Hadoop Multiple Choice Questions on “Hadoop Configuration”.
1. Which of the following class provides access to configuration parameters?
a) Config
b) Configuration
c) OutputConfig
d) None of the mentioned
Answer: b
Clarification: Configurations are specified by resources.
2. Point out the correct statement.
a) Configuration parameters may be declared static
b) Unless explicitly turned off, Hadoop by default specifies two resources
c) Configuration class provides access to configuration parameters
d) None of the mentioned
Answer: a
Clarification: Once a resource declares a value final, no subsequently-loaded resource can alter that value.
3. ___________ gives site-specific configuration for a given hadoop installation.
a) core-default.xml
b) core-site.xml
c) coredefault.xml
d) all of the mentioned
Answer: b
Clarification: core-default.xml is read-only defaults for hadoop.
4. Administrators typically define parameters as final in __________ for values that user applications may not alter.
a) core-default.xml
b) core-site.xml
c) coredefault.xml
d) all of the mentioned
Answer: b
Clarification: Value strings are first processed for variable expansion.
5. Point out the wrong statement.
a) addDeprecations adds a set of deprecated keys to the global deprecations
b) configuration parameters cannot be declared final
c) addDeprecations method is lockless
d) none of the mentioned
Answer: b
Clarification: Configuration parameters may be declared final.
6. _________ method clears all keys from the configuration.
a) clear
b) addResource
c) getClass
d) none of the mentioned
Answer: a
Clarification: getClass is used to get the value of the name property as a Class.
7. ________ method adds the deprecated key to the global deprecation map.
a) addDeprecits
b) addDeprecation
c) keyDeprecation
d) none of the mentioned
Answer: b
Clarification: addDeprecation does not override any existing entries in the deprecation map.
8. ________ checks whether the given key is deprecated.
a) isDeprecated
b) setDeprecated
c) isDeprecatedif
d) all of the mentioned
Answer: a
Clarification: Method returns true if the key is deprecated and false otherwise.
9. _________ is useful for iterating the properties when all deprecated properties for currently set properties need to be present.
a) addResource
b) setDeprecatedProperties
c) addDefaultResource
d) none of the mentioned
Answer: b
Clarification: setDeprecatedProperties sets all deprecated properties that are not currently set but have a corresponding new property that is set.
10. Which of the following adds a configuration resource?
a) addResource
b) setDeprecatedProperties
c) addDefaultResource
d) addResource
Answer: d
Clarification: The properties of this resource will override the properties of previously added resources unless they were marked final.