Sak

• May 31st, 2007

 

Cliques are group of nodes. Vdisk is group of disks virtually connected together and amp is assinged one set of Vdisk to work with. An amp will be responsible for one VDISK.

Neelima Dahi

• Aug 10th, 2007

 

A clique is a set of Teradata nodes that share a common set of disk arrays. Cabling a subset of nodes to the same disk arrays creates a clique.

Each AMP vproc must have access to an array controller, which in turn accesses the physical disks. AMP vprocs are associated with one or more ranks
(or mirrored pairs) of data. The total disk space associated with an AMP is called a vdisk. A vdisk may have up to three ranks. Hence Vdisk will communicate with physical storage through array controllers.

Regards,
Neelima Dahi.

Sangra

 Profile Answers by Sangra Questions by Sangra

• Feb 22nd, 2010

 

In case of one Disk failure the mirrored disk would provide the fallback protection
In case of AMP failure the second AMP (in the fallback Clique) can provide the protection
In case of Node failure the alternate node(in the fallback Clique) can provide the access to the data on Disk/ADisk
In case of Clique failure the mirrored/fallback clique can provide the fallback protection.

See the actual data is on the disk and that disk can be accessed through any AMP/Node under Primary or fallback Clique.

There are always two BYNET connecting the above network to support the protection against BYNET failure.

rajnsuccess

 Profile Answers by rajnsuccess 

• Feb 6th, 2011

 

Clique is mainly used to prevent node failures.Group of nodes which share common disk drives is called CLIQUE.

Group of cylindrical or physical disks arranged in array fashion is called VDISKS.

After AMP performing the operations it invokes the controllers to store and manage the data accross physical disks.

Here the two controllers are active and they do the same operation so we call this controllers as DUAL REDUNDANT ACTIVE ARRAY CONTROLLERS.