Moving VDisks

Sometimes you may need to free up a block store volume to replace equipment. Or a VDisk may be in active use, affecting the performance of other VDisks running on the same PDisk. In cases like this, VDisks need to be moved.

Move a VDisk from a block store volume

Get a list of VDisk IDs using YDB DSTool:

ydb-dstool -e <bs_endpoint> vdisk list --format tsv --columns VDiskId --no-header

To move a VDisk from a block store volume, run the following commands on the cluster node:

ydb-dstool -e <bs_endpoint> vdisk evict --vdisk-ids VDISK_ID1 ... VDISK_IDN
ydbd admin bs config invoke --proto 'Command { ReassignGroupDisk { GroupId: <Storage group ID> GroupGeneration: <Storage group generation> FailRealmIdx: <FailRealm> FailDomainIdx: <FailDomain> VDiskIdx: <Slot number> } }'

• VDISK_ID1 ... VDISK_IDN: The list of VDisk IDs like [GroupId:GroupGeneration:FailRealmIdx:FailDomainIdx:VDiskIdx]. The IDs are separated by a space.
• GroupId: The ID of the storage group.
• GroupGeneration: Storage group generation.
• FailRealmIdx: Fail realm number.
• FailDomainIdx: Fail domain number.
• VDiskIdx: Slot number.

Move VDisks from a broken/missing block store volume

If SelfHeal is disabled or fails to move VDisks automatically, you'll have to run this operation manually:

1. Go to monitoring and make sure that the VDisk has actually failed.

2. Get the appropriate [NodeId:PDiskId] using YDB DSTool:

   ydb-dstool -e <bs_endpoint> vdisk list | fgrep VDISK_ID
   

3. Move the VDisk:

   ydb-dstool -e <bs_endpoint> pdisk set --status BROKEN --pdisk-ids "[NodeId:PDiskId]"
   

Enable the VDisk back after reassignment

To enable the VDisk back after reassignment:

1. Go to monitoring and make sure that the VDisk is actually operable.

2. Get the appropriate [NodeId:PDiskId] using YDB DSTool:

   ydb-dstool -e <bs_endpoint> pdisk list
   

3. Enable the PDisk back:

   ydb-dstool -e <bs_endpoint> pdisk set --status ACTIVE --pdisk-ids "[NodeId:PDiskId]"