The fictional Siroe Corporation has two Messaging Multiplexors on separate machines, each supporting several Messaging Servers. POP and IMAP user mailboxes are split across the Messaging Server machines, with each server dedicated exclusively to POP or exclusively to IMAP (You can restrict client access to POP services alone by removing the ImapProxyAService entry from the ServiceList setting; likewise, you can restrict client access to IMAP services alone by removing the PopProxyAService entry from the ServiceList setting.). Each Messaging Multiplexor also supports only POP or only IMAP. The LDAP directory service is on a separate, dedicated machine.
This topology is illustrated below in Figure 7–2.
The IMAP Messaging Multiplexor in Figure 7–2 is installed on sandpit, a machine with two processors. This Messaging Multiplexor is listening to the standard port for IMAP connections (143). Messaging Multiplexor communicates with the LDAP server on the host phonebook for user mailbox information, and it routes the connection to the appropriate IMAP server. It overrides the IMAP capability string, provides a virtual domain file, and supports SSL communications.
This is its ImapProxyAService.cfg configuration file:
default:LdapUrl ldap://phonebook.siroe.com/o=internet default:LogDir /opt/SUNWmsgsr/config/log default:LogLevel 5 default:BindDN "cn=Directory Manager" default:BindPass secret default:BacksidePort 143 default:Timeout 1800 default:Capability "IMAP4 IMAP4rev1 ACL QUOTA LITERAL+ NAMESPACE UIDPLUS CHILDREN BINARY LANGUAGE XSENDER X-NETSCAPE XSERVERINFO" default:SearchFormat (uid=%s) default:SSLEnable yes default:SSLPorts 993 default:SSLSecmodFile /opt/SUNWmsgsr/config/secmod.db default:SSLCertFile /opt/SUNWmsgsr/config/cert8.db default:SSLKeyFile /opt/SUNWmsgsr/config/key3.db default:SSLKeyPasswdFile /opt/SUNWmsgsr/config/sslpassword.conf default:SSLCipherSpecs all default:SSLCertNicknames Siroe.com Server-Cert default:SSLCacheDir /opt/SUNWmsgsr/config default:SSLBacksidePort 993 default:VirtualDomainFile /opt/SUNWmsgsr/config/vdmap.cfg default:VirtualDomainDelim @ default:ServerDownAlert "your IMAP server appears to be temporarily out of service" default:MailHostAttrs mailHost default:PreAuth no default:CRAMs no default:AuthCacheSize 10000 default:AuthCacheTTL 900 default:AuthService no default:AuthServiceTTL 0 default:BGMax 10000 default:BGPenalty 2 default:BGMaxBadness 60 default:BGDecay 900 default:BGLinear no default:BGExcluded /opt/SUNWmsgsr/config/bgexcl.cfg default:ConnLimits 0.0.0.0|0.0.0.0:20 default:LdapCacheSize 10000 default:LdapCacheTTL 900 default:HostedDomains yes default:DefaultDomain Siroe.com |
The POP Messaging Multiplexor example in 7.4.1 A Sample Topology is installed on tarpit, a machine with four processors. This Messaging Multiplexor is listening to the standard port for POP connections (110). Messaging Multiplexor communicates with the LDAP server on the host phonebook for user mailbox information, and it routes the connection to the appropriate POP server.
This is its PopProxyAService.cfg configuration file:
default:LdapUrl ldap://phonebook.siroe.com/o=internet default:LogDir /opt/SUNWmsgsr/config/log default:LogLevel 5 default:BindDN "cn=Directory Manager" default:BindPass password default:BacksidePort 110 default:Timeout 1800 default:SearchFormat (uid=%s) default:SSLEnable no default:VirtualDomainFile /opt/SUNWmsgsr/config/vdmap.cfg default:VirtualDomainDelim @ default:MailHostAttrs mailHost default:PreAuth no default:CRAMs no default:AuthCacheSize 10000 default:AuthCacheTTL 900 default:AuthService no default:AuthServiceTTL 0 default:BGMax 10000 default:BGPenalty 2 default:BGMaxBadness 60 default:BGDecay 900 default:BGLinear no default:BGExcluded /opt/SUNWmsgsr/config/bgexcl.cfg default:ConnLimits 0.0.0.0|0.0.0.0:20 default:LdapCacheSize 10000 default:LdapCacheTTL 900 default:HostedDomains yes default:DefaultDomain Siroe.com |