Bonjour,
Je viens de configurer un serveur postfix, et j'arrive à envoyer des mails vers l'éxtérieur (gmail.com,orange.fr,yahoo.com..), mais seulement en local.
Dés que j'essaye d'envoyer un mail avec un client de messagerie extérieur au réseau local du serveur, le serveur retourne "Relay access denied".
D'autre part, le serveur n'arrive pas à recevoir de courrier venant de l'extérieur.

Pourriez-vous m'aider ?

Merci d'avance

Voici la conf de Postfix :

# See /usr/share/postfix/main.cf.dist for a commented, more complete version


# Debian specific:  Specifying a file name will cause the first
# line of that file to be used as the name.  The Debian default
# is /etc/mailname.
#myorigin = /etc/mailname

smtpd_banner = $myhostname ESMTP $mail_name (Debian/GNU)
biff = no

# appending .domain is the MUA's job.
append_dot_mydomain = no

# Uncomment the next line to generate "delayed mail" warnings
#delay_warning_time = 4h

readme_directory = no

# TLS parameters
smtpd_tls_cert_file=/etc/ssl/certs/ssl-cert-snakeoil.pem
smtpd_tls_key_file=/etc/ssl/private/ssl-cert-snakeoil.key
smtpd_use_tls=yes
smtpd_tls_session_cache_database = btree:${data_directory}/smtpd_scache
smtp_tls_session_cache_database = btree:${data_directory}/smtp_scache

# See /usr/share/doc/postfix/TLS_README.gz in the postfix-doc package for
# information on enabling SSL in the smtp client.

myhostname = l-p-system.com
alias_maps = hash:/etc/aliases
alias_database = hash:/etc/aliases
myorigin = /etc/mailname
mydestination = l-p-system.com, sd-66632.dedibox.fr, localhost.dedibox.fr, localhost, smtp.l-p-system.com
relayhost = 
mailbox_command = procmail -a "$EXTENSION"
mailbox_size_limit = 0
recipient_delimiter = +
inet_interfaces = all

home_mailbox = mail/
inet_protocols = all