You have just completed a default Oracle Solaris 11 installation of a new server system. While
testing network connectivity from your desktop to the server, you find that you are not able to
communicate with the “sendmail” service from your desktop. Why is this?
A.
By default, the “sendmail” software is not installed.
B.
By default, “sendmail” is not enabled on the system.
C.
By default, “sendmail” access is blocked by TCP Wrappers.
D.
By default, “sendmail” responds to local requests only.
E.
By default, “sendmail” is running on its encrypted port.
Explanation:
Note:
*sendmail
*Enabling Access to Remote Clients
On an unmodified system, access to sendmail by remote clients is enabled and disabled through
the service management facility (see smf(5)). In particular, remote access is determined by the
value of the local_only SMF property:
svc:/network/smtp:sendmail/config/local_only = true
A setting of true, as above, disallows remote access; false allows remote access. The default
value is true.
The following example shows the sequence of SMF commands used to enable sendmail to allow
access to remote systems:
# svccfg -s svc:/network/smtp:sendmail setprop config/local_only = false# svcadm refresh svc:/network/smtp:sendmail
# svcadm restart svc:/network/smtp:sendmail
Reference:man pages section 1M: System Administration Commands, sendmail
D is correct:
By default, the sendmail daemon runs in the new local daemon mode. The local–only mode only accepts incoming mail from the local host or loopback SMTP connections. For instance, mail from a cron job or between local users would be accepted. Outbound mail is routed as expected, only the incoming mail is changed. The -bl option is used to select the local-only mode, also known as the Become Local mode. For more information about this mode, see the sendmail(1M) man page. For instructions on how to change back to the -bd or Become Daemon mode, see How to Use sendmail in the Open Mode.
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