which of the following is true or false ? and explain in short?
a) Fencing is used in namenode federation to prevent namenodes from changing each namespace metadata?
b) in mapreduce 2, progress tracking is handled by application master rather than the daemon , the resource manager.
1. True
explaination - Fencing is a mechanism which helps in preventing any previously active node to cause any damage or corruption in case of ungraceful failover. Multiple fencing mechanisms like killing the namenode’s process, revoking the access to the shared storage directory by using a vendor-specific NFS command), and disabling the network port via remote management command.
2. False
Total 5 daeomns are there in Mapreduce 2.0.
1. NameNode
2. Secondary Namenode
3. Resoruce manager
4. YARN components(REsoruce Manager/Node Manager)
5. Node Manager
Get Answers For Free
Most questions answered within 1 hours.