Appendix H. Mirror Management Console

Appendix H. Mirror Management Console

The mirror management console is provided only for the individual mirror resources managed by MCCS.
The mirror management console operates independently from the engine logic of MCCS, so during operation, it can collide with MCCS.
The mirror management console informs users of the mirror volume status and the capacity of the mirror in use. You can change the bandwidth and the mirror network addresses in it.

Table of Contents

 

Screen configuration

Mirror management screen

The following mirror management screen is used.

[Figure]  Mirror management screen

 

Mirror set configuration

 The mirror resource configured in MCCS is expressed as a single mirror set.

 

Figure

Description

Volume

The volume role is Source.
Displays the capacity in use on the right side of the volume. 

The volume role is Target.

Status

 

The status is Mirroring.

The status is Resyncing.
Displays the progress for resyncing.

The status is Paused.

There is a dirtybit in the volume.

Split brain occurred.

 

 

Mirror management command descriptions

Right click with your mouse button on the mirror set volume to see the descriptions of the mirror management commands that can be selected.

 

Menu

Description

Source

Pause

The mirror status will be changed to PAUSE and replication will be paused. 

Resync

The mirror status will be changed to RESYNCING and the full synchronization will be initiated between node.

Resume

Resume MIRRORING the mirror disk which was paused. Resynchronization will take place in advance, if there is data change during paused. 

Target

Lock

The volume is locked to prevent access the volume from the node.

Unlock

Unlock the target volume to access read only purpose. Mirror status should be paused in advance.

When you unlock the target volume, you can access the volume read only purpose. It can cause a negative effect to the mirror. 
Even if you unlock it, you cannot write to the disk. If you want to "write" to the disk, you must manually change the readOnly attributes in the registry. But it does not highly recommended to secure data integrity.

Descriptions of properties setting

[Figure] Mirror Management Screen

 

Attribute name

Description

JOB ID

JOB ID is displayed.

Bit Map

It is the directory containing the intent log.

Compression level

It represents the compression level for a specific copy set. The setting range is from 0 to 9.
‘0’ means no compression. The greater the value is, the smaller bandwidth is used to transmit greater data. But also, it uses more of the CPU resources.
Thus, by properly balancing the system CPU usage and the network bandwidth, select the proper compression level that can maximize the efficiency.

Empty async queue

Even if a driver receives a request for deleting a queue, this function can be used to prevent deletion of queues on a specific volume.

Bandwidth 

It is the max network bandwidth (kbps/sec) that can be used by a copy set.
‘0’ means that the given bandwidth will be used with maximum efficiency.

Mirror network address 

IP address of mirror disk between nodes in a cluster.