The editlog snd fsimage are merged in the SNN to build a new fsimage The new

The editlog snd fsimage are merged in the snn to

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The editlog snd fsimage are merged in the SNN to build a new fsimage. The new fsimage is again loaded back in to the NN in step 3. Here .it is renamed as fsimage again in the NN.new editlog file also get created in to NN. Now the new editlog and newly created fsimage will be used by the NN to record the transaction. This is how checkpointing happens in HDFS. 12
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L INUX C OMMANDS Introduction Advantages of Linux Disadvantage of Linux Using Bash Features Understanding Linux File System To change the directory To create file To create a folder To list the contains of directory To copy files/directories To move files/Directories To remove files/directories To view the contents of the file Change the permission of the file and folder Process in Linux Compression in Linux 13 Chapter 2
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Introduction Computers were extremely expensive then, and sacrifices had to be made even after the original purchase just to get the users to understand how they worked. The total cost per unit of computing power was enormous In 1969, a team of developers in the Bell Labs laboratories started working on a solution for the software problem, to address these compatibility issues. They developed a new operating system, which was 1 Simple and elegant. 2 Written in the C programming language instead of in assembly code. 3 Able to recycle code. The Bell Labs developers named their project “UNIX." By the beginning of the 90s home PCs were finally powerful enough to run a full blown UNIX. Linus Torvalds, a young man studying computer science at the university of Helsinki, thought it would be a good idea to have some sort of freely available academic version of UNIX, and promptly started to code. Today Linux has joined the desktop market. Linux developers concentrated on networking and services in the beginning, and office applications have been the last barrier to be taken down. On the server side, Linux is well-known as a stable and reliable platform, providing database and trading services for companies like Amazon, the well-known online bookshop, US Post Office, the German army and many others. Especially Internet providers and Internet service providers have grown fond of Linux as firewall, proxy- and web server, and you will find a Linux box within reach of every UNIX system administrator who appreciates a comfortable management station. It is also worth to note that modern Linux not only runs on workstations, mid- and high-end servers, but also on "gadgets" like PDA's, mobiles, a shipload of embedded applications and even on experimental wristwatches. This makes Linux the only operating system in the world covering such a wide range of hardware. The idea behind Open Source software is rather simple: when programmers can read, distribute and change code, the code will mature. People can adapt it, fix it, debug it, and they can do it at a speed that dwarfs the performance of software developers at conventional companies. This
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