Question : You need to set up a distributed storage system for being able to process very large data sets and you want to be able to leverage the Open Data Platform (ODP) Core. Which one of the following would you use? 1. Apache Spark
Correct Answer : Get Lastest Questions and Answer : Explanation: GPFS provides high performance by allowing data to be accessed over multiple computers at once. Most existing file systems are designed for a single server environment, and adding more file servers does not improve performance. GPFS provides higher input/output performance by striping blocks of data from individual files over multiple disks, and reading and writing these blocks in parallel. Other features provided by GPFS include high availability, support for heterogeneous clusters, disaster recovery, security, DMAPI, HSM and ILM.
According to (Schmuck and Haskin), a file that is written to the filesystem is broken up into blocks of a configured size, less than 1 megabyte each. These blocks are distributed across multiple filesystem nodes, so that a single file is fully distributed across the disk array. This results in high reading and writing speeds for a single file, as the combined bandwidth of the many physical drives is high. This makes the filesystem vulnerable to disk failures -any one disk failing would be enough to lose data. To prevent data loss, the filesystem nodes have RAID controllers " multiple copies of each block are written to the physical disks on the individual nodes. It is also possible to opt out of RAID-replicated blocks, and instead store two copies of each block on different filesystem nodes.
Other features of the filesystem include
Distributed metadata, including the directory tree. There is no single "directory controller" or "index server" in charge of the filesystem. Efficient indexing of directory entries for very large directories. Many filesystems are limited to a small number of files in a single directory (often, 65536 or a similar small binary number). GPFS does not have such limits. Distributed locking. This allows for full Posix filesystem semantics, including locking for exclusive file access. Partition Aware. A failure of the network may partition the filesystem into two or more groups of nodes that can only see the nodes in their group. This can be detected through a heartbeat protocol, and when a partition occurs, the filesystem remains live for the largest partition formed. This offers a graceful degradation of the filesystem " some machines will remain working. Filesystem maintenance can be performed online. Most of the filesystem maintenance chores (adding new disks, rebalancing data across disks) can be performed while the filesystem is live. This ensures the filesystem is available more often, so keeps the supercomputer cluster itself available for longer. It is interesting to compare this with Hadoop's HDFS filesystem, which is designed to store similar or greater quantities of data on commodity hardware " that is, datacenters without RAID disks and a Storage Area Network (SAN).
HDFS also breaks files up into blocks, and stores them on different filesystem nodes. HDFS does not expect reliable disks, so instead stores copies of the blocks on different nodes. The failure of a node containing a single copy of a block is a minor issue, dealt with by re-replicating another copy of the set of valid blocks, to bring the replication count back up to the desired number. In contrast, while GPFS supports recovery from a lost node, it is a more serious event, one that may include a higher risk of data being (temporarily) lost. GPFS supports full Posix filesystem semantics. HDFS and GFS do not support full Posix compliance. GPFS distributes its directory indices and other metadata across the filesystem. Hadoop, in contrast, keeps this on the Primary and Secondary Namenodes, large servers which must store all index information in-RAM. GPFS breaks files up into small blocks. Hadoop HDFS likes blocks of 64 MB or more, as this reduces the storage requirements of the Namenode. Small blocks or many small files fill up a filesystem's indices fast, so limit the filesystem's size.
Question : In traditional SAN based storage, to provide High Availability for the data , RAID (redundant array of independent disks) were used.
About RAID : RAID is a data storage virtualization technology that combines multiple physical disk drive components into a single logical unit for the purposes of data redundancy, performance improvement, or both.
Similar protection have been introduced in Hadoop Distributed File System . Which is known as a
Correct Answer : Get Lastest Questions and Answer : Explanation: Hadoop Distributed File System (HDFS) stores files as data blocks and distributes these blocks across the entire cluster. As HDFS was designed to be fault-tolerant and to run on commodity hardware, blocks are replicated a number of times to ensure high data availability.
Question : You are working with a storage company, which is helping a market reasearch company, which is having access to billions of record. However, this reaserch comapny is looking for a solution, where they can store this billions of records for some temporary days like 90 days until their analysis finishes and also want to run analytics on that data. which of the solution recommended from IBM 1. BigInsight
Correct Answer : Get Lastest Questions and Answer : Explanation: IBM PureData System for Analytics is a purpose-built, standards-based data warehouse and analytics appliance that integrates database, server, storage and analytics into an easy-to-manage system. It is designed for high-speed analysis of big data volumes, scaling into the petabytes.
Fast analytics : Provides a high-performance, massively parallel system that enables you to gain insight from your data and perform analytics on very large data volumes.
Smart, efficient queries: Simplifies analytics by consolidating all activity in one place, where the data resides.
Simplified infrastructure : Easy to deploy and manage; simplifies your data warehouse and analytic infrastructure. Does not require tuning, indexing or aggregated tables and needs minimal administration.
Advanced security : Enhanced data security is provided through self-encrypting drives as well as support for the Kerberos authentication protocol.
Integrated platform : Supports thousands of users, unifying data warehouse, Hadoop and business intelligence with advanced analytics.