ldapsearch -x -D "uid=search-user,ou=People,dc=example,dc=com" \
           -W -H ldap://ldap.example.com -b "ou=People,dc=example,dc=com" \
           -s sub 'uid=test-user'

was not aware this, but already on Fedora

 

https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/7/html/System-Level_Authentication_Guide/Configuring_Services.html

sudo postconf -e defer_transports=smtp;sudo postfix reload : pause email delivery but still accept email.
postcat -qv 2E4C42104D
sudo postconf -e defer_transports=;sudo postfix reload;sudo postfix flush : unpause mail delivery… resume email delivery after it has been paused

postsuper -d ALL


postsuper -d [msgid] : delete one email with id [msgid]; previously obtained with a command such as mailq|grep -i [string] or mailq|more

postfix reload : after any changes to the configuration the server has to be reloaded to read the new configuration

postfix -f : flush the mail queue… to help postfix resume delivery faster after it has been paused such as after the computer reconnected

To make it auto-set this value on boot uncomment this line in/etc/sysctl.conf

#net.ipv4.ip_forward=1

Then set up some rules in iptables to perform the natting and forwarding:

# Always accept loopback traffic
iptables -A INPUT -i lo -j ACCEPT

# We allow traffic from the LAN side
iptables -A INPUT -i eth0 -j ACCEPT

######################################################################
#
#                         ROUTING
#
######################################################################

# eth0 is LAN
# eth1 is WAN

# Allow established connections
iptables -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT
# Masquerade.
iptables -t nat -A POSTROUTING -o eth1 -j MASQUERADE
# fowarding
iptables -A FORWARD -i eth1 -o eth0 -m state --state RELATED,ESTABLISHED -j ACCEPT
# Allow outgoing connections from the LAN side.
iptables -A FORWARD -i eth0 -o eth1 -j ACCEPT