Since I am so new to these forums, I decided to post more information in the hopes that it would help a more skilled Postfix user.
Here is what I have so far in the main.cf:
smtpd_restriction_classes = allowed_only, everyone_access, send_only,
mgmt_access
allowed_only = check_recipient_access hash:/etc/postfix/allowed_domains, reject
everyone_access = check_recipient_access
hash:/etc/postfix/everyone_access, reject
send_only = check_recipient_access hash:/etc/postfix/send_only, reject
mgmt_access = check_recipient_access hash:/etc/postfix/mgmt_access, reject
smtpd_recipient_restrictions = check_sender_access
hash:/etc/postfix/restricted_senders check_recipient_access
hash:/etc/postfix/restricted_recipients permit_sasl_authenticated
reject_unauth_destination
restricted_senders FILE CONTENTS:
acct1@mydomain.com allowed_only
acct2@mydomain.com allowed_only
acct3@mydomain.com allowed_only
acct4@mydomain.com allowed_only
restricted_recipients FILE CONTENTS:
acct10@mydomain.com send_only
acct11@mydomain.com everyone_access
acct12@mydomain.com mgmt_access
acct13@mydomain.com send_only
acct14@mydomain.com mgmt_team
allowed_domains FILE CONTENTS:
mydomain.com OK
everyone_access FILE CONTENTS:
acct20@mydomain.com OK
acct21@mydomain.com OK
send_only FILE CONTENTS:
<blank
Nothing in the File>
mgmt_access FILE CONTENTS:
acct30@mydomain.com OK
OUTPUT from postconf -n COMMAND:
biff = no
command_directory = /usr/sbin
config_directory = /etc/postfix
content_filter = smtp-amavis:[127.0.0.1]:10024
daemon_directory = /usr/libexec/postfix
debug_peer_level = 2
enable_server_options = yes
header_checks = pcre:/etc/postfix/custom_header_checks
html_directory = /usr/share/doc/postfix/html
inet_interfaces = all
local_recipient_maps =
mail_owner = _postfix
mailbox_size_limit = 0
mailbox_transport = dovecot
mailq_path = /usr/bin/mailq
manpage_directory = /usr/share/man
maps_rbl_domains =
message_size_limit = 0
mydestination = $myhostname, localhost.$mydomain, localhost, $mydomain
mydomain = mydomain.com
mydomain_fallback = localhost
myhostname = mail.mydomain.com
mynetworks = 127.0.0.0/8,127.0.0.1/32,10.1.2.241
newaliases_path = /usr/bin/newaliases
queue_directory = /private/var/spool/postfix
readme_directory = /usr/share/doc/postfix
recipient_delimiter = +
relayhost = msg.mydomain.com
sample_directory = /usr/share/doc/postfix/examples
sendmail_path = /usr/sbin/sendmail
setgid_group = _postdrop
smtp_sasl_auth_enable = yes
smtp_sasl_password_maps = hash:/etc/postfix/sasl/passwd
smtpd_client_restrictions = permit_sasl_authenticated reject_rbl_client zen.spamhaus.org permit
smtpd_enforce_tls = no
smtpd_helo_required = yes
smtpd_helo_restrictions = permit_sasl_authenticated reject_invalid_helo_hostname reject_non_fqdn_helo_hostname
smtpd_pw_server_security_options = cram-md5,gssapi
smtpd_recipient_restrictions = check_sender_access hash:/etc/postfix/restricted_senders check_recipient_access hash:/etc/postfix/restricted_recipients permit_sasl_authenticated reject_unauth_destination
smtpd_restriction_classes = allowed_only, everyone_access, send_only, mgmt_access
smtpd_sasl_auth_enable = yes
smtpd_tls_CAfile = /etc/certificates/mail.mydomain.com.A2124A801965D56ECA8EFA8240C82E7D9F4D73F0.chain.pem
smtpd_tls_cert_file = /etc/certificates/mail.mydomain.com.A2124A801965D56ECA8EFA8240C82E7D9F4D73F0.cert.pem
smtpd_tls_exclude_ciphers = SSLv2, aNULL, ADH, eNULL
smtpd_tls_key_file = /etc/certificates/mail.mydomain.com.A2124A801965D56ECA8EFA8240C82E7D9F4D73F0.key.pem
smtpd_use_pw_server = yes
smtpd_use_tls = yes
tls_random_source = dev:/dev/urandom
unknown_local_recipient_reject_code = 550
virtual_alias_maps =
I hope this helps.