The E-Mail plugin opens a UNIX domain socket and starts accepting connections on that socket. Clients can connect to this socket and submit statistics about email messages. A sample plugin for SpamAssassin can be found in
Use of this plugin is deprecated. If you want to submit statistics to the daemon, for example about email messages, please use the UnixSock plugin instead.
<Plugin email> SocketFile "/var/run/collectd-email" SocketGroup "mail" SocketPerms 660 MaxConns 4 </Plugin>
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