VDisk Mirroring

VDisks can be mirrored / replicated to another QUADStor system. The contents of the mirror is identical to that of the source VDisk. Once a VDisk has been mirrored, subsequent mirror/replication operations will only copy changes to the source VDisk since the last mirror operation.

Setting up the remote QUADStor system

One the remote system install the QUADstor core and itf packages

NOTE: Only IPv4 addresses are supported. Host names and IPv6 addresses are not allowed

Create a file called /quadstor/etc/ndrecv.conf and add the following line

RecvAddr=<recv listening ipaddr>

For example

RecvAddr=10.0.13.6

In the above example, the system will bind to 10.0.13.6 for mirror data.

Ensure that the following ports are allowed for TCP traffic in your firewall configuration

9953
9955

Restart the quadstor service

Creating a mirror

On the source quadstor system run the following command

/quadstor/bin/qmirror -s <Source VDisk Name> -d <Destination VDisk Name> -r <Destination IP Address> -s <Source IP Address> -g <Destination Pool>

In the above command the Source VDisk Name is the name of the VDisk that needs to be mirrored, the Destination VDisk Name is the name of the VDisk that will be created on the remove quadstor system. Destination IP Address is the IPv4 address of the remote QUADStor System. Source IP Address is optional and if specified, that address is used as the source for sending mirror data. The Destination Pool specifies the pool to with the Destination VDisk belongs to. If Destination Pool is not specified, then the pool name of the source VDisk is used.

For example:

/quadstor/bin/qmirror -s FOO -d FOO -r 10.0.13.6 -g SSDPOOL

Listing mirror operations

/quadstor/bin/qmirror -l

To list and cleanup completed or error operations run

/quadstor/bin/qmirror -l -p

Canceling a mirror operation

/quadstor/bin/qmirror -c -s <Source VDisk Name>

For example

/quadstor/bin/qmirror -c -s FOO

Once a mirror operation has completed, if a mirror operation is run again on the source VDisk and for the same Destination VDisk and the same Destination IP Address, only changes to the Source VDisk since the last mirror operation are sent.

Mirror operations can fail if:

1. The Source VDisk already has a mirror/cloning operation in progress

2. The Source VDisk if of an older metadata format (The VDisk was created with a QUADStor software version 2.x.x)