For plesk version 10 and above
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1. Log into plesk control panel.
2. Select the desired domain from "Domains" list.
3. Select statistics tab.
4. This page shows the disk space and bandwidth usage.
For plesk version 9
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1. Log into plesk control panel.
2. Select the desired domain from "Domains" list.
3. Select "Statistics" tab.
4. This field includes web statistics, Resource usage, Traffic usage and Log Manager.