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SSD Total Bytes Written (TBW) Calculator

Solid-State-Drives are getting more and more common. A problem that comes with SSDs is their limited cell lifetime. Depending on their manufacturing technique, each cell can be overwritten from 1.000 times in consumer TLC SSDs to up to 100.000 times in enterprise SLC based SSDs.

The value to keep an eye on is the guaranteed TBW (Total Bytes Written or Terabytes Written) which is typically provided by the vendor in their specifications. This value describes how many Terabytes can be written to the device until the warranty expires. The TBW value can be readout with S.M.A.R.T. in the Total_LBAs_Written field. The value is in LBAs which has to be multiplied with the sector size:Read More »SSD Total Bytes Written (TBW) Calculator

VMware VSAN License Calculator

VMware Virtual SAN and its pricing model is now available. The pricing model is very simple and, just like the model for the hypervisor, based on CPU sockets. There is no feature, capacity or scale limit. VSAN has to be licensed on top of the hypervisor and the whole cluster has to be licensed. This implies that you have to license each host in the cluster, even when it does not have any local disks and is only part of the cluster as a VSAN Agent. A more detailed description of VSAN licensing is available here.

I've created a VSAN License Calculator. Just enter the number of hosts and sockets per host in your cluster and it will calculate the total price of all required VMware products. It also includes a license cost breakdown which shows the price for each component separately.


Read More »VMware VSAN License Calculator