Differences
This shows you the differences between two versions of the page.
| Both sides previous revisionPrevious revisionNext revision | Previous revision | ||
| learn:bigdata:name_node [2014/08/07 17:07] – [Contains] yehuda | learn:bigdata:name_node [2022/01/03 16:03] (current) – external edit 127.0.0.1 | ||
|---|---|---|---|
| Line 1: | Line 1: | ||
| ====== Name node ====== | ====== Name node ====== | ||
| + | see also [[Secondary name node]] | ||
| * :!: MOST IMPORATANT FOR CLUSTER! | * :!: MOST IMPORATANT FOR CLUSTER! | ||
| * in-memory location of every [[Data block]] in cluster / rack | * in-memory location of every [[Data block]] in cluster / rack | ||
| Line 5: | Line 6: | ||
| * FS Ops | * FS Ops | ||
| * Block Mapping | * Block Mapping | ||
| + | * Send cordinates to clients where to get the [[Data blocks]] and witch [[Data node]] | ||
| + | * [[Name node]] retrives every __3 secounds__ heart-bit from [[Data node]] | ||
| + | * If [[Name node]] not retrives from the [[Data node]] heart-bit more then __10 minutes__ [[Name node]] will consedure the [[Data node]] as a [[Dead node]] and the [[Name node]] start to replicate all [[Data blocks]] that has on a [[Dead node]] to other nodes | ||
| ===== Requriements ===== | ===== Requriements ===== | ||
| * Should have LOT OF RAM, LOT OF MEM, LOT OF POWER | * Should have LOT OF RAM, LOT OF MEM, LOT OF POWER | ||
| - | ===== Contains | + | ===== Structure |
| - | * Map - Snapshot of entire file system (in Memory) | + | * RAM |
| - | * Tracks all the files | + | * [[Edit log]] |
| - | * Tracks Replication value - can be configured by [[Replication factor]] | + | * [[fsImage]] |
| - | * [[Edit log]] - Track any client changes of information | + | * FILE |
| - | * When proccess of Reboot or [[Checkpoint]] the Datanode marges the Map and [[Edit log|Edit logs]] to [[fsImage]] | + | * [[fsImage]] |
| - | To keep presistnece | + | When proccess |
