Hi,
I have a situation in one of my customers. Case 240503-407 .
Here is the situation :
the customer start with a 3 nodes HSX cluster with 24x16TB disk
He adds a fourth node, and because of a shortage of 16TB disk availability he goes with 20TB disk (also with 768GB of ram)
Now if we look at the disks on an 16TB node we see :
/dev/sdn 17T 13T 3.7T 78% /hedvig/d15
/dev/sdc 17T 14T 3.4T 80% /hedvig/d4
/dev/sde 17T 13T 3.7T 78% /hedvig/d6
/dev/sdw 17T 13T 3.7T 78% /hedvig/d24
/dev/sdd 17T 13T 3.8T 78% /hedvig/d5
and if we look at the disks on a 20TB node we see :
/dev/sdt 19T 14T 4.3T 77% /hedvig/d22
/dev/sdx 19T 14T 4.5T 76% /hedvig/d26
/dev/sde 19T 14T 4.4T 77% /hedvig/d7
/dev/sdf 19T 14T 4.3T 77% /hedvig/d8
/dev/sds 19T 15T 4.0T 79% /hedvig/d21
The support said :
- The disk here already seems to be utilizing the 20 TB that is assigned.
- When checked internally, for hyperscale X, the check on the code side would be " equal to or higher ". This means that 20TB could be utilized fully here, which is seen in the disks as well.
- The CAP of 16TB was for hyperscale 1.5, and since we are on hyperscale X here, you can continue to add nodes with 20TB here.
Does it mean they were formated with all the extra space but the Storage Pool won’t use it ?
Also what is happening if we add more nodes in this cluster with 20TB disks ?
The space will never be used ?
If we end up with only 20TB disks in all the nodes, the cluster will only use 16TB of disk space ?
Is there a procedure somewhere on how to replace a node inside a cluster ?
Or we just pull the power of the node we want to replace and reimage a new node in this cluster ?
Answer from support ticket 240503-407 :
As much as I want it to be shared with you, there is no documentation available for the replacement of a node.
Only documentation would be to replace a disk here.
You could raise the concern with the accounts team which could help you in a similar scenario.
From the support perspective, I assure that there are no such documentation/ step that is available.
Those it means, when you start a cluster with a specifique disk size, the only way to change it is to start a brand new cluster ?
