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User can maintain server's access using that sever Server Security Group.
Security Group List
Security Group List view includes all Server Security Groups and Project Default Security Group.
Project Admin can add another Security Group using 
button.
Default Security Group
Default Security Group is enabled by default to all project servers and includes a few Security Rules which enables access from Servers to external networks and opens ssh connection to Servers.
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User can't create any new Security Rule in Default Security Group.
Server Security Group
Server Security Group includes Security Rules for a selected server.
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User can add a new Security Rule into Server Security Group using button ADD.
Add Security Rule
User can add a new Security Rule in that view or modify existing Security Rules.
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