CLI Guide

CAUTION: Use this command only if the resulting device will be initialized using tools on the host.
Do not use this command if one leg of the resulting device contains data that must be preserved. Applications
using the device may corrupt the pre-existing data.
To create a device when one leg of the device contains data that must be preserved, use the device attach-mirror
command to add a mirror to the leg. The data on the leg will be copied automatically to the new mirror.
The individual local devices may include any underlying type of storage volume or geometry (RAID 0, RAID 1, or RAID C), but
they should be the same capacity.
If a distributed device is configured with local devices of different capacities:
● The resulting distributed device is only as large as the smaller local device
● The leftover capacity on the larger device is not available
To create a distributed device without wasting capacity, choose local devices on each cluster with the same capacity.
The geometry of the new device is automatically RAID 1.
Each cluster in the metro node can contribute a maximum of one component device to the new distributed device.
This command can fail if there is not a sufficient number of meta volume slots. See the troubleshooting section of the metro
node procedures in the SolVe Desktop for a resolution to this problem.
CAUTION: If there is pre-existing data on a storage-volume, and the storage-volume is not claimed as being
application consistent, converting an existing local RAID device to a distributed RAID using the ds dd create
command will not initiate a rebuild to copy the data to the other leg. Data will exist at only one cluster. To
prevent this, do one of the following:
1. Claim the disk with data using the application consistent flag
2. Create a single-legged RAID 1 or RAID 0 and add a leg using the device attach-mirror command.
Use the set command to enable/disable automatic rebuilds on the distributed device. The rebuild setting is immediately applied
to the device.
● set rebuild-allowed true starts or resumes a rebuild if mirror legs are out of sync.
● set rebuild-allowed false stops a rebuild in progress.
When set to true, the rebuild continues from the point where it was halted. Only those portions of the device that have not
been rebuilt are affected. The rebuild does not start over.
Examples
In the following example, the ds dd create command creates a new distributed device with the following attributes:
● Name: ExchangeDD
● Devices:
○ /clusters/cluster-2/devices/s6_exchange
○ /clusters/cluster-1/devices/s8_exchange
● Logging volumes:
○ /clusters/cluster-1/system-volumes/cluster_1_loggingvol
○ /clusters/cluster-2/system-volumes/cluster_2_loggingvol
● Rule-set: rule-set-7a
VPlexcli:/distributed-storage/distributed-devices> ds dd create --
name ExchangeDD --devices /clusters/cluster-2/devices/s6_exchange,/clusters/
cluster-1/devices/s8_exchange --logging-volumes /clusters/cluster-1/system-volumes/
cluster_1_loggingvol,/clusters/cluster-2/system-volumes/cluster_2_loggingvol --rule-
set rule-set-7a
In the following example, the ds dd create command creates a distributed device, and with the default rule-set:
VPlexcli:/> ds dd create --name TestDisDevice --devices /clusters/cluster-1/devices/
TestDevCluster1, /clusters/cluster-2/devices/TestDevCluster2
Distributed-device 'TestDisDevice' is using rule-set 'cluster-2-detaches'.
Commands
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