Question

MongoDB backup error with volumegroup has insufficient space (0 extents)

  • 12 June 2023
  • 6 replies
  • 137 views

Userlevel 1
Badge +4

Hi All,

I’m trying to backup MongoDB and already installed and configured for backup. When I run backup, there is issue of volumegroup no space.

When I run the vgs command, the volumegroup did have 0 free space. However the FileSystem (LVM) space have plenty of free space. Can we utilize the LVM free space for the native snapshot?

Other than adding extra disk to extend the volumegroup, is there anyway that I can backup the MongoDB?

Its a sharded MongoDB using ubuntu.

Regards,

Fauzi


6 replies

Userlevel 6
Badge +15

Do you have at least 15% space available on the VG to hold the snapshot?  That is what is needed for snapshots in Linux.

Userlevel 1
Badge +4

Hi Orazan,

So I still need free space on VG not on LV? Do I need at least 5% as per documentation online or 15% free space of the VG?

The error I’ve got is for every node especially on the VG that hold the mongodata. Do I need to add extra space for every node? Do backup will be done from every node or how actually commvault backup the mongodb data? It is a sharded mongodb so it has replicas for each of the data for every node.

Regards,

Fauzi

Badge

Hi All,

I’m trying to backup MongoDB and already installed and configured for backup. When I run backup, there is issue of volumegroup no space.

When I run the vgs command, the volumegroup did have 0 free space. However the FileSystem (LVM) space have plenty of free space. Can we utilize the LVM free space for the native snapshot?

Other than adding extra disk to extend the volumegroup, is there anyway that I can backup the MongoDB?

Its a sharded MongoDB using ubuntu.

Regards,

Fauzi

Hi there,

 

Did you ever figure out an alternative to extending the VG?

Badge +4

Hi  @Fauzi Japri  could you please share    “ vgdisplay “  output.

after add  extra space to lvm  group .do not extend lv . just extend vg .that’s it

 

example  

 

1-- root@mongo0:~# fdisk  /dev/nvme0n2    

 

 

2 -- root@mongo0:~# pvcreate /dev/nvme0n2p1

  Physical volume "/dev/nvme0n2p1" successfully created.

 

3--

root@mongo0:~# vgextend vgubuntu /dev/nvme0n2p1

  Volume group "vgubuntu" successfully extended

 

 

root@mongo0:~# root@mongo0:~# vgdisplay

  --- Volume group ---

  VG Name              vgubuntu

  System ID

  Format                lvm2

  Metadata Areas        2

  Metadata Sequence No  4

  VG Access            read/write

  VG Status            resizable

  MAX LV                0

  Cur LV                2

  Open LV              2

  Max PV                0

  Cur PV                2

  Act PV                2

  VG Size              <84,49 GiB

  PE Size              4,00 MiB

  Total PE              21629

  Alloc PE / Size      12659 / <49,45 GiB

  Free  PE / Size      8970 / <35,04 GiB

 

DO NOT EXTEND LV 

 

 

 

 

Userlevel 1
Badge +4

Hi,

My server team already add another disk and add to the vg. This is not supposed to be done because when they setting up the server should not use up the vg when creating lv. 

 

regards,

Fauzi 

Badge +4

hi @Fauzi Japri 

This is exactly as it should be, this is not related to mongodb or commvault,  commvault mongodb baclup use native  block level if you want native block level backup, you have to use lvm snapshot, this is a linux feature, lvm snap is always created in vg, it requires at least 10% free space.

If you want to take lvm snap without using any backup software,  it works like this  (min %10 free space on vg )

 

regards

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