BIG-IQ Virtual Edition Disk Space Overview

F5 BIG-IQ Centralized Management Virtual Edition (VE) uses Logical Volume Management (LVM) to allow you to use utilities to resize file systems. Additional disk space is useful when you need more storage on your BIG-IQ system for things such as logging or database files.

If your BIG-IQ VE is part of a data collection device (DCD) cluster, you can view statistics about the resources each node uses by checking the BIG-IQ data collection cluster health. If your deployment does not include a DCD cluster, you can use tmsh commands to check the resources used by the BIG-IQ VE.

For details about checking available disk space on nodes in a DCD cluster, refer to Check disk space usage for DCD nodes on support.f5.com.

Here is an example that uses a tmsh command to check an initial installation of BIG-IQ version 5.2 VE with a single installation slot created on volume HD1.1

  [root@bigiq-console-test-large:Active:Standalone] ~ # tmsh show sys software 
  
  ----------------------------------------------------
  Sys::Software Status
  Volume  Product  Version     Build  Active    Status
  ----------------------------------------------------
  HD1.1    BIG-IQ    5.2.0  0.0.5741     yes  complete

The size of each file system is determined by a configuration file within the BIG-IQ installation image. (For details, refer to Default File System Sizes on support.f5.com.)

You can use the command lvs to see the file structure on your BIG-IQ VE. The response shows all of the default logical volumes created, along with their size, in kilobytes.

Here is an example of an a typical BIG-IQ version 5.2 VE file system.

  [root@bigiq-console-test-large:Active:Standalone] ~ # lvs --unit=k
  LV            VG        Attr      LSize        Pool Origin Data%  Move Log Cpy%Sync Convert
  dat.log.1     vg-db-sda -wi-ao---  7168000.00k
  dat.maint.1   vg-db-sda -wi-a----   307200.00k
  dat.share.1   vg-db-sda -wi-ao--- 10240000.00k
  dat.swapvol.1 vg-db-sda -wi-ao---  1048576.00k
  set.1._config vg-db-sda -wi-ao---  3321856.00k
  set.1._usr    vg-db-sda -wi-ao---  3452928.00k
  set.1._var    vg-db-sda -wi-ao--- 10485760.00k
  set.1.root    vg-db-sda -wi-ao---   450560.00k

Each installation volume has its own root, /usr, /config, and /var file systems. The file systems are mounted on logical volumes named using the following naming convention: vg--db--sda-set.<installation slot>.<file system alias>.

This table illustrates the mapping structure.

File System Details

This table describes the contents of a folder structure on a typical BIG-IQ® VE.

Default File System Sizes

The BIG-IQ® installation image contains the information used to configure logical volumes with default sizes. These default sizes are referred to as plans. If you install a new BIG-IQ version and the existing logical volumes in the target installation slot are not at least as large as the default size, then the installation process deletes and recreates the entire slot with the default logical volume sizes specified in the plan for the installation image. If you want to see the sizes defined in the plan for your BIG-IQ system, you can use a script named imageplan.

Here is an example of the plans defined for a BIG-IQ version 5.2 installation.

  [root@bigiq-console-test-large:Active:Standalone] ~ # imageplan /shared/images/BIG-IQ-5.2.0.0.0.5741.iso
product BIG-IQ version 5.2.0 build 0.0.5741 (BIGIQ520) selected
Standard plan
  Mount point: /, Size: 450000k
  Mount point: /usr, Size: 3450000k
  Mount point: /config, Size: 3320000k
  Mount point: /var, Size: 10485760k
Tiny plan
  Mount point: /, Size: 450000k
  Mount point: /usr, Size: 3450000k
  Mount point: /config, Size: 500000k
  Mount point: /var, Size: 10485760k

As illustrated in this example for BIG-IQ version 5.2, the Standard and Tiny plans use the same sizes for the/,/usr, and/var mount points. The size for the/config mount point often changes for each plan.

When you install BIG-IQ software, the installation process reads the plan for the version you are installing and then uses either the Standard or the Tiny plan depending upon the total disk size available in the target installation slot.

Resizing VE Disk Volume Workflows

The workflow for extending your disk volumes depends on whether you are performing a new installation or upgrading to a new version of BIG-IQ.

If you are installing a new BIG-IQ system:

• Determine how much disk space you have. If you need more physical disk space, attend to that first.
• Determine how much space you need on each of the volumes your BIG-IQ system uses.
• Create the correct volume sizes.
• If you want to facilitate upgrading this BIG-IQ system in the future, create an installation slot.

If you are upgrading a BIG-IQ system:

• Determine how much disk space you have. If you need more physical disk space, attend to that first.
• Determine how much disk space is required for the software you plan to install. F5 has a script that you can use to determine the correct volume sizes for the software you plan to install. imageplan reads the image plan for the software you plan to install and reports it on screen.
• If you have the disk space and an open slot, you can use an F5 script to create the new volumes required for the image you plan to install. addvol reads the image plan for the software you plan to install and creates the volumes required.
• If you have extended the disk space on your current installation, you can use an F5 script that increases volume size as needed. resizevol sets the volume size to the value you specify.
• If you need an extra slot, you can add it as part of the installation command. The create_volume parameter adds a new slot to your VE and (if you’ve set up the volume sizes correctly using addvol and resizevol) when the software upgrades, all of your data fits without any disk resizing. Resizing disks in the middle of an upgrade can cause you to lose data.

There are two sets of example tasks that guide you through the workflow for extending your disk size. Choose the example workflow that corresponds to your situation.