proxyd - Cyrus IMAP documentation

       The Cyrus Team

       1993–2025, The Cyrus Team

3.10.2                                            Jun 27, 2025                                         PROXYD(8)

imapd  is  an  IMAP4rev1  server.  It accepts commands on its standard input and responds on its standard
       output.  It MUST be invoked by master(8) with those descriptors attached to a remote client connection.

       imapd reads its configuration options out of the imapd.conf(5) file unless specified otherwise by -C.

       If the file msg/shutdown is created under the directory specified in  the  configdirectory  configuration
       option,  then  imapd  will  shut down the connection, sending the first line contained in the file to the
       client as the reason.  New connections are denied.

       If the file msg/motd is created under  the  directory  specified  in  the  configdirectory  configuration
       option,  then  imapd  will  send the first line contained in the file to clients upon connect as an ALERT
       message which IMAP-compliant clients are required to display.

       This option serves to annoy users mostly.  Unfortunately clients tend to connect far more frequently than
       is apparent, generating a separate server ALERT for each connection.  Many clients do not  display  these
       properly, if they do anything with them at all.

       If  the  directory  log/user  exists  under  the directory specified in the configdirectory configuration
       option, then imapd will create protocol telemetry logs for sessions authenticating as user.

       The telemetry logs will be stored in the log/user directory with a filename of the imapd process-id.

imapd is commonly included in the SERVICES section of cyrus.conf(5) like so:

          SERVICES {
              imapcmd="imapd-U30"listen="imap"prefork=0imapscmd="imapd-s-U30"listen="imaps"prefork=0maxchild=100
              lmtpunix    cmd="lmtpd" listen="/var/run/cyrus/socket/lmtp" prefork=0 maxchild=20
              sieve       cmd="timsieved" listen="sieve" prefork=0
              notify      cmd="notifyd" listen="/var/run/cyrus/socket/notify" proto="udp" prefork=1
              httpd       cmd="httpd" listen=8080 prefork=1 maxchild=20
          }

       /etc/imapd.conf

       proxyd - Cyrus IMAP documentation

       Proxyd is a symlink to imapd(8) if you build with murder enabled.

-Cconfig-file
              Use the specified configuration file config-file rather than the default imapd.conf(5).

       -Uuses
              The maximum number of times that the process should be used for new  connections  before  shutting
              down.  The default is 250.

       -Ttimeout
              The  number of seconds that the process will wait for a new connection before shutting down.  Note
              that a value of 0 (zero) will disable the timeout.  The default is 60.

       -D     Run external debugger specified in debug_command.

       -s     Serve IMAP over SSL (imaps).  All data to and from imapd is encrypted  using  the  Secure  Sockets
              Layer.

       -N     Bypass password checking.  (Not recommended unless you know what you're doing.)

       -pssf Tell  imapd  that  an  external  layer  exists.   An  SSF (security strength factor) of 1 means an
              integrity protection layer exists.  Any higher SSF implies some form of privacy protection.

imapd.conf(5), master(8)

imapd [ -Cconfig-file ] [ -Uuses ] [ -Ttimeout ] [ -D ]
              [ -s ] [ -N ] [ -pssf ]