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Enhancing the Scala Twitter library for Java Clients

Make it substantially easier to access Twitter than just opening an HTTP connection and doing the work by hand as well as making Twitter easily accessible to Java clients and Java developers. With this new Scala Scitter library you wont have too much to do to get started leveraging  the Twitter API.
 

Configuring iSCSI initiator on Red Hat Linux 4 and 5


I was configuring iSCSI initiator in one of our Red Hat Linux 4 server, couple of weeks ago, after a day's work at last I became successful. Ohhh thank GOD. Last week again I have asked to configure iSCSI on Red Hat Linux 5 server I was cool, I already did this on RHEL 4, but after installing the package on RHEL 5 and looking at configuration file takes my breath away, a completely new configuration file not even able to compare with RHEL4. Ohhhh GOD help me. Again after a days work I was successful sharing my work with you guys it may helpful to you.

Configuring iSCSI initiator in Red Hat Enterprise Server 4

iSCSI (Internet Small Computer System Interface)

Concepts

Initiator

An initiator functions as an iSCSI client. An initiator typically serves the same purpose to a computer as a SCSI bus adapter would, except that instead of physically cabling SCSI devices (like hard drives and tape changers), an iSCSI initiator sends SCSI commands over an IP network. An initiator falls into two broad types:

Software initiator

A software initiator uses code to implement iSCSI. Typically, this happens in a kernel-resident device driver that uses the existing network card (NIC) and network stack to emulate SCSI devices for a computer by speaking the iSCSI protocol. Software initiators are available for most mainstream operating systems, and this type is the most common mode of deploying iSCSI on computers.

Hardware initiator

A hardware initiator uses dedicated hardware, typically in combination with software (firmware) running on that hardware, to implement iSCSI. A hardware initiator mitigates the overhead of iSCSI and TCP processing and Ethernet interrupts, and therefore may improve the performance of servers that use iSCSI.

Target

iSCSI refers to a storage resource located on an iSCSI server (more generally, one of potentially many instances of iSCSI running on that server) as a "target". An iSCSI target usually represents hard disk storage. As with initiators, software to provide an iSCSI target is available for most mainstream operating systems.
Common deployment scenarios for an iSCSI target include:

Storage array

In a data center or enterprise environment, an iSCSI target often resides in a large storage array, such as a NetApp filer or an EMC Corporation NS-series computer appliance. A storage array usually provides distinct iSCSI targets for numerous clients.[1]

Software target

In a smaller or more specialized setting, mainstream server operating systems (like Linux, Solaris or Windows Server 2008) and some specific-purpose operating systems (like NexentaStor, StarWind iSCSI Target, FreeNAS, iStorage Server, OpenFiler or FreeSiOS) can provide iSCSI target's functionality.

Addressing

Special names refer to both iSCSI initiators and targets. iSCSI provides three name-formats:

iSCSI Qualified Name (IQN)
Format: iqn.yyyy-mm.{reversed domain name} (e.g. iqn.2001-04.com.acme:storage.tape.sys1.xyz) (Note: there is an optional colon with arbitrary text afterwards. This text is there to help better organize or label resources.)

Extended Unique Identifier (EUI)

Format: eui.{EUI-64 bit address} (e.g. eui.02004567A425678D)
T11 Network Address Authority (NAA)
Format: naa.{NAA 64 or 128 bit identifier} (e.g. naa.52004567BA64678D)
IQN format addresses occur most commonly. They are qualified by a date (yyyy-mm) because domain names can expire or be acquired by another entity.

Installation on Red Hat Linux 4

# rpm -ivh iscsi-initiator-utils-4.0.3.0-7.i386.rpm

IQN no of Red Hat Linux 4 Server (/etc/initiatorname.iscsi file)

Each iSCSI device on the network, be it initiator or target, has a unique iSCSI node name. Red Hat uses the iSCSI Qualified Name (IQN) format with the initiator that ships with Red Hat Enterprise Linux. In the IQN format, a node name consists of a predefined section, chosen based on the initiator manufacturer, and a unique device name section which is editable by the administrator.
Provide this IQN number to your IPSAN Administrator he will create and assign LUN to this IQN

Configuration ( /etc/iscsi.conf)

Terms

To globally configure a CHAP username and password for initiator
authentication by the target(s), uncomment the following lines:

Outgoingusername is something we create at Target to authenticate the LUN assigned to this

OutgoingUsername=
OutgoingPassword=


To globally configure a CHAP username and password for target(s)
authentication by the initiator, uncomment the following lines:

IncomingUsername=
IncomingPassword=


Settings in config file ( /etc/iscsi.conf)

DiscoveryAddress=ipaddress or hostname of your IPSAN
OutgoingUsername=username created in targetserver for accssing this LUN
OutgoingPassword= password created in targetserver for accssing this LUN
LoginTimeout=15

Installation on Red Hat Linux 5

# rpm -ivh iscsi-initiator-utils-6.2.0.868-0.18.el5.i386.rpm

IQN no of Red Hat Linux 5 Server (/etc/iscsi/initiatorname.iscsi)

Configuration ( /etc/iscsi/iscsid.conf)

Settings

# To enable CHAP authentication set node.session.auth.authmethod
# to CHAP. The default is None.
node.session.auth.authmethod = CHAP

# To set a CHAP username and password for initiator
# authentication by the target(s), uncomment the following lines:
node.session.auth.username = testuser
node.session.auth.password = testpassword


# To enable CHAP authentication for a discovery session to the target
# set discovery.sendtargets.auth.authmethod to CHAP. The default is None.
discovery.sendtargets.auth.authmethod = CHAP

# To set a discovery session CHAP username and password for the initiator
# authentication by the target(s), uncomment the following lines:
discovery.sendtargets.auth.username = testuser
discovery.sendtargets.auth.password = testpassword

#service iscsi restart

Will get the output like this

Stopping iSCSI daemon:
iscsid dead but pid file exists [ OK ]
Turning off network shutdown. Starting iSCSI daemon: [ OK ]
[ OK ]
Setting up iSCSI targets: iscsiadm: No records found!
[ OK ]

Now discover the targets.

#iscsiadm -m discovery -t sendtargets -p 192.168.x.x ( IP address of Target)

# service iscsi restart

Will get like this
Logging out of session [sid: 1, target: iqn.1991-05.com.microsoft:aio1200-oracle-rac-target, portal: 192.168.x.x,3260]
Logout of [sid: 1, target: iqn.1991-05.com.microsoft:aio1200-oracle-rac-target, portal: 192.168.x.x,3260]: successful
Stopping iSCSI daemon:
iscsid dead but pid file exists [ OK ]
Turning off network shutdown. Starting iSCSI daemon: [ OK ]
[ OK ]
Setting up iSCSI targets: Logging in to [iface: default, target: iqn.1991-05.com.microsoft:aio1200-oracle-rac-target, portal: 192.168.251.10,3260]
Logging in to [iface: default, target: iqn.1991-05.com.microsoft:aio1200-oracle-rac-target, portal: 192.168.x.x,3260]


Important.

If you made any changes to the configuration file first remove the iqn from cache using this command

#iscsiadm -m node -T iqn.1991-05.com.microsoft:aio1200-oracle-rac-target -o delete

After issuing this command restart the iscsi to take effect the configuration you changed

#Service iscsi restart

After restarting the service discover again using

#iscsiadm -m discovery -t sendtargets -p 192.168.x.x (IP address of Target)

 

NEWB's adventure's in Linux From Scratch

 Hello,

    Well, I 've installed grub on a hard disk, compiled a few kernels. I feel like I'm learning but not at the clip I 'd like. It's been approximately 30 odd days and I've tried a few distro's . One thing is for sure, I understand that "sudo" is a great way to improve the security on your system. However, having it installed on the machine I'm compiling programs on has been annoying. Just so you understand I've been building in a terminal on my Crunchbang linux box and sudo this sudo that is annoying.  I'm sure that there's a way around this , maybe makeing a dir with me as the group and usr, then going into that directory and changing to the user then running the programs, I don't know guess I'll have to try something.

   I  continuing progress on my Linux user's guide reading. Having a difficult time with Shell Scripting. I've only got a couple of chapters, but I see already it 's a very important part of admin on linux machines. I also notice another program called Python that' s similar they say. Curious about that one. I'm sure I'll be posting about bash scripts on the Forums. Hope to meet you there.

 

gnome shell group

 

 Created a new group today called gnome shell for discussion tips and tricks and the rest for those of us who are using gnome shell right now. Nothing like getting a jump!

 

Practical Exercise Tips For Busy Linux Geeks

God invented USB sticks to help us improve our health. Network file transfers are like plastering bacon grease to your arteries. Using the good old-fashioned Sneakernet protocol adds more tens of feet of healthy walking to your day.
 

Intel "Atom" media server?

Hello again,

Recently, I've been doing alot of thinking about cost.  I have a ton of media files. and I want to share them across my home network (gigabit ethernet,wired).

  The economy the way it is , I believe it smart to look at all parts of the equation. I 'm no engineer,but electricity is part of the cost. I would think there should be substantial savings here? I'd like to hear what you have to say.

 Considering the , intel board ,msi wind, or the supermicro server board.

 

Zenoss Releases New Version of its Enterprise IT Monitoring Product; Guarantees 50% Cost Savings Over Traditional Solutions

 

Annapolis, MD - June 2, 2009 - Zenoss Inc., the fastest-growing alternative to the "Big 4" for enterprise network and systems monitoring, today released a new version of its award-winning software, Zenoss Enterprise. The new product release dramatically eases the burden of managing and administering enterprise IT monitoring, providing companies with one product to discover, monitor, alert, and report. The company is backing Zenoss Enterprise implementations with an industry-first guarantee of 50% or more cost savings on licensing, maintenance, and deployment compared to traditional products from HP, IBM, CA, and BMC.*

 

"Zenoss' customer base continues to grow as HP, IBM, CA and BMC customers say enough is enough," said Bill Karpovich, co-founder and CEO of Zenoss. "Companies are no longer willing to let their IT monitoring requirements be held hostage by vendors imposing exorbitant costs, too much complexity, and multi-product requirements. This marks a new day in enterprise IT monitoring - customers get the functionality, support, and flexibility they demand at a price that makes sense."

 

"Zenoss Enterprise excels in meeting D & E Communication's IT monitoring needs," said Troy Wingenroth, VP of IT, D & E Communications. "We have significantly reduced our costs and streamlined our monitoring operations with Zenoss' one product to discover, monitor, alert, and report." 

 

The latest version adds several features and enhancements that align with needs of enterprise IT infrastructure monitoring. New features include:

 

  • l Normalization of Metrics Across Heterogeneous Technologies -A single, consistent view of monitoring information across Linux, Unix and Microsoft Windows platforms that simplifies cross-platform management and enterprise reporting.
  • l Scalable Secure, Monitoring of Linux/Unix Servers- Easy to deploy, agent-less monitoring for Linux and Unix that doesn't compromise scalability or security
  • l Monitoring of Internal or External Web Services-A simple GUI-based configuration able to monitor any cloud-based service
  • l VMware vSphere 4 Support- Extended management capabilities for virtualization management, including support for vSphere 4 and the new vCenter Server
  • l Expanded Device and Applications Support-Turnkey plug-ins for more than 20 new target technologies include Linux, AIX, Nokia Firewalls and Barracuda Anti-Spam appliances;Zenoss monitors over 100 technologies directly out of the box
  • l Simplified Setup and Configuration- Point and click install and configuration wizard guide that greatly reduces setup time and simplifies configuration tasks

 

Zenoss is able to back its savings guarantee by eliminating up-front licensing costs and reducing the time and effort required to deploy and maintain the software.  Zenoss customers benefit from lower costs and can more quickly respond to the needs of their customers and end users.

 

For more information concerning Zenoss Enterprise and the cost savings guarantee, please go to http://www.zenoss.com/.

 

About Zenoss

 

Zenoss is the fastest-growing alternative to the Big 4 for enterprise network and systems monitoring. The company backs Zenoss Enterprise implementations with a 50% or more cost savings guarantee on licensing, maintenance, and deployment compared to traditional products from HP, IBM, CA, and BMC.  Hundreds of enterprises rely on Zenoss software to dramatically ease the burden of managing and administering enterprise IT monitoring, providing companies with one product to discover, monitor, alert, and report. To learn more about Zenoss' award-winning enterprise open source network monitoring software, visit http://www.zenoss.com/.

 

 

*For more information concerning cost-savings guarantee qualifications and pricing assumptions, please see www.zenoss.com.

 

 

Bluenog Launches Higher Education Initiative

 

Company to Offer Integrated Content Management, Portal and Business Intelligence Solutions with Commercial and Open Source Support to Education Sector

PISCATAWAY, N.J. and GETTYSBURG, Penn., June 2, 2009 - Bluenog, an enterprise software and solutions company, announced today it will deliver offerings specifically designed to meet the unique needs of the higher education sector. The announcement was made at the annual Portal 2009 conference at Gettysburg College in Gettysburg, Penn.

The company will extend Bluenog ICETM, its integrated suite of content management, portal development and business intelligence software, to interface with key educational support systems such as Sungard Banner, Resource25, Sakai, Moodle and Blackboard. In addition, the company's professional services division, Bluenog Solutions Group, will offer consulting services designed to help colleges and universities integrate commercial and open source solutions to meet their needs in a cost-effective manner.  

"Colleges and universities are increasingly turning to commercial solutions built on open source projects, such as Bluenog ICE, to address their needs," said Jonathan B. Spira, chief analyst, Basex, a leading knowledge economy research firm. "Having access to professional support, customization, product updates, training and the ability to integrate with existing infrastructure is key for institutions that need to keep costs low without sacrificing functionality."

This initiative follows fresh on the heels of three client implementations at Wellesley College, Columbia University's Center for International Earth Science Information Network (CIESIN) and NYU Langone Medical Center. Bluenog recognized higher education's heightened demand for rich portal development, dynamic website content management and enterprise reporting. Integration with strategic educational and administrative support systems was also a key requirement.

"We are focusing on the higher education sector because collaboration and integration is so important to this space," said Suresh Kuppusamy, CEO and co-founder, Bluenog.  "Having thousands of users on a given portal, these organizations are looking for a way to seamlessly enhance and customize their existing infrastructures at a reasonable cost and Bluenog ICE offers that solution."

Early results from the Bluenog implementation at NYU Langone Medical Center have shown significant savings on up-front licensing and maintenance costs.

Bluenog's ability to integrate with CIESIN's existing applications eliminated the need to migrate any existing content.  CIESIN also benefited from the flexibility of a pre-built portal and BI framework that can be easily added into the overall solution in the future, without any need for custom integration.

Wellesley chose Bluenog ICE after an extensive evaluation of commercial and open source software and related services to revamp their Web presence and boost functionality to provide a richer and more consistent experience for prospective and current students.

About Bluenog

Bluenog is an enterprise software and solutions company.  Our flagship product, Bluenog ICE, is an Integrated Collaborative Environment of content management, portal, and business intelligence software. It eliminates application silos, reduces total cost of ownership and accelerates application development. Leading organizations rely on Bluenog ICE,  a commercial solution built on open source CMS, open source portal and open source BI projects, to build and deploy Rich Internet Applications (RIA) and manage dynamic website content at a fraction of the cost of traditional alternatives. Bluenog Solutions Group meets our customers' unique challenges by combining commercial and open source software into pragmatic solutions.  Headquartered in Piscataway, N.J., Bluenog is also a Red Hat, Oracle and Actuate partner. For more information, visit http://www.bluenog.com/.

# # #

Bluenog ICE is a trademark of Bluenog. All other trade names are the property of their respective owners.

This release, and additional Bluenog resources, is available online in the Feintuch Communications media room at http://www.feintuchcommunications.com/.

 

 

Making My own Desktop Manager: The Design

So I've been looking into Clutter this week and figuring out if (i) it's the right technology to use and (ii) how to incorperate it into the original design, so I have nothing flashy to show in this article (although yesterday I did manage to get xlib composite screenshots into Clutter as actors!), so I'd thought I'd share some more of my design with you instead...

So the main design is very simple, similar to the design of a web site (navbar, content, and side-panel)

Read more... Comment (0)
 

The most important modern innovations of Linux is its transformation into a hypervisor

The battleground has shifted from the Operating System to the hypervisor, and Linux has a clear role to play. One of the most important modern innovations of Linux is its transformation into a hypervisor. Learn how KVM and Lguest paly an important role in this trend.

 

 

Unexpected Things Sometimes Work: What Language is Linux Written in?

I have posted an article on Bright Hub two days ago, which was titled "What Language is Linux Written in." I have discussed the various parts of Linux, from the kernel and device drivers to user programs and I just want to hear the community's critics about it. What else do you have in mind? Anything I forgot to put in? Shoot it in the comments.
 
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