Resize Hard Disk - Greyed Out / Have Snapshots for this VM - Unclear what deleting them will do to VM

[mattyww]

Hello,

I have a File Server VM here and Local Disk C is Full (40GB). I want to expand the volume size in VSphere but the option is greyed out, after doing some research I was able to find out that the 2 snapshots attached to this particular VM are the reason why I can't extend the volume.

My questions are:

• What happens to my VM if I delete the snapshots? (I was told by my friend that deleting them will render the VM useless)
  • one of them is 9.05 TB
  • the other is 25 MB
• Can I delete the snapshots while the VM is on?
• Do I need equivalent space (equal to the size of the snapshots) on my datastore to delete the snapshots?

The datastore still has 4.49 TB remaining

[scott28tt]

Your friend doesn’t know what they are talking about.

You would lose the ability to revert the VM to the state it was in when the snapshot was created.

That is a better situation than the one you face right now with a snapshot of that size! (you have not suffered any data loss)

I shall have to leave your questions to more knowledgeable folks... but watch out for rogue snapshots in the future, delete them when they are not needed (usually after a backup or upgrade completes)

[mattyww]

Hahaha, thank you Scott.

Can I delete that large snapshot right now without it affecting that server? Performance etc.

Also, the datastore it's housed on only has 4.49TB storage remaining and the snapshot is 9.03 TB.

Does this matter?

[scott28tt]

Those were the questions I am leaving to “more knowledgable folks”

However, I believe performance will definitely be impacted (there’s 9TB of data to be merged from your child disk to the parent disk), and whether you need free space or not depends on whether the virtual disks of the VM are thick provisioned or thin provisioned.

Whatever you do, make sure you have a backup first.

[mattyww]

Thanks again!

We have Veeam run nightly and it backs up of all our virtual machines, so I suspect it should be fine.

If anyone else can clarify what is best practice, I'd really appreciate it.

[IRIX201110141]

• Your friend is not exactly right. You will lose your data if you shutdown the VM and remove the snapshot file be going to the ESXi command line and deleting it. Than for sure you have lost your data
• VMware use the termin "Delete Snapshot" within the GUI and it does a merge/commit of your actual data back into old one. This is what you want to get rid of a Snapshot
• Please go to the command line and show us a  "ls -lisa"

Deleting a Snap can effect VM performance when you have a slow storage and you need to commt a lot of Data back.

Running a snapshot for a long time as you is a risk. Dont do it again.   I'll ask every customer if he will going go back in time  on its company main fileserver for half a year. Nobody want like to do,... so there is no reason for holding the snapshot.

You can press the "Delete all" within the GUI.

Regards,

Joerg

[a_p_]

Welcome to the Community,

Also, the datastore it's housed on only has 4.49TB storage remaining and the snapshot is 9.03 TB.

To find out whether there's enough disk space available to safely delete the snapshot, please do present the output of ls -lisa as asked for by IRIX201110141​.

With a 15TB datastore size, a ~9TB snapshot, and ~4.5TB free disk space, the VM's virtual disk must have been thin provisioned, which means that deleting the snapshot will require temporary disk space.

André

[mattyww]

Hi Team,

Thanks for your help so far!

Where do I run this ls -lisa command? via the command line ?

I have powerCLI and I can also remote in via ssh but not with the root account as I was not given the password and the guy who set it up is long gone.

Thanks again

[IRIX201110141]

cd FS03

please.

[IRIX201110141]

Can you share  "ls -lisah"? The 'h' is for human readable and make the numbers more clear.

Also a df -h  which show the datastore usage.  Btw. there is no need to create screenshots. Just use C&P.

Regards,

Joerg

[mattyww]

This is the output of ls -lisah

Thank you!

total 11282721024

   3524    128 drwxr-xr-x    1 root     root       92.0K Apr 30 13:11 .

      4   1024 drwxr-xr-t    1 root     root       72.0K Sep 13  2019 ..

25167044   3072 -rw-------    1 root     root        2.5M Sep 13  2019 -FS03-000001-ctk.vmdk

16778436  24576 -rw-------    1 root     root      181.0M Sep 13  2019 -FS03-000001-sesparse.vmdk

20972740      0 -rw-------    1 root     root         463 Sep 14  2019 -FS03-000001.vmdk

96470212   3072 -rw-------    1 root     root        2.5M Apr 30 13:06 -FS03-000002-ctk.vmdk

113247428 16177152 -rw-------    1 root     root       15.5G May  1 05:33 -FS03-000002-sesparse.vmdk

117441732      0 -rw-------    1 root     root         443 Apr 30 13:06 -FS03-000002.vmdk

   1220      0 -rw-r--r--    1 root     root        1.7K Sep 13  2019 -FS03-13d12057.hlog

62915780 16777216 -rw-------    1 root     root       16.0G Sep 13  2019 -FS03-Snapshot1237.vmem

67110084   2048 -rw-------    1 root     root        1.3M Sep 13  2019 -FS03-Snapshot1237.vmsn

109053124     64 -rw-------    1 root     root       19.5K Sep 13  2019 -FS03-Snapshot1238.vmsn

100664516      0 -rw-------    1 root     root          13 Sep 13  2019 -FS03-aux.xml

12584132   3072 -rw-------    1 root     root        2.5M Sep 13  2019 -FS03-ctk.vmdk

146801860 16777216 -rw-------    1 root     root       16.0G Jan 18 04:49 -FS03-f75025eb.vswp

4195524 37175296 -rw-------    1 root     root       40.0G Sep 13  2019 -FS03-flat.vmdk

54527172     64 -rw-------    1 root     root        8.5K Apr 30 13:06 FS03.nvram

8389828      0 -rw-------    1 root     root         641 Sep 13  2019 -FS03.vmdk

58721476      0 -rw-------    1 root     root         933 Apr 30 13:06 -FS03.vmsd

104858820      0 -rwxr-xr-x    1 root     root        3.1K Apr 30 13:06 -FS03.vmx

138413252      0 -rw-------    1 root     root           0 Jan 18 04:49 -FS03.vmx.lck

142607556      0 -rwxr-xr-x    1 root     root        3.1K Apr 30 13:06 -FS03.vmx~

50332868   5120 -rw-------    1 root     root        4.5M Sep 13  2019 -FS03_2-000001-ctk.vmdk

41944260   1024 -rw-------    1 root     root       36.3G Sep 13  2019 -FS03_2-000001-sesparse.vmdk

46138564      0 -rw-------    1 root     root         445 Sep 14  2019 -FS03_2-000001.vmdk

121636036   5120 -rw-------    1 root     root        4.5M Apr 30 13:06 -FS03_2-000002-ctk.vmdk

125830340 1531897856 -rw-------    1 root     root        1.5T May  1 05:32 -FS03_2-000002-sesparse.vmdk

130024644      0 -rw-------    1 root     root         452 Apr 30 13:11 -FS03_2-000002.vmdk

37749956   5120 -rw-------    1 root     root        4.5M Sep 13  2019 -FS03_2-ctk.vmdk

29361348 9663676416 -rw-------    1 root     root        9.0T Sep 13  2019 -FS03_2-flat.vmdk

33555652      0 -rw-------    1 root     root         571 Sep 13  2019 -FS03_2.vmdk

88081604   3072 -rw-------    1 root     root        2.3M Sep 13  2019 vmware-13.log

83887300  28672 -rw-------    1 root     root       27.3M Sep 13  2019 vmware-14.log

79692996   1024 -rw-------    1 root     root      304.0K Sep 13  2019 vmware-15.log

75498692  22528 -rw-------    1 root     root       21.7M Sep 13  2019 vmware-16.log

71304388   3072 -rw-------    1 root     root        2.6M Sep 13  2019 vmware-17.log

150996164   8192 -rw-r--r--    1 root     root        7.8M Jan 17 22:38 vmware-18.log

92275908   7168 -rw-r--r--    1 root     root        6.1M May  1 03:20 vmware.log

[mattyww]

This is the output of df -h

FS03 is located VOL4!!!

Filesystem   Size   Used Available Use% Mounted on

VMFS-5       8.0T   1.2T      6.8T  15% /vmfs/volumes/VOL1

VMFS-6      24.0T  20.2T      3.8T  84% /vmfs/volumes/VOL2

VMFS-6      15.0T   5.6T      9.4T  37% /vmfs/volumes/VOL3

VMFS-6      15.0T  10.5T      4.5T  70% /vmfs/volumes/VOL4

vfat       285.8M 205.8M     80.0M  72% /vmfs/volumes/55b70951-8359c070-ecb1d78a78d0

vfat       249.7M 173.1M     76.7M  69% /vmfs/volumes/361fd378-61a418af-b1bfb3d0242e

vfat       249.7M 172.8M     76.9M  69% /vmfs/volumes/9898347f-6c8107d8-11d9834ad2ee

vfat         4.0G  19.8M      4.0G   0% /vmfs/volumes/59cf0f06-19429230-f40343ac87b8

[IRIX201110141 · Accepted solution]

The snapshots are only around 1.5- 1.6TB in Total. So the value within the the snapshot manager is wrong or misleading.

So when your disks are already Thick than a Delete All doesnt need additional space. All changes will be written back into the original -flat.  See VMware Knowledge Base

You should start the snapshot deletion on a weekend. Dont worry about the progress bar when it hangs on 95 or 99% for ages.... let the process run.  You can calculate the needed time when using esxtop to check Read and Write values for the given LUN/Storage HBA.  If you get 80MB/s for writes than it should took up to 6h.  The timestamps on the files names are also updated during the process.

Regards,

Joerg

[continuum]

FS03_2-flat.vmdk can grow by 1.5 TB + a bit

FS03-flat.vmdk can grow by 16 GB + a bit

Both should fit but to consolidate  1.5 TB deltas while the VM is working you need some extra nerves - we are talking about half a year of data/ work.

You will sleep better when you do that while the VM is powered off.

If it helps - expanding your systemdisk after consolidating ONLY FS03.vmdk would probably take less than an hour of downtime ....

[continuum]

@ Joerg

sorry - had not seen your post and dont want to interact here if you are already looking into it ...

Ulli

[mattyww]

Thank you all for your help!

Is it possible to leave the VM powered while I delete the snapshot, we're concerned about it not powering on as we've been having issues with this server?

If you think it's best to turn it off, then I will do so.

[IRIX201110141]

Leave it on.  If possible dont create any kind of disk utilization when possible..  i mean if you use Windows Dedup be sure that no optimization or garbage collection runs during snapshot delete! Similar is a anti virus full scan.

If you shutdown the VM... you cannot start it again until the snapshot delete is done.   If you have some kind of downtime... like no user during night you can try to restart the VM and press F5/F8 to get the windows start menu. Now you can start snapshot delete but if there is a need you can start Windows OS.

Regards,

Joerg

[a_p_]

Although the question has already been correctly answered by IRIX201110141​, here's one more hint.

Make sure that backup doesn't kick in for that VM while "Delete All" snapshots is in progress, i.e. temporarily pause the backup job!

André

[mattyww]

Thank you all for your help!

Everything went to plan and is functioning

[agajjar]

• Power off the VM or schedule a maintenance window.
• Before deleting snapshots, ensure you have a recent backup of the VM.
• Address the unusually large snapshot size to avoid extended consolidation times.
• Monitor the consolidation process to address any unexpected issues.