The extended datastore must have enough space to contain the amount of data generated by the Discover appliance. The following procedure explains how you can calculate approximately how much free space you need for your extended datastore.
Before you beginFamiliarize yourself with ExtraHop datastore concepts.
- Log into the Web UI of your Discover appliance.
- Click the System Settings icon, and then click System Health.
- Scroll down to the Datastore section.
In the Store Lookback chart, note the Rate and
Estimated Lookback for each metric cycle (or time period) that
you want to store on the external datastore. The rate for 5-minute metrics in
our example figure below is 27.85 KB/s.
Calculate the amount of required space by applying the following formula:
<rate> x <lookback_time>, and then convert the value
to standard units.
To store all of the 5 minute metrics from this appliance for 30 days, you need 1 TB of free space.
- Convert the rate from seconds to days: 27.85 * 60 (minutes) * 24 (hours) * 30 (days) = 1203120 KB for 30 days of lookback.
- Convert the rate from kilobytes to gigabytes: 1203120 / 1024 = 1175 GB for 30 days of lookback.
- Convert the rate from gigabytes to terabytes:1175 / 1024 = 1 TB for 30 days of lookback.
Next stepsConfigure an extended CIFS or NFS datastore.