Client:

1. On the client machine you need to again verify that you have a server suitable for synchronization or not. For this please run the below command.

AIX:/>ntpdate -d ntp.aix.in.com
-----------------------------------------------------------
14 Mar 08:16:21 ntpdate[64356890]: 3.4y
transmit(192.168.1.22)
receive(192.168.1.22)
transmit(192.168.1.22)
receive(192.168.1.22)
transmit(192.168.1.22)
transmit(192.168.1.22)
transmit(192.168.1.22)
server 192.168.1.22, port 123
stratum 16, precision -6, leap 11, trust 000
refid [63.15.23.11], delay 0.03688, dispersion 24.00334
transmitted 4, in filter 4
reference time:      00000000.00000000  Thu, Feb  7 2036  7:28:16.000
originate timestamp: dc721745.3ff1b000  Tue, Mar 14 2017  8:16:21.249
transmit timestamp:  dc721746.3d08a000  Tue, Mar 14 2017  8:16:22.238
filter delay:  0.03688  0.05624  0.00000  0.00000
               0.00000  0.00000  0.00000  0.00000
filter offset: -0.00081 -0.00750 0.000000 0.000000
               0.000000 0.000000 0.000000 0.000000
delay 0.03688, dispersion 24.00334
offset -0.000812

14 Mar 08:16:23 ntpdate[64356890]: no server suitable for synchronization found
--------------------------------------------------------------------------

If you get the message ," no server suitable for synchronization found", verify xntpd is running on the server also verify that no firewalls are blocking port 123.

2. If the no server suitable for synchronization then you must specify the xntpd server in /etc/ntp.conf.

AIX:/>vi /etc/ntp.conf

server ntp.aix.in.com

Once you added the NTP server entry on client configuration file then restart the "xntpd" service again.

AIX:/>startsrc -s xntpd

3. If you want to start the xntpd service on boot time then you need to uncomment the below lines on the configuration file.

AIX:/>vi /etc/rc.tcpip

Unconmment the following line

start /usr/sbin/xntpd "$src-running"

4. Now verify the NTP server on client machine has been synchronized or not. Please use the same command which we used for checking the status.

AIX:/>lssrsc -ls xntpd

This time on the NTP client machine sys peer should display the IP Address or name of your "xntpd" server. As you know it is taking some time to synchronization so you must wait for time.

How to disable the SELinux in Linux machine

In this post, I will explain you the how to disable SELINUX on Redhat or CentOS Operating system. Before going to main work first we need to understand what is SELINUX and how its work on Linux enviorement.

Security-enhanced Linux (SELINUX): SELinux is know as Security enhanced linux system which is the security feature of the Linux kernel system. It is define the security Policy which makes system proctative agaginst the misconfiguration of the daemons. SELinux running in 3 modes which is disabled, enabled and permissive. We will explain these mode in configuration steps.

How to disable SELinux on Linux system:

1. In the first step you can check the current status of SELinux. To do this please run the below command.

[redhat]# getenforce
Enabled

"getenforce" command is used for checking the current status of SELinux.

2. As you see on my machine when I run the above command my SElinux is enabled, So in this step we will change the SELinux mode.

[redhat]# vi /etc/sysconfig/selinux

# This file controls the state of SELinux on the system.
# SELINUX= can take one of these three values:
#     enforcing - SELinux security policy is enforced.
#     permissive - SELinux prints warnings instead of enforcing.
#     disabled - No SELinux policy is loaded.
SELINUX=disabled
# SELINUXTYPE= can take one of these two values:
#     targeted - Targeted processes are protected,
#     mls - Multi Level Security protection.
SELINUXTYPE=targeted

Normally selinux configuration file you can found on the above location. You can edit the SELINUX entry to disabled. All the command is run by super user "root" only.

3. Once you change the entry in SELinux configuration file then for permanent effect you need to take a reboot of the system.

[redhat]#init 6

Once you reboot the server all the configuration files changes has been done.

4. In the last step you will run the "getenforce" command again to verify the new status of SELinux.
[redhat]# getenforce
Disabled

If you comparison the both step 1 and this step output you can found that SELinux policy is not disabled on the Linux operating system.

Friday, March 10, 2017

How to mount CIFS file system on Linux Server

Hope you are doing well at your end. In this post, I will explain how we mount the CIFS file system on Linux operating system.

Normally on linux machine if we mount the any other linux machine folder is quite easiy in comparision to mount the window shared folder on linux machine. So let's going to final topic where i will explain step by step method to mount the CFS folder on Linux server.

Step by Step method for Mount CIFS on Linux Server:

1. In the initial step we will gather all rpm's or packages information which is required for CIFS file system.

redhat# rpm -qa | grep cifs 
cifs-utils-4.8.1-20.el6.x86_64

if you see the above output, this packages is required for CIFS file system on Linux system. So you can install this rpm using rpm command if you have rpm packages on the server otherwise you will install the packages using YUM utility.

redhat#rpm -ivh cifs-utils-4.8.1-20.el6.x86_64.rpm

if you are using YUM, then please install the packages using below command.

redhat#yum install cifs-utils*

it is installed all required dependency related to CIFS file system.

2. In this step, we will create the mount point on the server where we need to mount the CIFS file system.

redhat# mkdir -p /backup/cifs

We will create the above mount directory where i will mount the file system.

3. Now, we will create a CIFS user and assign a password so the user can access mount folder.

redhat# touch /etc/cifspasswd
redhat# chmod 600 /etc/cifspasswd

redhat#vi /etc/cifspasswd

user=castwebsvc
password=*******

4. In this step we need to make a permanent entry of mounted file system so once we reboot the machine mounted file system not umount.

redhat# vi /etc/fstab

ADD fstab entry :

//WindowsServer/share /mount/point cifs rw,mand,user=USER,password=PASS 0 0

Example :
//192.168.0.1/CAST_data4/AICCodeUpload  /backup/cifs cifs   rw,mand,credentials=/etc/cifspasswd         0 0

You can take an example for your system. Please change the mount point as per your requirement.

5. In the final step you need to mount the file system using below command.

redhat# mount /backup/cifs
redhat# mount -a

Using above command the CIFS file system has been mounted successfully.