DNS:
A Domain Naming server is a hierarchical namespace structure designed to provide host to IP address name resolution and registration.
DNS ZONE TYPE
Forward lookup zone: resolves names to IP address.
Reverse lookup zone: resolves IP addresses to Host names.
AD INTEGRATED ZONE
AD–integrated DNS enables AD storage and replication of DNS zone databases. Windows 2000 & 2003 DNS servers which accommodates storing zone data in AD. When you configure a computer as a DNS server, zones are usually stored as text files on name servers — that is, all of the zones required by DNS are stored in a text file on the server computer. These text files must be synchronized among DNS name servers by using a system that requires a separate replication topology and schedule called a zone transfer However, if you use AD integrated DNS you configure a domain controller as a DNS name server, zone data is stored as an AD object and is replicated as part of domain replication.
STUB ZONE
A Stub zone is a read only copy of a zone that contains only those resources records necessary to identify the authoritative DNS servers for the actual zone. A stub zone is used to keep a parent zone aware of authoritative DNS servers for a delegated zone and thereby maintain DNS name resolution efficiently. A stub zone is conposed of (A), (NS), (SOA)
Types of DNS Records:
- A(Host): Represents a computer or device on the network. 'A'records are the most common and most used DNS records.
- PTR(Pointer): Used for finding the DNS name that corresponds to an IP address. The PTR is found only in the reverse lookup zone.
- NS(NameServer): The NS RRs facilitate delegation by identifying DNS servers for each zone. They appear in all forward and reverse look-up zones.
- SOA(Start Of Authority):The first record in any zone file is a SOA. the SOA identifies a primary DNS name server for the zone as the best source of information for the data within that zone and as an entity processing the updates for the zone.
- SRV(Service Record):indicates a network service offered by a host.
- CNAME(Alias):an alias is hostname that refers to another hostname.
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DHCP: Is a standard for simplifing management of host IP configuration.
SUPERSCOPE: Superscope is a administrative feature of DHCP server that you can create and manage through the DHCP console. Using a Superscope you can group multiple scopes as a single administrative entity.
DHCP Authorize: This procedure is usually only needed if you are running a DHCP server on a member server. In most cases, if you are installing a DHCP server on a computer also running as a domain controller, the server is automatically authorized the first time you add the server to the DHCP console.
SCOPE: DHCP scope is a poole of IP addresses which are offered to DHCP clients.
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FSMO ROLES IN ACTIVE DIRECTORY
• Schema Master: The schema master domain controller controls all updates and modifications to the schema. To update the schema of a forest, you must have access to the schema master. There can be only one schema master in the whole forest.
• Domain naming master: The domain naming master domain controller controls the addition or removal of domains in the forest. There can be only one domain naming master in the whole forest.
• Infrastructure Master: The infrastructure is responsible for updating references from objects in its domain to objects in other domains. At any one time, there can be only one domain controller acting as the infrastructure master in each domain.
• Relative ID (RID) Master: The RID master is responsible for processing RID pool requests from all domain controllers in a particular domain. At any one time, there can be only one domain controller acting as the RID master in the domain.
• PDC Emulator: The PDC emulator is a domain controller that advertises itself as the primary domain controller (PDC) to workstations, member servers, and domain controllers that are running earlier versions of Windows. For example, if the domain contains computers that are not running Microsoft Windows XP Professional or Microsoft Windows 2000 client software, or if it contains Microsoft Windows NT backup domain controllers, the PDC emulator master acts as a Windows NT PDC. It is also the Domain Master Browser, and it handles password discrepancies. At any one time, there can be only one domain controller acting as the PDC emulator master in each domain in the forest.
REPLICATION Replication is a process of sending update information for data that has changed in the directory to other domain controllers, as a Part of the AD planning an implementation process.
*2000/2003 uses MULTI-MASTER replication for the AD.
*Types of UPDATES: Add, Modify, ModifyDN, delete
*USN: Update sequence numbers
*GUID: Globally unique identifier
REPLICATION PARTITIONS:
Schema Partition: contains object and attribute definitions. In other words it contains a list of definitions that define what objects and attributes for those objects can exist in the AD.
Configuration partition: contains information about the physical structure of the AD, such as the sites and domains and where DC resides in the enterprise. It is replicated to all DC's in the tree or forest.
Domain partition: contains information about all AD objects that are specific to that domain, such as users, groups and other resources. All domain partition information is completely replicated to all domain controllers within the domain.
REPLICATION TOPOLOGY
KCC: Knowledge Consistency Checker
**KCC uses only RPC to communicate with the directory service.
Bridgehead server: A point where a connection leaves or enters a site.
BENIFITS
• Optimize replication for speed and bandwidth consumption between domain controllers.
• Locate the closest domain controller for client logon, services, and directory searches.
• Direct a Distributed File System (DFS) client to the server that is hosting the requested data within the site.
• Replicate the system volume (SYSVOL), a collection of folders in the file system that exists on each domain controller in a domain and is required for implementation of Group Policy
=============================================================
What is RAID?
ANS: Redundant Array of Inexpensive disk is a way to increase capaxity, performance and reliablility.
RAID0: (Striping) Not really RAID as it has no fault tolerance, Data is striped across all disks, Excelent read/write performance.
RAID1: (Mirroring) Need at least 2 drives, tolerates single drive failure, often used for OS drive or boot volume.
RAID5: Requires at least 3 drives, data and parity striped across all disks, can tolerate failure of any one disk without losing data but performance does degrade.
TCP/IP MODEL
Application Layer
Transport Layer
Internet
Network Interface
OSI MODEL
Application Layer
Presentation layer
Session layer
Transport Layer
Network Layer
Data-link Layer
Physical layer
Monday, June 16, 2008
Sunday, June 15, 2008
The Fastest Processor On Earth
IBM Launches Super Fast P6
Maybe IBM's new slogan should be "Got Speed?"The computer giant today launched Power6, the latest and clearly the fastest in its Power line of microprocessors. At 4.7 GHz, the dual-core Power6 processor doubles the speed of the previous generation Power5 while using nearly the same amount of electricity to run and cool it, according to IBM.IBM said the Power6 has achieved an unprecedented first place rank for four benchmarks, including TPC-C transaction processing benchmarks and SPEC results that measure Java performance."This is not about compiler tuning to get the best results, we have a very broad performance lead in industry standard applications like SAP," Brad McCreadie, IBM fellow and lead designer on the Power6, told internetnews.com.
Starting June 8, IBM will ship mid-range System p 570 servers based on the Power6. P570 system pricing starts at $60,000. Over the next year IBM plans to ship both higher and lower end servers based on Power6 as well as a blade server.As for competitive advantage, IBM said its new 2- to 16-core server offers three times the performance per core of the HP Superdome machine, based on the TPC-C benchmark. The processor speed of the Power6 chip is nearly three times faster than the latest HP Itanium processor that runs HP’s server line.Another performance measure IBM listed is that the processor bandwidth of the Power6 chip – 300 gigabytes per second -- could download the entire iTunes catalog of over 5 million songs in about 60 seconds – a speed it claimed is 30 times faster than HP's Itanium."It's the fastest out there and there's no increase in power requirements so that's two big check marks in IBM's favor," Nathan Brookwood, analyst with Insight64, told internetnews.com. "This is absolutely a play by IBM to gain more market share."IBM also hopes to tap the interest many companies have in saving on cost, energy and space by consolidation and virtualization. The 570 is being positioned by IBM as "the world's most powerful mid-range consolidation machine." In one example, IBM said it calculates 30 SunFire v890s could be consolidated into a single rack of the new IBM machine, saving more than $100,000 per year on energy costs.But Sun officials said the v890 is an outdated model and not a fair example. "Our lower range systems are now faster than that," Tom Atwood, group manager of Sun's Sparc enterprise server group, told internetnews.com.Atwood give credit to IBM for its benchmark achievements, but said performance records are "a leapfrog game" that no one company tends to hold for long. He also said the value of consolidation is about more than performance.For example, Sun's own M8000 line developed with Fujitsu, has the ability to hot swap memory and add resources without bringing the system down first. "We can add four new processors without stopping the production environment," said Atwood.IBM did announce a unique feature that gives customers the ability to move live virtual machines from one physical Unix server to another while maintaining continuous availability. Coined the Power6 Live Partition Mobility function, this technology -- currently in beta, with general availability planned for later this year -- enables customers to move active virtualized partitions without temporarily suspending them.The Power6 is also the first Unix microprocessor able to calculate decimal floating point arithmetic in hardware. Until now, IBM said calculations involving decimal numbers with floating decimal points were done using software. The built-in decimal floating point capability is of potential advantage to enterprises running complex tax, financial and ERP programs.The Power6 can also operate at low voltages thanks to a new method of chip design IBM said it employed that lets the same chip be used in low power blade environments as well as large, high-performance symmetric multiprocessing machines. The chip has configurable bandwidth, enabling customers to choose maximum performance or minimal cost.
Maybe IBM's new slogan should be "Got Speed?"The computer giant today launched Power6, the latest and clearly the fastest in its Power line of microprocessors. At 4.7 GHz, the dual-core Power6 processor doubles the speed of the previous generation Power5 while using nearly the same amount of electricity to run and cool it, according to IBM.IBM said the Power6 has achieved an unprecedented first place rank for four benchmarks, including TPC-C transaction processing benchmarks and SPEC results that measure Java performance."This is not about compiler tuning to get the best results, we have a very broad performance lead in industry standard applications like SAP," Brad McCreadie, IBM fellow and lead designer on the Power6, told internetnews.com.
Starting June 8, IBM will ship mid-range System p 570 servers based on the Power6. P570 system pricing starts at $60,000. Over the next year IBM plans to ship both higher and lower end servers based on Power6 as well as a blade server.As for competitive advantage, IBM said its new 2- to 16-core server offers three times the performance per core of the HP Superdome machine, based on the TPC-C benchmark. The processor speed of the Power6 chip is nearly three times faster than the latest HP Itanium processor that runs HP’s server line.Another performance measure IBM listed is that the processor bandwidth of the Power6 chip – 300 gigabytes per second -- could download the entire iTunes catalog of over 5 million songs in about 60 seconds – a speed it claimed is 30 times faster than HP's Itanium."It's the fastest out there and there's no increase in power requirements so that's two big check marks in IBM's favor," Nathan Brookwood, analyst with Insight64, told internetnews.com. "This is absolutely a play by IBM to gain more market share."IBM also hopes to tap the interest many companies have in saving on cost, energy and space by consolidation and virtualization. The 570 is being positioned by IBM as "the world's most powerful mid-range consolidation machine." In one example, IBM said it calculates 30 SunFire v890s could be consolidated into a single rack of the new IBM machine, saving more than $100,000 per year on energy costs.But Sun officials said the v890 is an outdated model and not a fair example. "Our lower range systems are now faster than that," Tom Atwood, group manager of Sun's Sparc enterprise server group, told internetnews.com.Atwood give credit to IBM for its benchmark achievements, but said performance records are "a leapfrog game" that no one company tends to hold for long. He also said the value of consolidation is about more than performance.For example, Sun's own M8000 line developed with Fujitsu, has the ability to hot swap memory and add resources without bringing the system down first. "We can add four new processors without stopping the production environment," said Atwood.IBM did announce a unique feature that gives customers the ability to move live virtual machines from one physical Unix server to another while maintaining continuous availability. Coined the Power6 Live Partition Mobility function, this technology -- currently in beta, with general availability planned for later this year -- enables customers to move active virtualized partitions without temporarily suspending them.The Power6 is also the first Unix microprocessor able to calculate decimal floating point arithmetic in hardware. Until now, IBM said calculations involving decimal numbers with floating decimal points were done using software. The built-in decimal floating point capability is of potential advantage to enterprises running complex tax, financial and ERP programs.The Power6 can also operate at low voltages thanks to a new method of chip design IBM said it employed that lets the same chip be used in low power blade environments as well as large, high-performance symmetric multiprocessing machines. The chip has configurable bandwidth, enabling customers to choose maximum performance or minimal cost.
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