VMFS iSCSI Volume Sizing

vcitenterprise — Thu, 05 Jun 2025 07:08:16 GMT

I've got a questions about our VMFS datastores. We have two LUNs for our Vmware Datastores both residing on the same Volume (vmfs1)

/vol/vmfs1/lun0	iscsi.datastore1	1.7T	online	vmware_igroup1 : 0
/vol/vmfs1/lun1	iscsi.datastore2	1.7T	online	vmware_igroup1 : 1

both residing on the same Volume (vmfs1)

Name:	vmfs1
Type:	Flexible	Root Volume?	-
FlexClone ?	-	Containing Aggregate:	aggr0
Status:	online,raid_dp,sis
Used Capacity:	1.12 TB	Space Guarantee	volume
% Used:	66%	Language:	en
Total Capacity:	1.7 TB	Total Size:	1.7 TB
Number of Files:	125	Max Directory Size:	17.9 MB
Max Files:	31.9 m
SNAP Mirror?	-	SNAP Directory?	-
SNAP?	-	Resync SNAP Time:	60
SVO Enable?	-	SVO Checksum?	-
Allow SVO RMAN?	-	SVO Reject Errors?	-
Create Unicode?	-	Convert Unicode?	-
Minimal Read Ahead?	-	NV Fail?	-
Fractional Reserve :	100	Extent?	-
FS Size Fixed?	-	Update Access time?
I2P?		Ignore Inconsistent??	-

What I'm scared of here is that we have a 1.7TB volume with two 1.7TB LUNS on it that are both almost full and Netapp is only reporting 66% usage. Shouldnt the volume be 2x 1.7TB to be sized correctly?

Re: VMFS iSCSI Volume Sizing

mkopenski — Tue, 21 Sep 2010 11:19:02 GMT

Looks like A-sis(advanced single-instance storage) is enabled for the volume.

What is the output of df -hs ? This will tell you the savings from A-sis

Re: VMFS iSCSI Volume Sizing

vcitenterprise — Tue, 21 Sep 2010 18:32:52 GMT

Thanks for the tip. I wasn’t aware that we had A-sis going yet. 50% dedup explains the sizing perfectly.

/vol/vmfs1/ 1161GB 1176GB 50%

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VMFS iSCSI Volume Sizing

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