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                                                                                                           **** SNAPMIRROR ****

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Notes:

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- Snapmirror is a disaster recovery solution. This is part of Netapp's Asynchronous disaster recovery

solution kit(ADR)

- Snapmirror is used to mirror the volumes across vservers within a cluster or across clusters. However,

to mirror across clusters, peering has to be done.

- Snapmirror volumes are of two types Load Sharing (LS) and Data Protection (DP).

- Target volume for mirror should be greater or equal in size to the source volume.

- Target volume for mirror should be of type DP to carryout mirroring.

- If the source disk is gone or corrupt, then the admin has to break the snampirror relation and then point

the vserver to the target volume (DP type).

  Breaking the snapmirror relation automatically converts the target vojume to RW type.

- Snampirror can be initiated manually or it can be scheduled to run at specific intervals eg: hourly

 

 

Creating a Snapmirror relation:

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Identify a source volume:

Eg: cluster-6070://bala_vserver/san_vol

 

 

Create a target volume:

cluster-6070::> vol create -vserver nfsvs -volume san_vol_dp -aggregate rtp11_aggr -size 50g -state

online -type DP // Remember the  target type must be DP and source type to be RW

 

 

Establish a Snapmirror relation:

cluster-6070::> snapmirror create -source-path cluster-6070://bala_vserver/san_vol -destination-path

cluster-6070://nfsvs/san_vol_dp -type DP

 

 

Manually Initialize Mirror:

cluster-6070::> snapmirror initialize -destination-path cluster-6070://nfsvs/san_vol_dp

 

 

Change the Snapmirror rule so that it triggers at specific schedule:

cluster-6070::*> snapmirror modify -destination-path cluster-6070://nfsvs/san_vol_dp -schedule hourly

 

 

Deleting the Snampirror rule:

cluster-6070::*> snapmirror delete -destination-path cluster-6070://nfsvs/san_vol_dp

 

 

Other Commands for Snapmirror management:

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Peering:

cluster peer create -peer-addrs 10.226.169.229

(Then, provide username and password of the cluster to join the peer)

Remember that the peer address should be the lif that holds the role as 'intercluster' or 'data'. In below

example, see "-role"

eg: cluster-6070::*> network interface create -vserver bala_vserver -lif data1 -role data -data-protocol

nfs,cifs -home-node sit-fas6070c-rtp03 -home-port e0a -address 10.226.169.229 -netmask 255.255.252.0

-status-admin up

 

 

View available snapshots:

cluster-6070::*> snapshot show -vserver bala_vserver -volume bala_vol1

 

 

Delete specific snapshot:

cluster-6070::*> snapshot delete -vserver bala_vserver -volume bala_vol1  hourly.2012-01-03_0905

 

 

Snapshots under DP volume cannot be tampered:

cluster-6070::*> snapshot delete -vserver nfsvs -volume san_vol_dp snapmirror.f5ed632a-cc0d-11df-

9db2-000e0caaf462_259_2147491351.2012-01-03_090501

Error: command failed: Snapshot copies can only be deleted on Read_Write (RW) volumes

 

 

To view the status of the snapmirror job:

cluster-6070::> job show 173174 -instance

 

 

To view the System stats while snapmirror operation is in progress:

cluster-6070::> statistics show-periodic

 

To break the Snapmirror relation (Check Snapmirror delete):

cluster-6070::*> snapmirror delete -destination-path cluster-6070://nfsvs/san_vol_dp (This will make the

snapmirror destination writable. When source is gone, this is useful for disaster recovery.)