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julyusmotyus
Contributor
Contributor

VSAN object format health

Hello¡¡

I have an alarm in Skyline Health of vSAN

 

julyusmotyus_0-1655204584271.png

I would like to know what object are those 5 objects that appear in the screenshot before changing the format.

Is it possible to know this?

I have read that by doing the process the performance of the cluster can be affected. Any other suggestions to take into account?

Thank you.

Best regards.

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TheBobkin
Champion
Champion

@julyusmotyus, they will be whichever objects are on object format version lower than v13 - these can be checked via RVC or via the output of:

# esxcli vsan debug object list --all

 

Re-layout of these generally only cause any kind of performance issues if the cluster is already being pushed near its limit and/or isn't very performant for large write tasks - that being said, resync IO fairness scheduler should limit the impact of this (unless network is the bottleneck and storage is quite fast) by adding latency to the resync IOs so that regular VM IOs get priority. If it is a huge proportion of the clusters data that needs to be processed then I generally advise customers to start this during relatively quieter times for the cluster (e.g. start on a Friday evening).

 

Only other thing to account for is that there is enough space to re-layout the largest object, this is typically only ever an issue in very small cluster (e.g. 2-nodes) where there are relatively large objects e.g. imagine a 2-node cluster with 10TB raw capacity per node but the only object on the cluster is a single 7TB (per replica) FTT=1 vmdk - this would temporarily require 7TB free space per node to re-layout and hence would not be possible and have to go with alternatives like temporarily setting it to FTT=0 re-layout and set back to FTT=1 or migrating it off vsanDatastore and back again.

 

 

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julyusmotyus
Contributor
Contributor

Hello,
Thank you for your reply

I have run the command but all the objects that appear are in version 15.

Is there any other option to see which objects will be migrated? Depending on which virtual machine may be affected I would have more or less margin to be able to perform the operation.

Thanks

Best regards.

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viquarhcimca
Enthusiast
Enthusiast

when u see the objects are in state 15 , its means 

state = 15 is rebuilding . 

 

please check if u have enough space to rebuild the objects ,if u dont have enough space then this state will not change. 

from the RVC u get the object uuid and run the below command to find the object owner 

cmmds-tool find -t HOSTNAME -f json -u <object uuid>   |grep content

Thanks & Regards,

Mohammed Viquar Ahmed
TheBobkin
Champion
Champion

@viquarhcimca while this was true on older versions this is not the case in current 6.7 and 7.0 releases - objects will only show a config status of 15 if they are in reduced-availability state, once resync for them has started they actually become state 7. Anyhow, this isn't a repair task so they would never be state 15 here.

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julyusmotyus
Contributor
Contributor

Hello,

All objects are in Healthy Availability, the versión of vSAN is 7.03.

Any more options to see these objects?

Thanks

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viquarhcimca
Enthusiast
Enthusiast

get help from gss 

Thanks & Regards,

Mohammed Viquar Ahmed
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viquarhcimca
Enthusiast
Enthusiast

got it paul thank you . 

Thanks & Regards,

Mohammed Viquar Ahmed
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