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Best Practices when using Mount Points in SQL Server

Follow the following best practices when using mount points with SQL Server standalone and failover cluster instances - Use the root (host) volume exclusively for mount points. The root volume is the volume that is hosting the mount points. This greatly reduces the time that it takes to restore access to the mounted volumes if you have to run a chkdsk. This also reduces the time that it takes to restore from backup on the host volume. If you use the root (host) volume exclusively for mount points, the size of the host volume only has to be several MB. This reduces the probability that the root volume will be used for anything other than the mount points. During failover cluster installation, use subdirectories under the root of mounted volumes to store database and backup files. For example, say you have a mounted volume F:\SQL1. This is the root of the mount point and you shouldn't use this location directly to store your database files. You should instead create a subdirect

Vendors of Columnar Database

Columnar technology was made popular by Sybase, now part of SAP, with its IQ product. Today, many other vendors have brought columnar database products to market, among them 1. 1010data, 2. Calpont, 3. Infobright, 4. ParAccel, 5. Sand Technology, 6. SenSage and 7. Vertica 8. Aster Data 9. Teradata EMC Greenplum and Oracle have added some columnar capabilities to their products

Disadvantages of using Columnar Database

Columnar databases do have their disadvantages. They are typically less efficient when it is necessary to update or delete data, for several reasons. First and foremost, updating or deleting a single row of data requires finding several locations on disk where the individual columns are stored. Even single row retrievals can be slower, resulting in a noticeable performance difference. Columnar databases can also be implemented as MPP (massively parallel processing) systems, as hardware appliances or as in-memory systems.

Benefits and Advantages of Columnar databases

Fundamentally, columnar database technology offers two primary benefits, increased speed and reduced storage requirements. Columnar organization yields several storage-related benefits as well. First, columnar databases make little or no use of user-defined indexes, so they require no additional storage other than that for the data. Second, once the data is sorted and stored by column, the potential for compression increases dramatically. Columnar databases not only can reduce the amount of storage required, but also in many cases can reduce the amount of memory required to process the data.

Columnar Database

The columnar databases store data by columns instead of rows. This means that all values of a single column are stored consecutively on disk. The columns are tied together as “rows” only in a catalog reference. This gives a much finer grain of control to the RDBMS data manager. It can access only the columns required for the query as opposed to being forced to access all columns of the row. It’s optimal for queries that need a small percentage of the columns in the tables they are in but suboptimal when you need most of the columns due to the overhead in attaching all of the columns together to form the result sets.

VMFS vs RDM

VMFS 1. Volume can host many virtual machines (or can be dedicated to one virtual machine). 2. Increases storage utilization, provides better flexibility, easier administration and management. 3. Large third-party ecosystem with V2P products to aid in certain support situations. 4. Does not support quorum disks required for third-party clustering software. 5. Fully supports VMware vCenter™ Site Recovery Manager (SRM). RDM 1. Maps a single LUN to one virtual machine so only one virtual machine is possible per LUN. 2. More LUNs are required, so it is easier to reach the LUN limit of 256 that can be presented to an ESX host. 3. Uses RDM to leverage array-level backup and replication tools integrated with SQL Server databases. 4. RDM volumes can help facilitate migrating physical SQL Server instances to virtual machines. 5. Required for third-party clustering software (e.g., MSCS). Cluster data and quorum disks should be configured with RDM. 6. Some customers use RDMs for

Database Administration tasks not to perform in Teradata

1. Never have to re-org data or index space 2. Never have to create Unix logins to match database logins 3. Never have to pre-allocate table/index space, format the partitions 4. Never have to pre-prepare data for loading (convert, sort, split, etc) 5. Never have to 'tune buffer' space 6. Never have to insure queries run in parallel 7. Never have to change the environment as the data grows 8. Never have to unload/reload data spaces due to expansion 9. Never have to design, implement and support physical partition schemes. 10. Never have to write programs to figure out how to divide up the data into partitions. 11. Never have to write or run programs to split the input data into partitions for loading 12. Never have to setup High Availability features (built-in)

VMDK vs RDM

RDM is recommended if you plan on using some of the special services provided by your SAN for this virtual machine; services such as: replication, snapshotting, or something like a virtual and physical node in a MSCS clustered pair. Otherwise stick with VMFS. There is virtually no performance difference and you retain the portability of your virtual machine. RDM is usually used in environments where they for example need very big fileserver storage

Infrastructure limitations ESX Server 4 vs ESXI 5

Some limitations in ESX Server 4 may constrain the design of data centers:[28][29] • Guest system maximum RAM: 255 GB • Host system maximum RAM: 1 TB[28] • Number of hosts in a high availability cluster: 32 • Number of Primary Nodes in ESX Cluster high availability: 5 • Number of hosts in a Distributed Resource Scheduler cluster: 32 • Maximum number of processors per virtual machine: 8 • Maximum number of processors per host: 160 • Maximum number of cores per processor: 12 • Maximum number of virtual machines per host: 320 • VMFS-3 limits files to 262,144 (218) blocks, which translates to 256 GB for 1 MB block sizes (the default) or up to 2 TB for 8 MB block sizes.[30] However, on a VMFS Boot drive, it is usually very difficult to use anything other than 1 MB Block size [31]. With ESXI 5 there has been some changes to these limits[32] • Guest system maximum RAM: 1 TB • Host system maximum RAM: 2 TB • Number of hosts in a high availability cluster: 32 • Maximum number

SQL Server 2012 Licensing

Three Main Editions 1. Enterprise 2. Business Intelligence 3. Standard Licensing Model 1. Server + Client Access License (CAL) 2. Core-based Enterprise: Only Core Based Business Intelligence: Server + Client Access License (CAL) Standard: Both

Microsoft SQL Server Core-Based Licensing

The Enterprise Edition and the Standard Edition of SQL Server 2012 will both be available under core-based licensing. Core-based licenses will be sold in two-core packs. To license a physical server properly, you must license all the cores in the server with a minimum of 4 core licenses required for each physical processor in the server. Core licenses will be priced at ¼ the cost of a SQL Server 2008 R2 (EE/SE) processor license.

User CAL.

A SQL Server User CAL is required in order for a user (employee, customer, partner, and so on) to access or use the services or functionality of Microsoft SQL Server. The Server plus user CAL model will likely be more cost effective if there are multiple devices per user ( for example, a user who has a desktop PC, laptop, PDA, and so forth ). A CAL is not software; it is a legal document granting a device or user access to server software. A single device CAL grants access to multiple servers for one device (CAL must be same version as latest version of any of the servers). A single user CAL grants access to multiple servers for one user.

Device CAL

A SQL Server Device CAL is required in order for a device (for example, a PC, workstation, terminal, PDA, mobile phone, and so on) to access or use the services or functionality of Microsoft SQL Server. The Server plus device CAL model will likely be the more cost-effective choice if there are multiple users per device ( for example, in a call center ). Please see multiplexing section to ensure every device is licensed properly. Exceptions include communication exclusively between SQL Servers and manual data transfer between employees.

SQL Server 2008 is available under three licensing models

Server plus device client access license (CAL). Requires a license for the computer running the Microsoft server product, as well as CALs for each client device. Server plus user client access license (CAL). Requires a license for the computer running the Microsoft server product, as well as CALs for each user. Processor license. Requires a single license for each CPU in the operating system environment running SQL Server. This license includes unlimited client device access.

How Does VMware DRS Work?

VMware® DRS aggregates computing capacity across a collection of servers into logical resource pools and intelligently allocates available resources among the virtual machines based on pre-defined rules that reflect business needs and changing priorities. VMware DRS allows users to define the rules and policies that decide how virtual machines share resources and how these resources are prioritized among multiple virtual machines. bring powered off hosts online once again to meet virtual machine requirements either at a pre-defined time or when it senses virtual machine requirements increasing.

What is VMware DPM?

VMware Distributed Power Management (DPM) is a pioneering new feature of VMware DRS that continuously monitors resource requirements in a VMware DRS cluster. When resource requirements of the cluster decrease during periods of low usage, VMware DPM consolidates workloads to reduce power consumption by the cluster. When resource requirements of workloads increase during periods of higher usage, VMware DPM brings powered-down hosts back online to ensure service levels are met. VMware DPM allows IT organizations to: • Cut power and cooling costs in the datacenter • Automate management of energy efficiency in the datacenter

What is VMware DRS?

VMware DRS dynamically balances computing capacity across a collection of hardware resources aggregated into logical resource pools, continuously monitoring utilization across resource pools and intelligently allocating available resources among the virtual machines based on pre-defined rules that reflect business needs and changing priorities. When a virtual machine experiences an increased load, VMware DRS automatically allocates additional resources by redistributing virtual machines among the physical servers in the resource pool. VMware DRS allows IT organizations to: • Prioritize resources to the highest value applications in order to align resources with business goals • Optimize hardware utilization automatically and continuously to respond to changing conditions • Provide dedicated resources to business units while still profiting from higher hardware utilization through resource pooling • Conduct zero-downtime server maintenance

VMware Distributed Resource Scheduler

VMware Distributed Resource Scheduler (DRS) aggregates computing capacity across a collection of servers into logical resource pools and intelligently allocates available resources among the virtual machines based on pre-defined rules that reflect business needs and changing priorities. VMware Distributed Power Management (DPM), included with VMware DRS, automates power management and minimizes power consumption across the collection of servers in a VMware DRS cluster.

Management Services

VMware vCenter Agent allows vSphere hosts to connect to vCenter Server for centralized management of all host and virtual machines. VMware vCenter Update Manager automates tracking, patching and updating for vSphere hosts, as well as applications and operating systems running in VMware virtual machines. VMware vCenter Converter allows IT administrators to rapidly convert physical servers and third-party virtual machines into VMware virtual machines

Application Services

VMware vMotion eliminates the need to schedule application downtime due to scheduled server maintenance through live migration of virtual machines across servers with no disruption to users or loss of service. VMware High Availability (HA) provides cost effective, automated restart within minutes for all applications in the event of hardware or operating system failures. Automatic detection of operating system failures. VMware HA detects operating system failures within virtual machines by monitoring heartbeat information. If a failure is detected, the affected virtual machine is automatically restarted on the server. In the event of physical server failure, affected virtual machines are automatically restarted on other production servers with spare capacity. In the case of operating system failure, VMware HA restarts the affected virtual machine on the same physical server. Hot plug virtual storage and network devices to or from virtual machines without disruption or dow

Infrastructure Services

VMware ESXi and ESX hypervisor architectures provide a robust, production-proven, high-performance virtualization layer that allows multiple virtual machines to share hardware resources with record-breaking performance that can match and in some cases exceed) native throughput. VMware Virtual SMP enables the use of ultra-powerful virtual machines that possess up to four virtual CPUs. VMware vStorage Virtual Machine File System (VMFS) allows virtual machines to access shared storage devices (FibreChanel, iSCSI, etc.), and is a key enabling technology for other vSphere components such as Storage vMotion. VMware vStorage APIs provide integration with supported third-party data protection solutions. VMware vStorage Thin Provisioning provides dynamic allocation of shared storage capacity, allowing IT organizations to implement a tiered storage strategy while reducing storage spending by up to 50 percent.

Key Features and Components

1. Infrastructure Services VMware ESXi™ and ESX® hypervisor architectures VMware Virtual SMP VMware vStorage Virtual Machine File System (VMFS) VMware vStorage APIs VMware vStorage Thin Provisioning 2. Application Services VMware vMotion VMware High Availability (HA) Hot plug Hot extend 3. Management Services VMware vCenter VMware vCenter Update Manager VMware vCenter Converter

What is VMware vSphere

VMware vSphere is the industry’s most complete, scalable and powerful virtualization platform, delivering the infrastructure and application services that organizations need to transform their information technology and deliver IT as a service.