ISPConfig3 Quota System for Email Accounts

[atjensen11]

How are quotas managed for email accounts in ISPConfig3?

My question stems from trying to configure my new installation of Squirrelmail on this server as the old production machine. On that machine, I had installed Squirrelmail with the check_quota plugin. The old production machine did not use ISPConfig.

Within the check_quota plugin, you are able to configure quota display only if the quota system is UNIX filesystem quotas, IMAP quotas, or cPanel quotas. Obviously, ISPConfig would not use cPanel quotas.

But I have tried the other two settings and the quota bar graph will not display. I wanted to confirm that email accounts with quotas are one of the three types so I can troubleshoot correctly.

Lastly, is my intent to display quota information within Squirrelmail redundant? Does ISPConfig3 notify or otherwise show users information regarding their current usage?