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MaNikhilho's avatar
Icon for Altostratus rankAltostratus
Mar 15, 2021

Virtual Edition, TMSH shows 74gb, web GUI shows 24 gb

In all the lab setups we have created, the system uses 74gb, which is also verified by the TMSH df -h.

On the resource provisioning, it shows that disk space is only 24 gb, which corresponds to the 25 gb in the appdata, but tmsh shows that 19% is used while resource provisioning shows that almost 99% is used.

I havent been able to understand this, nor fix this by expanding the disk space


2 Replies

  • eey0re's avatar
    Icon for Cirrostratus rankCirrostratus

    74GB is the whole disk. BIG-IP uses Linux Logical Volume Manager (LVM) to create the logical volumes (LVs) for the software (aka boot locations), and shared volumes such as appdata.

    You can see the Physical Volume with the "pvs" command. You will see it is approx 74GB.

    [admin@bigip:Active:Standalone] ~ # pvs
      PV         VG        Fmt  Attr PSize  PFree
      /dev/sda3  vg-db-vda lvm2 a--  75.79g 9.17g

    This is also the size of the one Volume Group ("vgs" command). Note there is some free space, not allocated to any logical volume.

    [admin@bigip:Active:Standalone] ~ # vgs
      VG        #PV #LV #SN Attr   VSize  VFree
      vg-db-vda   1  13   0 wz--n- 75.79g 9.17g

    Within the volume group are the logical volumes ("lvs" command) which contain the actual filesystems, including the 25GB "appdata" volume:

    [admin@bigip:Active:Standalone] ~ # lvs
      LV            VG        Attr       LSize    Pool Origin Data%  Meta%  Move Log Cpy%Sync Convert
      dat.appdata   vg-db-vda -wi-ao----   24.92g
      dat.log       vg-db-vda -wi-ao----    2.93g
      dat.maint.1   vg-db-vda -wi-a-----  300.00m
      dat.share     vg-db-vda -wi-ao----   15.00g
      dat.swapvol   vg-db-vda -wi-ao---- 1000.00m
      set.1._config vg-db-vda -wi-ao----    2.17g
      set.1._usr    vg-db-vda -wi-ao----    5.15g
      set.1._var    vg-db-vda -wi-ao----    3.00g
      set.1.root    vg-db-vda -wi-ao----  440.00m
      set.2._config vg-db-vda -wi-a-----    2.17g
      set.2._usr    vg-db-vda -wi-a-----    5.15g
      set.2._var    vg-db-vda -wi-a-----    4.00g
      set.2.root    vg-db-vda -wi-a-----  440.00m

    (Those set.1 and set.2 volumes are the Boot Locations HD1.1, HD1.2.)

    The 99% of 24GB disk space shown in Resource Provisioning is the estimated maximum space your modules may grow to need. In theory they should manage themselves to remain under that size. (In practice, in some extreme cases they may not.)

    The 19% is how much of the appdata filesystem they are currently using. 19% used is quite healthy, and I would not be worried. You should have logging to look out for logs from diskmonitor should any volume's used space cross thresholds.

    See K8865: Overview of the diskmonitor utility

    Clearly from the logical volumes above you can see there is lots more space in the 74GB PV to grow. You can use that space for additional Boot Locations (as simply as typing a new number for Volume set name when installing a software image), or if you did need to grow appdata you can do that using "modify /sys disk directory /appdata" tmsh commands. (Note that you can only increase the size, not shrink it, so be sure this is what you want.)

    See K14952: Extending disk space on BIG-IP VE