CE7490 2021 Fall - Advanced Topics in Distributed System - Project 2: RAID-6 based distributed storage system

RAID 6, also regarded as the double-parity RAID, is a RAID schemes that work by placing data on multiple disks and allowing input/output (I/O) operations to overlap in a balanced way, improving performance and offers redundancy to allow for disk failures within the RAID set and prevent data lost.

Raid6 is a great filesystem, we try to reimplement its userland tools quick and frienfly.

You can explore the bullit from either:

• Store and access abstract “data objects” across storage nodes using RAID-6 for fault-tolerance.
• Include mechanisms to determine failure of storage nodes.
• Carry out rebuild of lost redundancy at a replacement storage node.
• Accommodate real files of arbitrary size, taking into account issues like RAID mapping, etc.
• Support mutable files, taking into account update of the content, and consistency issues.
• Support larger set of configurations
• Read or write bigsize fileo bject by chunk mode
• Recover <=2 disks
• Detect 1 corrupted disk
• Find which disk is corrupted
• Mutable files
• Concurrent actual read/write
• Optimized and raw gf8 multiplication
• Our support data types can be text-only or arbitrary bytes

Basically it turns this:

• We set up a super node to interact with client and manage different request from users.
• We have three replica nodes for each master node, as shown in the orange node and blue nodes surrounded by the dashed circle in the Fig. For nodes other than super node, we employ Redundant Array of Independent Disks 6(RAID 6) to improve storage performance or reduce redundancy, or both.
• Meanwhile, for the services of each node to be more efficient, super node maintain a node info.json to record each node as well as the resources it has to try to choose nodes with more resources to save files.

The RAID-6 system is devloped in Python environment with corresponding dependencies.

The project is supported on Linux or MacOS.

Anaconda is a library that includes Python and many useful packages, as well as an environment manager called conda that makes package management simple.

Follow the official instrutions of Anaconda to install. Once it has been successfully installed, run the following command at terminal:

git clone https://github.com/ParsifalXu/Simple-Distributed-Storage-System.git
conda env create -f environment.yml

To use Python from the environment you just created, activate the environment with

conda activate RAID6

pip install -r requirements

Get into ./Nodes/node_1. node_2, node_3, node_4... as the same (you can only open 1 to 4 for test)

  cd  ./Nodes/node_1

Usage:   to start the super node_
  
   python ./superserver.py runserver
   -h, --help  

Run the server with:

$ python ./superserver.py runserver

INFO:     Uvicorn running on http://127.0.0.1:5000 (Press CTRL+C to quit)
INFO:     Started reloader process [28720]
INFO:     Started server process [28722]
INFO:     Waiting for application startup.
INFO:     Application startup complete.

Store and access abstract “data objects” across storage nodes using RAID-6 for fault-tolerance

Usage:  Get into ./Nodes/node_1. node_2, node_3, node_4... as the same (you can only open 1 to 4 for test)
    
open  'http://127.0.0.1:500%s/save' %node

If [node] is specified, save information into node_i filesystems.

node_info.json
  -h, --help                 display this message
  -d, --debug                enable debug output
  -node_info.json            quota of backup_node  & quota the save node 

• Mechanisms to determine failure of storage nodes
• Rebuild of the lost redundancy at a replacement storage node
• RAID-6 data recovery
• Analysis, synchronization mechanism and
• Disaster tolerance and recovery
• RAID-6 Data Recovery Analysis

RAID 6 uses 2 parity techniques to allow for up to 2 disks to become unreadable, an xor-based technique, and a Reed-Solomon-based one (which is based on Galois Fields). As a way to explore these I built this simple program based on a PDF from Kernel.org: https://www.kernel.org/pub/linux/kernel/people/hpa/raid6.pdf