Hello demhyts
"Overreserved taking too much space...Is it normal?"
VxRails apply a Thick-provisioned Storage Policy to all service VMs (VxRail manager, vCSA, PSC, vRealize LogInsight) so likely a few of the TB are these.
.vswp files are also Thick-provisioned by default.
Disk Objects can also unintentionally be Thick as a result of using workflows that don't fully understand SPBM such as migrating/cloning VMs via the C# Thick Client.
"Any workaround to reduce the VM Overreserved capacity usage on VSAN?...appreaciate any advice, thank you"
Identify what Objects Thick-provisioned and Thin them - unfortunately re-applying the same SP(Storage Policy) won't work if it is Thick but the SP states OSR=0, in this case what I usually do is clone the current SP and add a rule for 'IOPS Limit=0', apply this SP to thin the Object (*shouldn't* cause full rebuild of the Object) and then either re-apply the original SP or leave it as is.
Identifying these Objects can be done in numerous ways using RVC, objtool+cmmds-tool or scripts against the data generated by vsan-health-status.pyc:
Save the vsan-health-status.pyc output:
# python ./usr/lib/vmware/vsan/bin/vsan-health-status.pyc > /tmp/Health.txt
Show all Thick Objects:
# for i in $(python ./usr/lib/vmware/vsan/bin/vsan-health-status.pyc | grep "'proportionalCapacity': 100" | awk '{print $2}'); do grep -A1 $i /tmp/Health.txt; done
Show all Thick Objects that are not FP=1(as .vswp are by default):
# for i in $(python ./usr/lib/vmware/vsan/bin/vsan-health-status.pyc | grep "'proportionalCapacity': 100" | grep -v "'forceProvisioning': 1" | awk '{print $2}'); do grep -A1 $i /tmp/Health.txt; done
Script a colleague of mine wrote to generate this information using objtool+cmmds-tool:
# for i in `cmmds-tool find -f python | grep 'proportionalCapacity\\\": 100' -B9 | grep uuid | cut -d "\"" -f4` ; do /usr/lib/vmware/osfs/bin/objtool getAttr -u $i | egrep '(^Object path:|^UUID:)' ; echo ; done
Setting .vswp default to Thin:
https://cormachogan.com/2016/02/22/vsan-6-2-part-5-new-sparse-vm-swap-object/
Bob
