Skip to content

Latest commit

 

History

History
120 lines (89 loc) · 6.65 KB

vpools.md

File metadata and controls

120 lines (89 loc) · 6.65 KB

vPools

Introduction

A vPool is a Virtual Storage Pool, a single namespace used to deploy vDisks. A vPool can span multiple Storage Routers and connects to a single Storage Backend. The vPools overview lists all the vPools in the Open vStorage Cluster.

vPool Overview

The vPool overview lists all the vPools in the Open vStorage Cluster.

For each vPool following info is displayed:

  • Status: status of the vPool.
  • Name : Name of the vPool. You can click on the name of a vPool to see more details and execute actions.
  • Backend (Preset): ALBA Backend and used Preset of the Backend.
  • Stored Data: Total size of the current data and the Snapshots without the overhead imposed by the Backend redundancy.
  • IOPS: The current amount of IOPS delivered by the vPool to all vDisks.
Add new vPool
  • In case the GUI isn't open yet, open the Open vStorage GUI on the public IP of the Storage Router and enter with the default login and password: admin/admin.
  • Select from the menu vPools and click the Add new vPool button.

  • On the first tab

    • Enter a name for the vPool.
    • Select one of local Backends or an external Backend.
    • Select a Preset from the dropdown. This Preset defines how data is stored on the backend (e.f. 3-way replication). You can add more Presets in the detail page of a Backend. Once the vPool is created, you can not select a different Preset. The policy of the Preset can be updated.
    • Select the Amount of Proxies. Default is 2 for HA. More proxies might provide more bandwidth to the backend but as trade-off will consume more memory.
    • Select the Storage Router as Initial Storage Router and Storage IP on which the vPool is exposed. Click Next to continue.

  • On the second tab

    • Specify the fragment cache method
      • Select No Caching in case you have an all flash backend.
      • Select Read, Write or Read/Write depending on your application.
    • Select the location of the fragment cache
      • Select Place Fragment Cache on disk in case you want cache data on SSDs of the Storage Router with the read role. Typically you should select this option in case you are not using an ALBA backend with an SSD performance layer.
      • Specify the default vDisk cache Quota, the maximal amount of space (in GiB) the vDisk can occupy in the fragment cache. This can be overruled on individual vDisk level. Setting a cache Quota is only supported in the paying Enterprise Edition of Open vStorage.
      • Select Use another ALBA Backend as Fragment Cache to use an (all SSD) ALBA backend as cache layer to be used in front of the SATA backend.

  • On the third tab

    • Define the Distributed Transaction Log mode: Currently the DTL can be disabled (no DTL), synchronously (sync every 4K write) or asynchronously (sync on fsync from the VM).
    • Transport mode: TCP or RDMA (if available).
    • Select the SCO size (a collection of writes which gets stored on the Backend).
    • Select the Cluster Size, the block size used by the vDisks on the vPool.
    • Select the Write Buffer (the amount of data that can be in the DTL but not available in the Backend).

  • On the fourth tab

    • Validate the values and click Finish to complete.

Additional vPools can be added to the Storage Router by executing the same steps again.

vPool Details

The vPool Details page displays the detailed performance statistics of a single vPool. There are 2 types of statistics: Frontend and Backend statistics. The Frontend statistics are the performance metrics as seen by the vDisks. The Backend statistics are based on the data exchanged with the backend.

The Frontend details for a vPool are:

  • Status: status of the vPool.
  • Stored Data: Total size of the current data and the Snapshots without the overhead imposed by the Backend redundancy.
  • IOPS: The current amount of IOPS delivered by the vPool to all vDisks.
  • Read Speed: The current read speed for all vDisks on the vPool together.
  • Write Speed: The current write speed for all vDisks on the vPool together.

  • vDisks: The amount of vDisks on the vPool.

The Backend details for a vPool are:

  • Name: Name of the ALBA backend which is used to store the data.
  • Preset: USed ALBA Backend preset.
  • Login: Login for the Backend API.
  • Connections: Backend API Location.
  • Write Speed: The current write speed to the Storage Backend.
  • Read Speed: The current read speed from the Storage Backend.

The Configuration details for a vPool are:

  • SCO Size: The size of the Storage Conatiner Objects (a collection of writes) which gets stored on the Backend.
  • Cluster Size: The block size used by the vDisks on the vPool.
  • Volume Write Buffer: The amount of data that can be in the DTL but not available in the Backend.
  • DTL Mode: The way new writes are stored in the Distributed Transaction Log (DTL). The DTL is making sure that you don't have data loss when a host goes down. The DTL of a volume is configured on another host as where the volume is running and contains the outstanding writes (writes which are not yet on the backend). Every write to the write buffer (local SSDs) of a volume also gets transferred to the DTL on another host. This transfer can be disabled (no DTL), synchronously (sync every 4K write) or asynchronously (sync on fsync from the VM).
  • DTL Transport: Displays whether the vPool is using RDMA or standard TCP to transfer the DTL data.

These setting will be by default applied to all vDisks. The settings (except for the cluster size) can be changed on the individual vDisk Detail pages.

vPool Administration

vDisks

Under vDisks all vDisks served by the vPool are listed. To see more details of a vDisk, click its name.

vPool Management Actions
Storage Routers serving this vPool

All the Storage Routers which are currently serving this vPool are displaying the amount of proxies, default write buffer, used fragment and block cache. To add a Storage Router Click the + button next to the Storage Router name. To remove the vPool from a Storage Router click the trash can next to the Storage Router name. Removing a vPool from being served by a Storage Router is only possible in case there aren't any vDisks being served by the vPool on that Storage Router.

==== Info::Removing a vPool

To remove a vPool simply remove the vPool from all Storage Routers serving the vPool. Once the last Storage Router no longer serves the vPool, the vPool will automatically be deleted.