.::: Install/Upgrade Minimal to Desktop Environment on Centos/RHEL(Redhat Enterprise Linux ) :::.

1. List Installed and Available Groups
[root@TeguhLab ~]# yum grouplist
Loaded plugins: fastestmirror
There is no installed groups file.
Maybe run: yum groups mark convert (see man yum)
Loading mirror speeds from cached hostfile
 * base: sumberterbuka.beritagar.id
 * extras: sumberterbuka.beritagar.id
 * updates: sumberterbuka.beritagar.id
Available environment groups:
   Minimal Install
   Compute Node
   Infrastructure Server
   File and Print Server
   Basic Web Server
   Virtualization Host
   Server with GUI
   GNOME Desktop
   KDE Plasma Workspaces
   Development and Creative Workstation

.::: How To Enable SNMP & SNMPTrap on Alcatel Lucent/Nokia Router(7750, 7710, 7705,7750) :::.

A. Enable SNMP Router Alcatel Lucent

1. Check snmpwalk router

# snmpwalk -v2c -c teguht 10.10.10.10 sysDescr

# snmpwalk -v2c -c teguht 10.10.10.10 1.3.6.1.2.1.1

[root@TeguhLab ~]# snmpwalk -v2c -c teguht 10.10.10.10 sysDescr

Timeout: No Response from 10.10.10.10

[root@TeguhLab ~]# snmpwalk -v2c -c teguht 10.10.10.10 1.3.6.1.2.1.1

Timeout: No Response from 10.10.10.10

[root@TeguhLab ~]#

.::: How To Commission & Enable SNMP an OmniSwitch Alcatel Lucent for NMS :::.

Before you begin. See the appropriate OmniSwitch documentation for more information about the CLI command syntax and SNMP.

Note: The NMS cannot discover an OmniSwitch that is configured with the factory default settings.

Note: You must use a direct console port connection to access an OmniSwitch for the first time. All other management methods such as SNMP, Telnet, FTP, and HTTP, are disabled until you enable them.

1. Open a console window using a direct console port connection to the OmniSwitch.

2. Create a Loopback0 interface and assign an IP address to the interface by entering

the following:

ip interface Loopback0 address xxx.xxx.xxx.xxx

where

xxx.xxx.xxx.xxx is the IP address of the interface

.::: How to Check License subscription-manager RHEL(Red Hat Enterprise Linux) :::.

Red Hat Enterprise Linux Server subscription is available at no cost for development purposes. Developers need to register for the Red Hat Developer Program and agree to licensing terms forbidding production use. This free developer subscription was announced on March 31, 2016.

There are also "Academic" editions of the Desktop and Server variants. They are offered to schools and students, are less expensive, and are provided with Red Hat technical support as an optional extra. Web support based on number of customer contacts can be purchased separately.

1. Sample command
# subscription-manager orgs
# subscription-manager refresh
# subscription-manager status
# subscription-manager list
# subscription-manager list --consume

.::: How To Upgrade Cacti on Linux :::.

note: this cace, upgrade cacti 0.8.8.b to 0.8.8.h
1. Backup the old Cacti database
mysqldump -l --add-drop-table <db_name> -u <user> -p  > mysql.cacti
[root@TeguhLab data]# mysqldump -l --add-drop-table cacti -u root -p > mysql.cacti
Enter password:
[root@TeguhLab data]# ls
mysql.cacti  rpmforge-release-0.5.3-1.el6.rf.x86_64.rpm
[root@TeguhLab data]# ls -lh
total 156K
-rw-r--r-- 1 root root 138K Aug  3 14:45 mysql.cacti
-rw-r--r-- 1 root root  13K Mar 20  2013 rpmforge-release-0.5.3-1.el6.rf.x86_64.rpm
[root@TeguhLab data]#

.::: How To Install Cacti On Linux :::.

Cacti is a complete frontend to RRDTool, it stores all of the necessary information to create graphs and populate them with data in a MySQL database. The frontend is completely PHP driven. Along with being able to maintain Graphs, Data Sources, and Round Robin Archives in a database, cacti handles the data gathering. There is also SNMP support for those used to creating traffic graphs with MRTG.

Note : using mysql 5.1.73 & cacti 0.8.8.b

1. Disable SE Linux
[root@TeguhLab ~]# cat /etc/selinux/config

# 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

.::: Different Output OID ifDescr & ifAlias :::.

1. Different ifDescr, ifName & ifAlias
ifDescr OBJECT-TYPE
    SYNTAX      DisplayString (SIZE (0..255))
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
            "A textual string containing information about the
            interface.  This string should include the name of the
            manufacturer, the product name and the version of the
            interface hardware/software."
    ::= { ifEntry 2 }

.::: Sample output snmpwalk OID on MIB IF-MIB :::.

1. Definition IF-MIB
The MIB module to describe generic objects for network interface sub-layers. This MIB is an updated version of MIB-II's ifTable, and incorporates the extensions defined in RFC 1229.

2. OID on IF-MIB include calculate
ifTable
1.3.6.1.2.1.2                            interfaces                                           NODE
1.3.6.1.2.1.2.1                          ifNumber                                             LEAF  Integer32
1.3.6.1.2.1.2.2                          ifTable                                              NODE
1.3.6.1.2.1.2.2.1                        ifEntry                                              NODE
1.3.6.1.2.1.2.2.1.1                      ifIndex                                              LEAF  InterfaceIndex
1.3.6.1.2.1.2.2.1.2                      ifDescr                                              LEAF  DisplayString
1.3.6.1.2.1.2.2.1.3                      ifType                                               LEAF  IANAifType
1.3.6.1.2.1.2.2.1.4                      ifMtu                                                LEAF  Integer32
1.3.6.1.2.1.2.2.1.5                      ifSpeed                                              LEAF  Gauge32

.::: How To Export Display on Linux/Unix Platform (Installer User Interface Mode Not Supported):::.

1. example running java on linux using CLI
[root@TeguhLab /]# su oracle
bash-4.1$ cd /
bash-4.1$ ./teguh.bin
Preparing to install...
Extracting the JRE from the installer archive...
Unpacking the JRE...
Extracting the installation resources from the installer archive...
Configuring the installer for this system's environment...

Launching installer...

Graphical installers are not supported by the VM. The console mode will be used instead...

Preparing CONSOLE Mode Installation...

.::: How to display login banner before & After login(Prelogin, Postlogin) On Unix/Linux :::.

Pre login banner is use for sending a warning message before authentication may be relevant for getting legal protection or just give out information to users. The contents of the specified file are sent to the remote user before authentication is allowed. This option is only available for protocol version 2. By default, no banner is displayed (if you are using latest version of Linux/UNIX then you do not have to worry about version issue)

A. Display SSH Warning Message to Users Before Login

1) By default sshd server turns off this feature.

.::: Enable Crontab on Linux/Unix Platform :::.

Crontab  is  the program used to install, remove or list the tables used to drive the cron(8) daemon.  Each user can have their own crontab, and though these are files in /var/spool/ , they are not intended to be edited directly. For SELinux in mls mode can be even more crontabs - for  each  range.  For  more  see selinux(8).

The  cron jobs could be allow or disallow for different users. For classical crontab there exists cron.allow and cron.deny files.  If cron.allow file exists, then you must be listed therein in order to be allowed to use this command.  If the cron.allow file does not exist but the cron.deny file  does  exist,  then you must not be listed in the cron.deny file in order to use this command.  If neither of these files exists, only the super user will be allowed to use this command.  The second option is using PAM authentication, where you set up users, which could  or  couldn’t  use  crontab  and  also  system  cron  jobs  from /etc/cron.d/.

::: How to Upgrade RHEL/Redhat Enterprise Linux 7 Using Repolocal, ISO & Online :::.

1. capture release version before upgrade
[root@teguhlab yum.repos.d]# cat /etc/redhat-release
Red Hat Enterprise Linux Server release 7.2 (Maipo)
[root@teguhlab yum.repos.d]#

2. Mounting Image Rhel 7.3/Latest Using ISO File or DVD Room/Repolocal
detail on http://teguhth.blogspot.co.id/2017/07/how-settting-install-package-os-redhat.html

3. Clean all
# yum clean all
# subscription-manager clean
All local data removed

.::: How Settting & Install Package OS Redhat Enterprise Linux(Rhel) 7 Using Repolocal, ISO File & rpm file :::.

A. Using Repolocal(DVD)
1. Make sure DVD mounting
[root@teguhlab yum.repos.d]# df -kh
Filesystem      Size  Used Avail Use% Mounted on
/dev/sda3       261G  3.0G  258G   2% /
devtmpfs        9.8G     0  9.8G   0% /dev
tmpfs           9.8G   84K  9.8G   1% /dev/shm
tmpfs           9.8G  9.0M  9.8G   1% /run
tmpfs           9.8G     0  9.8G   0% /sys/fs/cgroup
/dev/sda1       187M  146M   42M  78% /boot
tmpfs           2.0G   20K  2.0G   1% /run/user/0
/dev/sr0        3.6G  3.6G     0 100% /run/media/root/RHEL-7.3 Server.x86_64
[root@teguhlab yum.repos.d]#