Thursday, June 11, 2015

Barracuda Firewall

Barracuda Firewall

Protect your business from threats, regulate network traffic and keep your critical applications running … without sacrificing network performance.
Find out how by watching the video

Many Threats, One Solution

With the ever growing use of mobile devices, social networks, cloud-based applications and intrusions, securing your business’ vital assets is critical. Besides deliberate outside attacks, your own employees may unwittingly threaten your network by opening email-borne viruses, running bandwidth-hungry applications or accessing the wrong websites.
We offer two next-generation firewalls, the Barracuda Firewall (for SMBs) and the Barracuda NG Firewall (for distributed enterprises). Barracuda firewalls products offer the fastest, most comprehensive and cost-effective solution to keeping your business safe and keeping your mission critical applications running.
Barracuda firewalls protect your digital assets against intrusions, malware, DoS attacks and advanced persistent threats, as well as enforce network access controls and regulate web traffic with integrated application awareness. You will also benefit with granular control to monitor and govern every user, application and URL accessed in your business.

Diagram

Offload resource-intensive content
security to the cloud


Security for the Cloud Era

Barracuda next generation firewalls are designed for the cloud era by automatically offloading resource-intensive tasks such virus and spyware scanning, content filtering and reporting to the cloud so that network performance is not compromised. The cloud-based Web Security Service provides real-time updates to ensure continuous protection against the latest threats. The entire system can be easily managed through a cloud-based interface.
Meanwhile, the on-premises appliance handles bandwidth-sensitive tasks like packet forwarding and routing, Layer 6 application control, Intrusion Protection (IPS), DNS/DHCP services and VPN connectivity for secured access to your network resources – anytime, from anywhere.

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RAID Levels and SQL Server

RAID Levels and SQL Server

SQL Server 2008 R2
20 out of 27 rated this helpful - Rate this topic
RAID (redundant array of independent disks) levels 0, 1, and 5 are typically implemented with SQL Server.

Level 0

This level is also known as disk striping because it uses a disk file system called a stripe set. Data is divided into blocks and spread in a fixed order among all disks in an array. RAID 0 improves read and write performance by spreading operations across multiple disks. Operations can then be performed independently and at the same time.
RAID 0 is similar to RAID 5, but RAID 5 also provides fault tolerance.
Disk striping across 4 disks using RAID 0

Level 1

This level is also known as disk mirroring because it uses a disk file system called a mirror set. Disk mirroring provides a redundant, identical copy of a selected disk. All data written to the primary disk is written to the mirror disk. RAID 1 provides fault tolerance and generally improves read performance but may degrade write performance.
Disk mirroring using RAID 1

Level 2

This level adds redundancy by using an error correction method that spreads parity across all disks. RAID 2 also uses a disk-striping strategy that divides a file into bytes and spreads it across multiple disks. This strategy offers only marginal improvement in disk use and read-and-write performance over mirroring (RAID 1). RAID 2 is not as efficient as other RAID levels and is not generally used.

Level 3

This level uses the same striping method as RAID 2, but the error correction method requires only one disk for parity data. The amount of disk space used varies with the number of data disks. RAID 3 provides some read-and-write performance improvement.

Level 4

This level uses striped data in much larger blocks or segments than RAID 2 or RAID 3. Like RAID 3, the error correction method requires only one disk for parity data. This feature keeps user data separate from error-correction data. RAID 4 is not as efficient as other RAID levels and is not generally used.

Level 5

Also known as striping with parity, this level is the most popular strategy for new designs. RAID 5 is similar to RAID 4, because this level stripes the data in large blocks across the disks in an array. However, RAID 5 differs because it writes the parity across all the disks. Data redundancy is provided by the parity information. The data and parity information are arranged on the disk array so that the two types of information are always on different disks. Striping with parity offers better performance than disk mirroring (RAID 1). However, when a stripe member is missing, read performance is decreased, for example, when a disk fails.
Disk striping with parity using RAID 5

Level 10 (1+0)

This level is also known as mirroring with striping. RAID 10 uses a striped array of disks that are then mirrored to another identical set of striped disks. For example, a striped array can be created by using five disks. The striped array of disks is then mirrored using another set of five striped disks. RAID 10 provides the performance benefits of disk striping with the disk redundancy of mirroring. RAID 10 provides the highest read-and-write performance of any one of the other RAID levels, but at the expense of using two times as many disks.
RAID levels higher than 10 (1 + 0) may offer additional fault tolerance or performance enhancements. These levels generally are proprietary systems. For more information about these types of RAID systems, contact the hardware vendor.
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Community Additions

ADD

Even hardware vendors get it wrong

Cant tell you how many times I tried to purchase RAID 0+1  controllers only to find out it was actually a RAID 1+0. Now it seems MS can't get it right.
m4a2t0t
4/23/2015

RAID10 totally incorrect

RAID10 consists of mirrorsets that are then striped
ConnollyG
5/14/2014

So how did it went?

OK so how did it went?
Paul-Sebastian Manole
3/19/2014

Incorrect RAID 10 Description

The description of RAID 10 (1+0) in this article is incorrect. Raid 1+0 is sets of mirrored disks that are striped together, not sets of striped disks that are mirrored together (that would be RAID 0+1 instead of 1+0, sometimes also called RAID 10).


Just think of the order you have to perform the array configuration in: for 1+0, you mirror (RAID 1) the disks together, then span (RAID 0) across the RAID 1 arrays. 0+1 has you spanning (RAID 0) the sets of disks first, then mirroring (RAID 1) them together.
Thomas Lee
11/20/2011

SQL SERVER




The
timing of this article is both funny, and informative. I am literally
in the process right now of finishing up the design of a new database
for my company. We went with similar hardware to a previously
configuration of theirs (Dell PowerEdge R710). I beefed it out to spec
on the 6-drive bay version (wasn't bad given that there wasn't suppose
to be a budget for this project). I loaded it with 6-146gb drives, RAID
5 with a 12mb cache controller, and 8gb of RAM (wanted to start with
16, but cut it back due to going with only the 6-bay drive config).


Now
- I had not even heard of this kind of venomous talk about RAID 5 and
Databases before. My background has been in I.T. for over 10 years, and
RAID 5 was always a very popular and steady platform, for the most
part. I'm only newly born to SQL Server (since about 2004 as more of an
application analyst), and this is my first titled role as a DBA, but I
have to tell you - I would not have gone above RAID 5 for many reasons
(not the least of which is the trade off of disk space and the cost for
it), but to know that there was all this disparity (no pun intended)
over the manner in which the controller writes to the disk is nearly
laughable if not questionable. I have never heard of such things being
that bad in the past, but then again - I wasn't big on Oracle!


I'll let you know how my first endeavor goes. It's an OLTP system that is being readied for role out next week!


Best wishes to you, and keep the articles coming!

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Windows Clustering



Windows Clustering

A cluster is a group of independent computer systems, referred to as nodes, working together as a unified computing resource. A cluster provides a single name for clients to use and a single administrative interface, and it guarantees that data is consistent across nodes.
Windows Clustering encompasses two different clustering technologies. These technologies implement the following two types of clusters.
  • A network load balancing cluster filters and distributes TCP/IP traffic across a range of nodes, regulating connection load according to administrator-defined port rules.
  • A failover cluster provides high availability for services, applications, and other resources through an architecture that maintains a consistent image of the cluster on all nodes and that allows nodes to transfer resource ownership on demand.
The following are the programming interfaces for the Windows Clustering technologies:
  • The Network Load Balancing Provider allows developers to create remote administration and configuration tools as well as customized user interfaces for Network Load Balancing clusters.
  • The Failover Cluster APIs allow developers to create cluster-aware applications, implement high availability for new types of resources, and create remote administration and configuration tools.


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SMS: Microsoft Systems Management Server and Clustered Server Environments



SMS: Microsoft Systems Management Server and Clustered Server Environments


Article translations


Article ID: 237366 - View products that this article applies to.
This article was previously published under Q237366
: Microsoft Systems Management Server and Clustered Server Environments
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SMS
SUMMARY
This articles provides information on Microsoft Systems Management Server (SMS) and Clustered Server Environments.
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MORE INFORMATION
The SMS initial design did not include support for any form of clustered server; therefore services such as the SMS_Executive service were not written to handle the failure of a clustered system. For this reason, Microsoft does not support any version of SMS in a cluster server environment.

In SMS versions 1.x, clustered drives caused problems to several services on a site server, many of which were sub-threads of the SMS_Executive service. For this reason, SMS version 1.x was not supported on clustered servers. SMS version 1.x was designed to be able to recover on its own from certain failures. Among these are failures in communication with logon servers, clients, Intra-site, and so forth. Because SMS is also capable of using multiple Domain Controllers in a domain, logon server justification for clustering is not a valid option. SMS version 1.2 has many other redundancies built into the system that negate the use of a cluster system.

If SMS is using a Microsoft SQL Server Enterprise Edition server as a Logon Point, you may see failures to the Vsrvsvc.exe. If you are using SMS version 1.x, open the Administrator Console and confirm that Automatically Detect All Logon Servers is not selected. Maintenance Manager installs logon server components on the drive with the largest amount of free space, usually the clustered drive.

In SMS version 2.0, site system components such as site servers, Database, Distribution Points, Logon Points, and so forth, may not install successfully due to the presence of cluster server components on the system. If cluster server components are detected on the system, installation of these site systems will likely fail. The cluster server components merely need to be present and do not have to be implemented or operational in order for this to be true.

Chapter six of the SMS Administrator's Guide for version 2.0, titled "Installing Systems Management Server 2.0 Sites," only references Microsoft Windows NT Server version 4.0. If a cluster server component is detected during an installation, the installation will likely fail. If the installation is successful, site stability problems may begin to occur at any point.

There are problems between the cluster server services and the SMS services beyond the support of the Microsoft Product Support Services group. If two domain controllers are part of a server cluster, enabling either Windows Networking Logon Discovery or Windows Networking Logon Client Installation, this results in a system error on the site server. Because SMS detects the NTFS drive with the most free space, and this is likely to be the clustered drive, creation of the SMSLOGON share structure will likely fail. This could potentially cause site-wide problems.

The database for an SMS version 2.0 site, cannot be installed on a Microsoft SQL Server that is running either Microsoft Windows NT Enterprise Edition or Microsoft SQL Server Enterprise Edition with the cluster services enabled. Also, the SQL_Monitor_Agent will likely not install to a functional state if the cluster services are installed or enabled.

Windows NT Server 4.0 Enterprise Edition, Microsoft SQL Server 6.5, and Enterprise Editions 7.0 are not supported if the Cluster Services are installed or enabled. Microsoft SMS can install and configure these systems as client, distribution points, CAPs, site servers etc., if the cluster components have not been installed on the machine.

The SMS client components may be installed on one node of a cluster, as long as there is no attempt to utilize the shared drive space. If during troubleshooting of a client issue it is determined that the clustering services are causing or contributing to the failure, it will be recommended that the SMS client be removed from the system.

Some client installations fail on cluster nodes with the installation of the Web-Based Enterprise Management (WBEM) components. This is also because the WBEM components included in this version of SMS were not written to be cluster aware, and fail when they encounter the services.

Until the SMS components become cluster aware, support for this will begin with the elimination of the clustering services. This is an undesirable state that renders the cluster inoperable, therefore the SMS components are removed from the systems in the cluster.

See also the SMS version 2.0 Administrator's Guide, Appendix A, page 672.
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REFERENCES
For additional information about implementing SMS in a Microsoft Windows 2000-based clustered server environment, see the "Microsoft Windows 2000 Server Clustering Interoperability with SMS" white paper. To see this white paper, visit the following Microsoft Web site:
http://download.microsoft.com/download/2/7/b/27baeee3-429b-4bf3-9c1b-e69d7800a975/Clustering_W2K.doc
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Properties
Article ID: 237366 - Last Review: October 27, 2006 - Revision: 4.3

APPLIES TO
Microsoft Systems Management Server 1.0 Standard Edition
Microsoft Systems Management Server 1.1 Standard Edition
Microsoft Systems Management Server 1.2 Standard Edition
Microsoft Systems Management Server 2.0


Keywords: kbinfo KB237366

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Microsoft Hyper-V

Hyper-V

The Hyper-V role in Windows Server 2008 R2 and Windows Server 2008 provides software infrastructure and basic management tools that you can use to create and manage a virtualized server computing environment. More…

Get Started

Virtual PC Guy Blog Posts RSS

Hyper-V Forum Posts RSS

Featured Resources

Hyper-V Replica and Riverbed
This document captures the results from the bandwidth optimization experiments conducted in the Microsoft Engineering Excellence Center (EEC) lab by using the Riverbed Steelhead appliance WAN optimization devices with Windows Server 2012 Hyper-V Replica.
Hyper-V Dynamic Memory Configuration Guide
Dynamic Memory is a new Hyper-V feature in Windows Server 2008 R2 Service Pack 1 (SP1). This guide describes the requirements for evaluating Dynamic Memory and shows you how to configure and evaluate it. You also can watch theDynamic Memory video for a quick overview and demo of this feature.


Watch demonstrations and tutorials

These videos will help you to learn more about Hyper-V.
Windows Server 2012: How to Scale-Out a File Server by Using Hyper-V
Bob Hunt and Jose Barreto are back for today’s episode in which they show us how to scale-out a file server in Windows Server 2012 by using Hyper-V.		 Microsoft Virtual Academy: Importing a VM
This video shows the new virtual machine import tools in Windows Server 2012, and how raw XML configuration files can be imported without a prior export from Hyper-V.
 
Hyper-V Local vs. Hyper-V SMB Performance
Bob Hunt and Jose Barreto continue their Hyper-V over SMB series as they discuss a recently released independent study that compares the performance between Hyper-V local and Hyper-V over SMB.		 Virtualization and Cloud Experts Café: Hyper-V Backup
Harold Wong welcomes Product Strategy Specialist Chris Henley from Veeam as they chat about backing up Hyper-V VMs.
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