Sieve is a basic scripting language that can be used for running user devised, server-side filters as a part of a mail system. The ManageSieve protocol however, enables uploading and managing these Sieve scripts on a remote mail server without the need for a direct filesystem access. If you want to use Sieve with your setup, necessarily you have to use the Dovecot LDA instead of the Postfix built in delivery. The Dovecot LDA, which is also called deliver, is a local delivery agent which takes the mail from an MTA and delivers it to a user’s mailbox.
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Security of the system console is more challenging than it appears as there is no precisely secure environment on earth where the physical access is entirely and only granted to you. In reality, all the environmental security measures depend on human factor and declared procedures can be reversed meanwhile you suppose everything is going fine. The conflicts of interests may arise suddenly when especially the attached business value of your data grows. A day arrives and it may turn into a “capture the flag” game between the business partners or any concerned parties.
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