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c# - Usage of Server Side Controls in MVC Frame work -

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i using asp.net 4.0 , mvc 2.0 web application. project requiremrnt have use server side control in application not possibl in noraml case. ideally want use adrotator control , datalist control. i saw few samples , references in codepleax mvc controllib howwver found less useful. can tell how utilize theese controls in asp.net application along mvc. note: please provide functionalities related adrotator , datalist controls not equivalent functionalities thanks in advace. mvc pages not use normal .net solution makes use of normal .net components impossible. a normal .net page use event driven solution call different methods service side mvc use actions , view completly different way handle things. also, mvc not use viewstate normal .net controlls require. found article discussing mixing of normal .net , mvc.
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mapreduce - Hadoop namenode : Single point of failure -

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the namenode in hadoop architecture single point of failure.

how people have large hadoop clusters cope problem?.

is there industry-accepted solution has worked wherein secondary namenode takes on in case primary 1 fails ?

yahoo has certain recommendations configuration settings @ different cluster sizes take namenode failure account. example:

the single point of failure in hadoop cluster namenode. while loss of other machine (intermittently or permanently) not result in data loss, namenode loss results in cluster unavailability. permanent loss of namenode data render cluster's hdfs inoperable.

therefore, step should taken in configuration namenode metadata

facebook uses a tweaked version of hadoop data warehouses; has some optimizations focus on namenode reliability. additionally patches available on github, facebook appears use avatarnode switching between primary , secondary namenodes. dhruba borthakur's blog contains several other entries offering further insights namenode single point of failure.

edit: further info facebook's improvements namenode.


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